Subject: Re: Rocket Fuels
From: [email-masked] (Joan Barlow)
Date: 8 Oct 95 00:20:35 GMT

Could some one send me an e-mail on how to make up a
Nitrate/Sugar/sulfur propellant eg. quantities, procedures, equipment.

Article: 19718 of rec.models.rockets
From: [email-masked] (William )
Subject: Rocket cameras...
Date: 02 Oct 1995 06:20:40 GMT
Lines: 67
Message-ID: <[email-masked]>

A while ago, while people were talking about HPR launchable cameras,
and I made an offhand comment to the effect that disposable cameras
were shrinking.  Someone asked whether they fit in the 2.6 inch body
tubes (used by the larger aerotech models)...

Well, today I gave in to temptation and bought a Kodak "NEW" "FunSaver
Pocket camera"  (about $9) to check things out in mode detail...

First the good news:

	It JUST fits in an aerotech 2.6inch body tube (eg the payload
	section of an Astrobee.)

	I think it ways less than 4 ounces (can't seem to find my scale
	at the moment.)

Now the less good news:

	"JUST fits" means that quite a bit of creativity might be needed
	to build a mechanism to push the shutter button.  The button is
	right at the part that comes closest to the body tube.

	I haven't taken it apart yet to evaluate whether modifications
	are feasible.

	I had envisioned a hack where half the shutter window would be
	masked off (doubling the shutter speed), and the camera reloaded
	with faster film to compensate (ie 400 ASA instead of 200.)
	Unfortunately, this camera already uses 400ASA film, so you'd
	have to go to 1000ASA film to keep things synced.  1000ASA film
	is rather expensive and not nearly as widely available.

And the "discussion":

	A "Focal" (K-Mart brand?) camera seemed to be similar in size
	and cheaper, but I didn't see one without a flash.  Focal is
	to be commended because they listed the lense focal length (34mm)
	and shutter speed (1/125 s) on the back of the box.  This camera
	also contained ASA400 film, so the numbers are probably similar
	for the kodak.  (For the hacker award, use the cameras flash system
	to fire the ejection charge wile simultaneously taking a photo!)

	For those of you who AREN'T aware of the way these work, the
	camera starts with bare 35mm film in one half, and uses a
	standard film cartridge for the take-up reel.  (well, previous
	versions did.  I think it's pretty much a requirement that this
	be done in order for all the 1hour photo places to be able to
	deal with the exposed film.)  So you can get one of these
	cameras, use up all the film taking pictures of your wife's
	sister's wedding, and then take it apart, get the film processed
	normally while keeping the casing to experiment with.  (also,
	a friendly photo store can probably give you as many used cases
	to experiment with as you could want.  While the cases are apparently
	recycled, kodak/etc doesn't seem to pay the photo stores very
	much to do so...)  You will need a dark room of some kind, and
	probably a fair degree of manual dexterity, to reload the camera
	with fresh film...

	Load more than one camera in the same payload section to take
	sequences of photos.  My "mechanical aptitude" isn't too good;
	I'd be grateful for any ideas leading to timing devices capable
	of "pushing the buttons"...

BillW

Article: 19719 of rec.models.rockets
From: [email-masked] (William )
Subject: Cheap klingon battle cruisers...
Date: 02 Oct 1995 06:27:40 GMT
Lines: 15
Message-ID: <[email-masked]>

The local "toys R us" seems to be closing out the (discontinued) Estes
Klingon Battle cruiser (one of the few SF ships that's almost stable!)
The kit WITH paints (2 spray cans, 4 bottles) was going for about $10.
I was nice and only picked up one of them...  The paint alone is worth
(well, "would cost") that much...

They also had a neat air-powered rocket for smaller kids (constructed along
lines similar to the NERF weapons, but modified to require pointing it
straight up.)  $5.  My almost-two year old thinks it's great, and can almost
operate it by herself.  Sends a little foam rocket rather impressively high.
The "thrust tube" is SLIGHTLY too big to fit in a BT20.  Rats.

BillW

Article: 19720 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: launch report for central IL, 9/23/95
Date: 03 Oct 1995 04:35:47 GMT
Lines: 12
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
	<[email-masked]>
	<[email-masked]>

    [Anti-gopher smoke devices]

    Unless you plan on flying them in competition (scale?) it shouldn't be
    necessary. I've "flown" them at the past 3 NARAMS on the sport range. CMASS
    runs them, and they run S&T as well. No one has ever been concerned about
    them. They aren't rocket motors, thus shouldn't need certification.

Well, being certified as a zero-thrust model rocket motor might come in
handy where "fireworks" like smoke bombs are normally illegal.  (Although
I'm pretty sure MASS is amoung such states...)

BillW

Article: 19721 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Super Vega Body Tube...
Date: 03 Oct 1995 04:50:59 GMT
Lines: 25
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

    >I'm just about finished with an overbuilt Super Vega that I plan on
    >flying with Aerotech reloads.  I've strengthened pretty much
    >everything on the bird except for the body tube itself.  So I was
    >wondering if I should also strengthen the body tube in order for it to
    >be able to stand up to the ejection charges of the AT reloads???  It's
    >a good-sized tube (I think it's a BT60 over 18" long).....

    It's probably simpler to just assemble the reload with only a portion of 
    the powder provided -- ask someone with experience using reloads how 
    much you're likely to need for that airframe, but many smaller rockets 
    seem to work well on 1/3 to 1/2 of the supplied powder.

Someone (ntaib?) has commented in the past that they've flown Big Berthas on
Aerotech motors through various large sizes (up to a 29mm G, I think.)  the
big bertha has an 18" BT-60 (and yes, the super-vega is BT-60.)

If you want, I bought some of the "Beefy-60" tubes jsvrc was selling 18
months ago, and I'd be happy to bring one to the next lunar launch and sell
it to you at cost ($1.50 for a 36" tube...)  I wasn't planning on using it
for MY beefed-up super-vega.  (then again, the way Victoria finishes rockets,
maybe I'll save my super vega for after one of us moves. .. Just kidding.
Maybe we can drag-race them.)

BillW

Article: 19722 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Could someone help with my Phoenix c.p. question ???
Date: 05 Oct 1995 06:21:28 GMT
Lines: 21
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
	<[email-masked]> <[email-masked]>

Can the "cardboard cutout" technique be generalized by having the rocket
"cast its shadow" at multiple angles of attack, and ensuring that the cg
of the projection (~Cp)is always behind of the cg of the actual model?

Ought to be something a computer would be good at!

It would be rather nice, cause I think it generalizes even further into
asymetric fin configurations and such by rotating the model around all
axis of non-symetry, right?

You would have to have a mathematical model of what your rocket looked
like, but after that standard computer graphics algorithms for projecting
3d objects onto 2d planes would handle most of the work.

The info input into the current Barrowman programs ought to be sufficient
to build the internal model.

I don't know if it would handle tube-finned rockets (significant airflow
in "hidden" areas), or surfaces that actually generate lift, however.

BillW

Article: 19723 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Launch Report -- 9/23/95
Date: 05 Oct 1995 07:58:23 GMT
Lines: 44
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
	<[email-masked]>

    > But it's always nice to meet someone who can make them
    >look like they do in the catalogs...

    That always took me by surprise.  I would hand you models thinking
    "please don't look too closely at the way that it looks" and the first
    thing you'd say was "beautiful."

Well, I don't know how highly you should value my opinion - I always admire
things I don't do well myself.  Paint doesn't like me very much, and decals
REALLY have it in for me.  As a result, I don't take painting very
seriously.  Rockets are likely to be flown at least once before painting
them at all, and then the finishing process becomes an experiment more than
an improvement.  Then I leave the nosecones white so I can move them between
models if I want.  I have a nice Stealth fighter done in Automotive paint
(which is very thick and heavy, and covers very well indeed.)  "trim" was
done with a black magic marker! However, the paint and decals BOTH crinkled
quite badly in spots when I added clear a overcoat on top of the decals.
Then I put something heavy on top of it, cracking fins, which got CA wicked
in for a fix.  Sigh.  Then I have this nice Nova Payloader, on which I used
several different filling techniques, including arcrylic "gesso" (works
well, but somewhat heavy.)  It has a wonderful transparent red over metalic
silver paint-job that worked really well.  Only the decals wrinkled on this
one...  My gyroc has fins in hand-painted (with a brush, or was it a q-tip?)
4-color fluorescent paints.  I like the Rotaroc-A - It's instructions said
not to paint it at all.  The Arreaux-clone has floral paint on its payload
section, with a wipe-on gloss polyurethane overcoat (too thin, in general.)
The bottom had several coats of actual "primer", alternating colors so I
could check coverage and sanding.  I only took a little piece of paint off
the payload section trying to buff up the finish.  Magic markers (of various
kinds) worked pretty nicely on the little vellum rocket (now retired.)  My
attempt at mono-coating didn't go well at all, and I didn't like the
expensive matching-color "epoxy" spray paint that I used with it either (too
transparent, and it wasn't supposed to be!)

I've got kid paints, fabric paints, auto paints, cheap paints, expensive
paints, glass paints, floral paints, glitter paints, 3D paints, big cans,
little cans, bottles of every shape and size.  I've gathered technology
from half-a-dozen differnt crafts, and I play with it, and I have fun,
and my rockets look OK, even nice, as long as you don't get too close.

But I don't have ANY that look like the catalog photos :-(

BillW,  Lunar #256 - Another easy number to remember.

Article: 19724 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Wiring an Adept Altimeter on a PML
Date: 07 Oct 1995 00:50:23 GMT
Lines: 29
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Speaking of ejections charges, can you put the ejection charge of a
moderately sized rocket AHEAD of the parachute?  (requiring the separatation
to drag it out by the shock cord.)  That stage coupler (3" by 6" in a 3"
rocket) is an awfully tempting spot to mount electronics and ejection
charges.

	 PAY
	 LOAD                            PAY
        [_____]   	How about:       LOAD
        [| A |]   		        [_____] 
        [| A |]   		        [|A E|]   A == Altimiter
        [| A |]   		        [|A E|]   E == Ejection charge
         |   | Coupler 		        [|A E|]  	(in tube) 
         |E  |    		         |--E|    Coupler
         |E  |    		         |CCC|  
        [ E   ]   		         |CCC|    C == Chute
        [     ]   		        [     ] 
        [     ]   		        [     ] 
        [ CCC ]   		        [     ] 
        [ CCC ]   		        [     ] 
        [     ]   		        [     ] 
                  		        [     ] 

In both case, I'm worried about the ejection charge blowing the chute
deep down into the body tube where it won't get pulled out.

Thanks
Bill W

Article: 19725 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: plans
Date: 07 Oct 1995 00:53:35 GMT
Lines: 8
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

    Then there are the very rare Czech "Delta" motors that are about 5 x 20mm
    and labeled in meters for "indoor" rocketry.

Gee, with all the stuff being exported from the Czechs these days (model
airplanes, mostly?) I wonder if there's a chance of getting these added
to the list?

BillW

Article: 19726 of rec.models.rockets
From: [email-masked] (William )
Subject: More Cheap tricks: Paint and decals
Date: 07 Oct 1995 08:01:31 GMT
Lines: 24
Message-ID: <[email-masked]>

Most "home improvement" type stores that do paint color matching will have
batched of various types of paint that didn't come out quite right on sale
for very low prices.  The other day at Orchard, there were quarts of assorted
paints (both water and non-water based enamels, latex, etc) for $1, and
gallons for $4.  Colors may not be what you had in mind, but there are
almost always assorted shades of "almost white" that are likely to work
quite well as primer coats...

Using laser-printable self adhesive "Repro film" to make your own decals has
been mentioned before, but the material can be difficult to find in small
quantities, or at least so I suspected.  A recent trip to the local Kinko's
("Your Branch Office", a copy place) turn up that they have this stuff, and
will sell it to you, or copy onto it for you.  Once sheet at a time if you
want.  They gave me two sheets (for the price of one) at $.75 to take home
to "experiment with" (I guess cause I didn't have them copy onto it.)  But
this was late at night, and the actual price might be higher.  (Their price
guide lists "transparent label - full sheet" at $1.25)  This is comparable
to the per-sheet price someone quoted for "serious graphics arts stores",
which are harder to find, and won't copy to it for you.  I probably should
have asked if they could make color copies onto it, but I forgot.

Enjoy
BillW

Article: 19727 of rec.models.rockets
From: [email-masked] (Craig Utley)
Subject: Re: Kid groups for Rocktrey
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
Date: Sun, 8 Oct 1995 03:17:30 GMT
Lines: 20

JABeecher ([email-masked]) wrote:
: Hi, I'm a substitute teacher in ISD #283 in the Twin Cities metropolitan
: area.  A lot of the kids I work with have interest in building and
: launching rockets, but I have no idea who to refer them to.  Are there any
: groups which do parent/child launchings in my area?  Parents ask all the
: time, and although I could invite them to my own launches, there are so
: many I hesitate.  I guess I will if there are no organizations in the
: area...the hobby must go on! 

Start a group.  Estes sells a book on getting a club up and running, as 
welll as books on how to make rocketry educational.  Quest has some 
similar publications as well.  When I say book, they are really "guides" 
and cost about $5.00 or less.  Talk to both Estes and Quest for starters, 
and you will find both helpful.

--Craig
-- 
+---------------------------+
| Finger for PGP Public Key |
+---------------------------+

Article: 19728 of rec.models.rockets
From: [email-masked] (LarryC)
Subject: Re: Fins for Scratch built?
Date: 8 Oct 1995 00:53:24 -0400
Lines: 13
Message-ID: <[email-masked]>
References: <[email-masked]>

MonkyTrama ([email-masked]) wrote:
> I was wondering if there were any companys that sell fins alone. since i
> have no access to any adequit cutting devices, i would have to buy some,
> or pay some one to cut them. Any information would help a great deal
> Thanx
> Matt

Yeah, well join the club. A *lot* of us in this group aren't allowed to
handle anything sharp 3-)

Regards,
-Larry (writing this in crayon) Curcio

Article: 19729 of rec.models.rockets
From: [email-masked] (Bill Nelson)
Subject: Re: Super Vega Body Tube...
Date: 7 Oct 1995 06:54:26 GMT
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

[email-masked] wrote:
: In article <[email-masked]>, [email-masked] (Bill Nelson) writes:
: > 
: > One nice thing about reloads is that you can easily tailor the ejection
: > charge to go with the rocket. There is no law that says  you have to use
: > all the powder.  For that matter, if you save up the excess, you will 
: > have some available for the occasional rocket that needs more than was
: > supplied with the reload.

: I keep a 35mm film can in my reload box for storing the excess. You don't
: want a metal container that could accidentally ignite anything when
: opening/closing...

A metal screwtop film can is probably not a hazard - especially with the
rubber seal they have at the top. After all, black powder is sold in one
pound metal cans.

Bill

Article: 19730 of rec.models.rockets
From: [email-masked] (Bill Nelson)
Subject: Re: Homemade Engines
Date: 7 Oct 1995 07:05:02 GMT
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]>

LSchiel ([email-masked]) wrote:
: Ive been launching rockets for 3-4 years and those darn estes engines are
: to expensive.  Anybody know how to make homemade engines?

Yes, a number of us know how.  The problem is, you would spend several
hundred dollars on tooling and materials - and have many failures before
you developed a motor that worked well and consistantly.

Bill

Article: 19731 of rec.models.rockets
From: [email-masked] (Bill Nelson)
Subject: Re: Rocket Fuels
Date: 7 Oct 1995 21:47:24 GMT
Lines: 75
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

x ([email-masked]) wrote:
: In <[email-masked]> [email-masked] (Bill Nelson) writes: 
: >
: >Yep, and there were many young people either maimed or killed while
: >experimenting with them.

: The uninformed should not "experiment" with high energy fuels. Either
: you know what your doing or you don't do it.

Agreed - or you need to be working under the guidance of someone who does.
Most people who want to experiment do not have the luxury of working with
the RRS.

: >They DO explode quite frequently - even the modern firings using heavy
: >duty stainless steel casings.

: Properly designed and built rocket engines by definition, do not
: explode. Mine do not. Yes, I use stainless steel casings, what do you
: use, aluminum?

There are no guarantees. Even the most carefully built motor can fail, due
to a number of reasons. While you (using RRS facilities) are well protected,
most experimenters would not be.

I don't build motors with such high chamber pressures any more - so have
no need for steel casings. The aluminum casings I use are designed to fail
by blowing an end closure - rather than rupturing a casing, if the pressures
get too high. Also, the composite fuels I use are not nearly as sensitive
to spark/flame/friction/impact as the Zn/S fuels. Nor do they burn very well
when not pressurized.

: >I like them too. As you say, there is a lot of flame and smoke -
: mostly
: >due to a fair share of the propellant being blown out of the nozzle
: >before it burns.

: All the smoke is due to the fact that the exaust is composed almost
: entirely of zinc sulfide. There is minimal unburnt propellant ejected.

Hm, this goes counter to all I have read and experienced. Do you use a
binder to keep the fuel one solid mass?

: >The fuel is also fairly static sensitive. 

: As compared to what, Concrete? A 35Kv discharge at .01Ma. ignited AP
: fuel and did not ignite Zn/S fuel. Where do you get these "facts"?

I could start with Brinley, as well as all the other references which
state that the fuel can be ignited by a spark - even one generated by
tooling. 

: >Your experience is NOT typical. The Smoke Creek test site is littered
: >with the remains of such attempts.

: All that tells me is the folks playing with Zn/S motors at Smoke Creek
: should switch to something they are more familiar with. I hear those
: water rockets you pump up are quite safe. Perhaps you guys should stick
: with those.

The point is - the same thing will happen to people who do not have expert
guidance. Without the proper facilities, injuries and deaths will occur,
just like they have in the past.

: >Yes, I made them in the late 50s and early 60s - when it was all the
: >craze. No more. The Isp is poor and the peak pressures much too high.

: I've built Lox/Kerosene, Zn/S, Blackpowder, H2O2 and various hybrid
: motors. All have their advantages and disadvantages. All are potential
: bombs if not designed & built properly. As with anything dangerous, you
: just have to know what your doing or you get burned.

Agreed. However, knowing what you are doing is no guarantee of safety,
although it will greatly improve your odds.

Bill

Article: 19732 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Iron-on covering
Date: 08 Oct 1995 07:00:18 GMT
Lines: 42
Message-ID: <[email-masked]>
References: <[email-masked]>

    Also, filling and painting adds loads of weight and no strength!
    A good iron-on coverling adds significant strength to the
    structure with less weight than paint & fillers.  Paint actually
    weighs more after it dries, because as paint dries, the solvent
    molecules are released into the air and long chains of oxygen
    molecules attach themselves to the paint molecules, making the
    paint dry and insolvent and heavier!

I don't think I believe any of that.  At least for modern paints.  Might
have been true for oil-based paints in days of yore.  And I suspect that
the layers of paint and fillers do add quite a bit of strength to balsa
(though I'll admit that it's not near as much strength as is added by the
iron on coatings.)

    For years I have followed the Estes balsa filler dogma.  My
    question is, why don't people use iron-on covering for fins and
    body tubes of rockets?

Well, I think most people don't follow the balsa filler dogma (see my
recent diatribe about finishing experiments.)  With a cheap can of spray
paint, you can make a model rocket look "ok" very quickly indeed, with far
less trouble than coating a single fin with iron-on coverings.

The fin-body joints are a problem.  The more interesting models have
multiple such joints (ie Solar Warrior, with tubes on the ends of fins.)
The iron-on coverings aren't so good at handling concave surfaces in
general.  The nose cone is a problem as well.  The launch lug is a
problem.  The coverings are more expensive than paint.  Some of the estes
models have embossed carboard or vacuum formed plastic, which shows as
patterns through paint, but won't work with coverings.  The colors
available are "airplane" oriented rather than rocket oriented.  The
coverings are nice for models with a lot of fin/wing and not much body
(like RCBG), but that's the opposite of most rockets.  The coverings are
not available at Walmart.  It's not clear that they'll stay atatched as
well as paint at teh sort of speeds rockets can attain.

That said, I did buy a bunch of such coverings when a local hobby store
went out of business and was selling them at 40% off...  I'm experimenting.

BillW

Article: 19733 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Igniting flashbulbs?
Date: 08 Oct 1995 07:06:15 GMT
Lines: 25
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
	<[email-masked]>

    : Here's a thought... how about a 12 volt lighter battery? weighs almost
    : nothing, will  reliably fire flashbulbs all day long (I have one used on

    Hmmmm..  an idea!  I belive they are a bit pricy, compared to 
    other batteries,  but the weight factor may be nearly the same
    as a big cap.  I'll look into them....

A quad-A 1.5v battery (take apart a 9V alkaline and you'll find six of
these) will fire flashbulbs just fine.  My old flash unit has an (expensive)
15V battery and a couple hundred microfarad capacitor, but battery
technology has come a long way since then (in particular, alkalines and
nicads both can provide much more current in a small package than the old
dry-cells.)  An N sized nicad probably wouldn't have any trouble fireing a
flash-bulb either.

The 12V lighter batteries are quite nice for powering electronics that need
more than 1.5V to run.  Much lighter than any combination of obtainable 4
1.5V cells, and quite a bit cheaper than 6V batteries that are similar in
size.  I mentioned earlier that modern electronics can generate higher
voltages from as little as 1.5V cells anyway, but little in the way of
rocket electronics currently incorporate such boosters, and even the parts
aren't so easy to find.

BillW

Article: 19734 of rec.models.rockets
From: [email-masked] (Jon Pike)
Subject: Re: Igniting flashbulbs?
Date: 8 Oct 1995 07:57:36 GMT
Lines: 15
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

: Also, by the way, the old electrically triggered FLASHCUBES contain acceptable flashbulbs. They
: are harder to find these days. The MAGICUBES out there are mechanically actuated and are
: not suitable.
: - R. Stein

	Ah, yes..  I had the choice of: A. Magicubes  B. the Flip Flash 
at the store I dropped into.  I did realize before buying them that they 
were the mechanical type, so I got the other, only to find their need for 
a HV spark..  :-)   I'm going to a REAL photostore next time, for a better 
selection!

	I do appriciate the great info you all are sharing..

Jon

Article: 19736 of rec.models.rockets
From: [email-masked] (Slc.dennis Bishop)
Subject: IAR Newsletter #1
Date: Sun,  8 Oct 1995 05:44:12 GMT
Message-ID: <[email-masked]>
Lines: 122     

                   Independent  Assoc.  of  Rocketry

                                9509.20 

                                 Vol.1 #1

    Dennis Bishop ... 85-373 Plantation Rd. #5 ... Waianae,Hi.96792

           Voice/Fax  808-696-0817    BBS 808-696-7763  14.4kb

   Welcome to the 1st Newsletter of the IAR. I will try to make it as
good as
I can, but it is still in the building stage, much like the IAR itself.

   I have been watching the world of both model rocketry and high power
rocketry. I myself have nothing aginst either the NAR or TRA, but I do
feel
that the time has come for the IAR to come forth. 

   I aim to keep the IAR as low cost as I can, with the use of my own
computer
hardware, I hope to keep copys of any forms as files on both floppys
and hard
drive. With the uses of my old 9 pin printer, I'll make any hard copys
at my
cost. The main thing that will cost, will be postage, but even that I
hope to
keep low, only those members that join that have no online service will
get
hard copys. Those with Online E-Mail, will get a copy of this
newsletter in
E-mail.

   BOD, in order to build the IAR and make sure it is run right, we
need to
have a BOD. I would say that 5 members should make up the BOD. As the
members
of the IAR will come from far apart, all of the actions will be done via
e-mail.

   High? Low?  I have been asked just how high in engine power we will
go.
When I formed the IAR, I was mostly thinking of low power rocketry,
that is,
nothing over 'G', but I have taken note that in the members who have
joined,
we have High Power Rocketry people. So! This will be something that we
will
need to have input on. Right now I am willing to say that we could go
at lest
to maybe an I, but this is un-offical right now. I will say this, right
now
anything anyone flys is ok with me until we have the wrtten rules and
limits
set up.

  Dues? As I have posted, for the rest of this year, there are No Dues
to be
paid, this means that at lest 3 more months of free membership. I will
look at
how we are doing during the 1st week of 1996 and will let everyone know
just
what we'll do about dues for 1996.

  Voting, one thing that will be built into the IAR, everyone will have
a vote
on anything that is called up for a full membership vote. 

  Sport? Contest?  I aim to have both, but not one over the other. We
will
have a safty code and a contest code too. In this newsletter I hope to
have
reports on both sport flying and contest flying too.

                           Who Am I?

    Now I will tell you a little about myself. I am Dennis Bishop, I am
46
years old, a partly disabled Vietnam Vet. I live in Waianae,Hi. and I
take
care of my disabled mother. My computer hardware is made up of an Atari
1040ST, one 20 meg hard drive and a ton of floppys. I use a local BBS
named
Muskrats Den for my access to the Usernet news groups. This is my
Internets
entry port. I do not have access to the WWW at all. I do run my own
BBS, but
it is not hooked up to the Internets at all. It is hooked into the ISIS
network, a small network for Atari BBS's.

   I also use CIS, so if you have joined via CIS, then you know my
account
number, you can send e-mail to me that way. If you want to send me
e-mail via
the Internets, you can send it too: [email-masked].

   I have been around Model Rocketry since 1964, back then I could
build a
model rocket, but couldn't fly them in Los Angeles. In 1966 I joined
the Army
and was in there until 1969. I have flown many rockets, but nothing more
powerfull than a 'G' powered bird. I have watched some of the real high
power
launchs and have seen both good flights and total wipeouts too. I have
been a
NAR member in the past, [21288] and I have hosted rocketry meets back
in the
70's too.

  As some of you know, I also have a CIS account, I will upload this
newsletter to the file sig, if anyone can, they can also upload it to
GEINE.

  This is all for this one. If you want to be on the BOD, please let me
know,
plus if you have anything you'id like to see in this please send it in.
I'll
also put in any launch reports you want to have in the newsletter.

                        Dennis Bishop

Article: 19738 of rec.models.rockets
From: [email-masked]
Subject: Re: Plugging booster motors
Message-ID: <[email-masked]>
Date: 8 Oct 95 11:10:39 CST
References: <[email-masked]> <[email-masked]>
Lines: 32

In article <[email-masked]>, [email-masked] (The Silent Observer) writes:
> In article <[email-masked]>, Kevin 
> Forsyth ([email-masked]) says...
>>
>>Is it possible and safe to plug black powder booster motors with 30-min 
> epoxy
>>to make -P's out of -0's?
> 
> My understanding is that this is both possible and about as safe as 
> buying the plugged motors (assuming the motor you want was available as 
> a -P to begin with) -- but may be in violation of the Safety Code non 
> the less, since it constitutes "modifying the motor" in a manner not 
> specifically recommended by the manufacturer.

It is without question a violation of the safety code. It is also quite
possible, and IMHO quite safe. Without endorsing the practice, I do have one
tip I picked up from those experienced with the practice before D11-P motors
were available. Do not use booster motors, but rather one of the delay
motors. The delay acts as a plug to prevent blow-thru, lessening the
pressure and temperature exposure on the epoxy plug. A screwdriver blade
makes an excellent tool to remove both the clay cap and the ejection charge
before plugging. As a side benefit, you now get the delay smoke after
burnout, good for skywriting with RCRGs or whatever.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19739 of rec.models.rockets
From: [email-masked]
Subject: Re: Design Book
Message-ID: <[email-masked]>
Date: 8 Oct 95 11:00:09 CST
References: <[email-masked]>
Lines: 38

In article <[email-masked]>, Tim Van Milligan <[email-masked]> writes:
> Would anyone like information on my hot new book: Model Rocket 
> Design & Construction? If so, send me an email.
> 
> Tim Van Milligan

Unpaid endorsement: a very good book that should be in every rocketeers
library. Even better when you get it the way I did, as a gift from a friend.

A few faults: The entire HPR topic is glossed over. In fact, the book
doesn't mention much outside Estes rocketry, and Estes is the only
manufacturer mentioned. Ironic when you consider the (undocumented) cover
shot. HPR is the only real growth area in the hobby.

The only real fault I found in the book was the BG trimming discussion:
straight out of the 60's. I used to do things that way, as most folks did,
and never had much luck in getting BGs to fly well. I've found that this
leads to a lot of the frustration with gliders, and kept me away from them
for years. I thank a few folks like Guppy and Bunny (and perhaps a few other
animals) for finally pointing me in the right direction.

The proper procedure is to know where the CG is supposed to be (it SHOULD be
documented in the plans but rarely is, because most designers don't know
either), and then use controlled warping of the flying surfaces to get a
good glide profile. The ONLY way to accurately place the CG is to compute
the "neutral point" (the BG equivalent of the CP, in fact the equations for
fins and wings match), decide on a stability margin (% of wing chord,
usually about 20% for free flight models), and put the CG at that point.
Usually, this requires weight on the nose.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19740 of rec.models.rockets
From: [email-masked]
Subject: Re: Igniting flashbulbs?
Message-ID: <[email-masked]>
Date: 8 Oct 95 10:42:26 CST
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Lines: 26

In article <[email-masked]>, [email-masked] (The Silent Observer) writes:
> BTW, the bulbs in a Flashbar (R) (made for Polaroid SX-70 family 
> cameras) appear also to be suitable; they're electrically fired, and the 
> logic to select the bulbs is in the camera, not the bar (unlike the 
> Flip-Flash (R) -- though those bulbs might also work once removed from 
> the assembly).  Flashbars (R) are available anywhere film is sold.  The 
> bulbs are of similar construction to an AG-1B, but are longer and 
> slenderer -- I'd guess that might enhance reliability, since a longer 
> length of thermalite or whatever would be in contact with the bulb 
> surface.

I've used these skinny bulbs to fire FSI F100 and E60 motors directly. Once
removed and the plastic is peeled off, they fit into the nozzle quite
easilly. The heat from the flash is enough to fire the motor without the
need for thermalite. I imagine this would work on the RocketFlite motors
too, but I haven't tried it.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19741 of rec.models.rockets
From: [email-masked] (Robert teed)
Subject: Estes Products Wanted
Date: 8 Oct 1995 17:36:05 GMT
Lines: 8
Message-ID: <[email-masked]>

I am looking for some old Estes Products.
 1. Camroc 
 2. Mars Lander
 3. Transroc transmiter
 4. Any Estes COLDPOWER Rockets and Equipment.
Send Me E-Mail if You have any of these You would like to sell.
 [email-masked]

Article: 19742 of rec.models.rockets
From: [email-masked] (Paul Gray )
Subject: First Arotech Rocket
Date: 8 Oct 1995 18:00:40 GMT
Lines: 26
Message-ID: <[email-masked]>

Hey yo all! I've been checking out the web pages with pictures of
Arotech rocket launches and I have sort of want to build an Arotech
rocket myself. I have been flying Estes rockets for many many years and
have not touched a single rocket made by another company. Anyway, the
things I need to know are:

                            -which kits are best to start out with?
                            -what kind of engines do they use? 
                            -what kind of equipment do I need?
                            -where can I buy engines? 
                            -where can I fly them?

The reason I ask what kind of engines they use is because I am most
familir with Estes engines. I see engines with names like G12 or
something like that. 

As far as equipment is concerned, what kind of launch pad do I need?
Can I fly with an the Estes launch pad I have or do I need to buy a
larger one? If I have to buy a larger one, how much do they cost and
where can I buy them? Also, what kind of launch controller do I need?
How much does it cost and where can I buy that?

Can I fly these rockets at a high school football field or do I need to
go to a more open field? 

I would appriciate any help any of you could give me. Thanks. 

Article: 19743 of rec.models.rockets
From: [email-masked] (Jonathan Sivier )
Subject: Re: Kid groups for Rocktrey
Date: 8 Oct 1995 20:09:49 GMT
Lines: 38
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

[email-masked] (JABeecher) writes:

>Hi, I'm a substitute teacher in ISD #283 in the Twin Cities metropolitan
>area.  A lot of the kids I work with have interest in building and
>launching rockets, but I have no idea who to refer them to.  Are there any
>groups which do parent/child launchings in my area?  Parents ask all the
>time, and although I could invite them to my own launches, there are so
>many I hesitate.  I guess I will if there are no organizations in the
>area...the hobby must go on! 

   One of the members of the Central Illinois Aerospace model rocket club,
Russ Durkee, has just moved to your area.  He was very involved with our
activities of workshops and demos for kids here in Illinois.   He reads this
group and may see this message, but  his email address is [email-masked].
I don't know if there is an appropriate club up there to handle something
like this, but he'd probably know.  If not, perhaps you can get together
with him and some others and form a new NAR section.  I know there is high
power activity there and this probably a Tripoli group, but they may not
be equipped/interested in do stuff with kids other than the occasional demo.
Our group here in Illinois is a combo NAR/TRA section/prefecture and we do
workshops for kids through the local park districts, schools, boys and girls
clubs, cub scouts, etc.  We allow a full range of rockets (up to what the
waiver allows) to fly at all of our launches, so kids are always welcome to
come and fly their Alpha III's (or whatever), even at our high power launches.
It's not unusual to see a 1/2 A fly followed by a K (not that we have that
many Ks flown here, but you get the idea).

Jonathan

----------------------------------------------------------------------
|  Jonathan Sivier          |  Secretary, Central Illinois Aerospace |
|  [email-masked]        |  NAR #56437                            |
|  Flight Simulation Lab    |  Tripoli #1906                         |
|  Beckman Institute        |  Home Address:                         |
|  405 N. Mathews           |    5 The Summit                        |
|  Urbana, IL  61801        |    Champaign, IL 61820                 |
|  217/244-1923             |    217/359-8225                        |
----------------------------------------------------------------------

Article: 19744 of rec.models.rockets
From: [email-masked] (Jonathan Sivier )
Subject: Re: launch report for central Illinois, 9/9
Date: 8 Oct 1995 20:17:21 GMT
Lines: 46
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

[email-masked] (Fred Gruis) writes:

>>The tube you are refering to is from Devcon. I don't recommend this for
>>rocket building or repairs. 5-minute epoxy in general is not very strong or
>>tolerant of heat. It never sets up real hard. After a single flight, the
>>epoxy would be no stronger than the duct tape.

>>        Bob Kaplow                      INTERNET: [email-masked]
>>USPO:   HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
>>TPC:    (708) 241-7919 x5327            ICBM:   41049'48" North 8800'51" West

>>        186,000 Miles per second. It's not the law, it's a challenge!

>>Disclaimer: If this message is caught or killed, the secretary will disavow
>>any knowledge of my actions. These bits will self destruct in 5 seconds....

>Really, I didn't know this...  How do they rate it at 1500 psi??? (some brand 
>I purchased had this info on the container).  What type of failure do you 
>think they are rating????  I don't know if it would stand up to the heat of 
>rocket motor exhaust but it does appear to stand up to cardboard fires.  I had 
>an onboard fire once that burned the body tube halfway down the fin roots 
>before I extinguished it.  The epoxy yellowed but did not burn or let go of 
>the remaining body tube.

   5 minute epoxy has it's uses, but DON'T use it to glue together your motor
mount, especially in high power rockets.  We had a incident here at one of
our launches a few years ago which really illustrated the dangers.  Luckily
no harm was done, but a valuable lesson was learned.  One of our members
launched a high power rocket with a reloadable motor in which he had glued the
motor mount together with 5 minute epoxy.  The heat from the motor was such 
that the glue was melted.  Luckily the rocket recovered Ok, but when he pulled
out the motor the whole motor mount came out as well.  The glue had become
liquid with the heat.  While an Estes motor might not produce enough heat to
make the glue run, it certainly will reduce it's strength.

Jonathan

----------------------------------------------------------------------
|  Jonathan Sivier          |  Secretary, Central Illinois Aerospace |
|  [email-masked]        |  NAR #56437                            |
|  Flight Simulation Lab    |  Tripoli #1906                         |
|  Beckman Institute        |  Home Address:                         |
|  405 N. Mathews           |    5 The Summit                        |
|  Urbana, IL  61801        |    Champaign, IL 61820                 |
|  217/244-1923             |    217/359-8225                        |
----------------------------------------------------------------------

Article: 19745 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Super Vega Body Tube...
Date: 8 Oct 1995 21:52:23 GMT
Lines: 54
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, Bill Nelson ([email-masked]) 
says...
>
>[email-masked] wrote:
>: In article <[email-masked]>, [email-masked] (Bill Nelson) 
writes:
>: > 
>: > One nice thing about reloads is that you can easily tailor the 
ejection
>: > charge to go with the rocket. There is no law that says  you have 
to use
>: > all the powder.  For that matter, if you save up the excess, you 
will 
>: > have some available for the occasional rocket that needs more than 
was
>: > supplied with the reload.
>
>: I keep a 35mm film can in my reload box for storing the excess. You 
don't
>: want a metal container that could accidentally ignite anything when
>: opening/closing...
>
>A metal screwtop film can is probably not a hazard - especially with 
the
>rubber seal they have at the top. After all, black powder is sold in 
one
>pound metal cans.
>

This would be especially true if you can find some of the last 
generation of metal film cans before the general conversion to plastic 
-- they were aluminum, which is about as non-sparking as brass.

On the "bad news" side of this, a couple brands of film now come in 
one-use, peel-top >fiber< cans (same stuff as old oil cans, or Comet 
cleanser cans) that are just garbage after use.  Not reusable for 
anything, AFAIK, not recyclable, and I'd question whether they save 
resources relative to the plastic (though the wood pulp they're made 
from is renewable).

The one brand I remember being packaged this way is Fuji -- but I've 
made myself a mental note to avoid any brand I find with this packaging, 
just on principle.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19746 of rec.models.rockets
From: [email-masked] (PaulDiming)
Subject: Re: Launch Report - Connecticut
Date: 8 Oct 1995 18:12:17 -0400
Lines: 15
Message-ID: <[email-masked]>
References: <[email-masked]>

William,

>>If that happens to you, or you need an inexpensive streamer for 
some other reason, I would recommend trail marking tape. Its 
inexpensive and it comes in different colors.<<

Congrats on flying two great first time fliers.  I lost my Alpha III and
just bought two more.  Great for sending up first to check the wind for
the more elaborate and more expensive rockets.  Good suggestion on the
streamer material.  I also bought 1" stuff at Lowe's hardware for a couple
of bucks.  Bright orange.  Put some on the launch key as a quick way to
check wind direction when its sitting on top of the launch rod.

Paul.
Fly Baby Fly!

Article: 19747 of rec.models.rockets
From: [email-masked] (BRIAN ROBINSON)
Subject: Re: Astrocam reinforcement
Message-ID: <[email-masked]>
Date: Sun, 08 Oct 95 13:51:00 -0800
References: <[email-masked]>
Lines: 12

M(| I first learned this trick from the late Herb Desind some 11 years or
M(| so ago.

I heard that he died. What did he die from and when?

  _______ _______ _______   __                            
 |    .  |    ___|    . _| |  |                  {o o}       W E L C O M E
 |    .  |    ___|       | |__|   ------------ooO-(_)-Ooo-   T O T H E N E
 |_______|_______|____|__| |__|   [email-masked]   X T L E V E L

 * RM 1.3 02952 * Altzheimer's advantage #2: Hiding your own Easter eggs.

Article: 19748 of rec.models.rockets
From: [email-masked] (DBoyd13672)
Subject: How big are they today ?
Date: 8 Oct 1995 19:38:33 -0400
Lines: 4
Message-ID: <[email-masked]>

I have been out of the field for quite a few years. When I left, the
largest commonally available engines were D12s (except for some Es and Fs
by someone called Enerjet). How large have the "run of the mill" engines
become? Who are the suppliers ?

Article: 19749 of rec.models.rockets
From: [email-masked] (C72500)
Subject: Re: Igniting flashbulbs?
Date: 8 Oct 1995 23:13:33 -0400
Lines: 8
Message-ID: <[email-masked]>
References: <[email-masked]>

I will tell you in advance on your flashbulb search... they are getting
scarce! They 
were apparently discontinued sometime back. My best luck has been small,
out of the way convenience stores with 'old' stock. Age does not seem to
effect these as on testing some out of a very faded package, I had to look
at spots for a *long* time. Good Luck, and if you don't have any, let me
know and I can get you some for what I pay. 
  Gary.

Article: 19750 of rec.models.rockets
From: [email-masked] (kingrat)
Subject: Launch report MAGNUM 5
Date: 9 Oct 1995 03:04:40 GMT
Lines: 36
Message-ID: <[email-masked]>

Magnum 5 was hosted by Ross Dunton of Magnum rockets today at the London 
flying site. I don't have access to flight cards, so this will be short. 
The highlights of the day included Jack Thompson's Mother Lode on 3 
K-500s. The big LOC kit left the pad like an Estes model! It was so loud 
it "fuzzed" the mikes on my camcorder. There were many other great 
flights today too including a beautiful scale up of an Estes Interceptor. 
The decals were extremely well done and so was overall construction. 
Perfect boost and recovery, as any rocket with 150 hours of work in it 
should fly. The decals alone took 30 hours to draw and 25 hours to apply. 
Too much for me. Other highlights include Phil Meyer (sp?) with a 5.5 
inch Standard Arm on a core L-750 air starting 2 H-220s. Beautiful flight.
Jack Thompson also flew a King Viper III on 3 H260s. Jim Rossin turned in 
a great flight with a modified LOC Magnum airstarting "H" Silver Streaks. 

Overall I'd say we had over 40 flyers there. Hamburgers, hotdogs, donuts, 
coffee, German sausage were all available on site. The weather was cloudy 
and grey for the first couple hours with a ceiling of maybe 3000 feet. 
Our waiver was to 5000 feet and we got to use it all afternoon. The 
weather cleared up and we had clear blue skies with practically NO WIND 
WHATSOEVER. Amazing. A perfect rocket day in all. Definitely the best 
launch I've been to for a long time.

P.S. Almost forgot a few things. Robby's Rockets was there selling 
electronics and reloadable ejection systems along with the standard fare 
of ignitors and epoxy. I flew a Binder Design "Excel Plus" with a G150SS 
for a good first flight. I also got my Heavy Duty Beauty up with a core 
G64-4 and 4 air started D12-3s. Good flight but the nose snapped back and 
broke off a fin. Go figure.  Russel Rowen (sp?) flew his rocket, the 
Cobra on an H100 and 3 G80s. It rocked. That's about it really. This 
launch will be in an upcoming HPR. I LCO'd the thing but can't remember 
all the flyers names to save myself.....

Eric Specht
Tripoli 1755
Mid Ohio wants YOU!

Article: 19751 of rec.models.rockets
From: [email-masked] (LRocket)
Subject: Re: N2O / Propane Rocket
Date: 9 Oct 1995 02:43:24 -0400
Lines: 32
Message-ID: <[email-masked]>
References: <[email-masked]>

I have built and fired a 700 lbf thrust LOX/propane engine which I found
to have extremely good performance. I measured C* efficiencies in the mid
to high nineties (perhaps a first for amatuer rocketry).  As any decent
atomization/vaporization model will tell you, propane is very easy to
burn.  If you have a decent mixing injector, you can't go wrong - as far
as performance is concerned.  But, also as predicted, throat erosion rate
is very high, unless a fair amount of propane is used as a film coolant.

Because of my success with LOX and propane, I recently built a N2O/propane
rocket and fired it.  In this design, I use the vapor pressure of the
nitrous to pressurize the fuel tank using a concentric piston tank.  I do
not recommend you try this unless you know what your doing.  If the N2O
and propane mix they become a liquid high explosive.  The engine lit and
ran for 4 seconds, with one minor problem. The engine exibited a very high
frequency acoustic instability, also known as scream or screech.  Simple
calculations show that the first tangential or 1-T mode for the chamber is
about 12 KHz, which sounds about right.  I didn't expect an acoustic
instability because of the "inherently stable" injector design I used, but
it didn't suprise me.  Two phase flow is well known for producing
combustion instability, although I expected it would manifest itself in a
less damaging "buzz" mode of instability due to feed system coupling.  Did
I mention damaging?  The injector face and injection elements were burned
pretty good, and the chamber ablative were completely consumed, prompting
a re-design and re-build.  Thats experimental rocketry- test, rebuild,
test.

BTW I agree that ethylene or, preferably, ethane are desireable for their 
similar vapor pressures to N2O, but they are more difficult and expensive
to get ahold of, and one two phase liquid in a bipropellant rocket engine
is trouble enough!

Tom Mueller

Article: 19752 of rec.models.rockets
From: Kevin Nolan <[email-masked]>
Subject: Latest Oldies in Stock
Date: 9 Oct 1995 06:19:28 GMT
Lines: 85
Message-ID: <[email-masked]>

     Here are more newly arrived out-of-production kits we have for sale:

 ESTES
  0831 Star Blazer $19.99
  0863 Starliner $19.99
  0892 Little Joe II $23.99
  1208 Sky Hook $19.99
  1241 Mercury Redstone (balsa cone, wood tower) $59.99
  1248 Bandit (ducted ejection) $39.99
  1265 Scissor-Wing Transport $49.99
  1350 Black Hole Space Probe $37.99
  1373 Soaring Eagle (Flex-wing glider) $49.99
  14?? Gemini Star Raiders Starter Set (Gnome, Leprechaun) $29.99
  1961 Crusader Swing-Wing Glider $49.99
  1974 Explorer $19.99
  1981 D.A.R.T. $15.99
  1997 Pathfinder $21.99
  2003 SDI Satellite $27.99
  2038 Alien Space Probe $25.99

 Catalogs
  1974 $29.99

 Decals
  KD-52A for Omega $9.99
  37215 for ? "JL5", etc. $1.99
  37220 Stinger $1.99
  37227 for Airborne Surveillance Missile $4.99
  37242 for Aries SST $6.99
  37294 for Geo Sat LV $6.99
  37387 for Mini Mars Lander (small cutout) $2.99
  37458 for Silver Streak $4.99
  37465 for ? (like longer Starliner) $6.99
  37489 for Saturn 1B $9.99
  37516 for Soaring Eagle $9.99
  37598 for for Starship Nova $9.99

 Model Rocket News Magazines
  June 1970 $14.99
  June 1971 $14.99
  January 1972 $14.99
  October/November 1974 $14.99

 ESTES/VASHON
  5122 X-13 Cold Power Rocket Plane set $99.99
  5123 Astro-Gnat Cold Power Rocket Plane set $119.99

 CENTURI

  KA-5 Micron $15.99
  KC-50 Laser-X $59.99
  SPA-4 Beginners Special (parts) $29.99
  2150 Evel Knievel Sky Cycle $39.99
  5031 Stiletto $29.99
  5314 Space 1999 Eagle Transporter Starter Set $59.99
  5334 Buck Rogers Earth Forces Laser Lance $23.99

 Corrugated Body wraps for Quasar (Saturn-ish) set of 2: $4.99

 Catalogs
  1969 $39.99
  1978 Dealer's $16.99

 Decals
  IP-266 Silver Service Module wrap for Saturn kits $9.99
  M-339 for Taurus kit $9.99
  for Scram-Jet kit $9.99

 American Rocketeer magazine (Centuri's MRN)
  Vol.4 #11 $14.99

 Full Color Poster of Centuri kit line 13" x 26" $9.99

 CANAROC
  Space Modeler Magazine. Winter 1982, Vol.1, #1 $9.99

 World Spacemodeling Championship publication, 1980 $5.99

     To order or get more info, please contact by appropriate method below.

-- 
"3"     Kevin Nolan      Countdown Hobbies; 74640,[email-masked]
"2"     NAR 16148        800/810-0281; 203/790-9010 (24 hr. voice/fax)
"1"     TRA 0943         3 P.T. Barnum Square, Bethel, CT 06801-1838
"0"     NARCONN/CTRA         "Put Fun & Excitement in Your Life"

Article: 19753 of rec.models.rockets
From: [email-masked] (JABeecher)
Subject: Launch Report Questions
Date: 9 Oct 1995 04:12:57 -0400
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]>

I am new to the Internet rocketry scene, so I wondered about the launch
reports I have been reading.

I enjoy reading them, and would like to report the activities of the
Minneapolis Space Program's attempts at experimentation and launch.  Do we
have to be an official organization?  Is there a standard format?

Our organization is recreation and fun oriented, so my reports may not be
too serious.  They will, however, be fun.

Article: 19754 of rec.models.rockets
From: [email-masked] (William )
Subject: US Rockets "Dream Machine" kit, a review (part 1)
Date: 09 Oct 1995 09:48:51 GMT
Lines: 83
Message-ID: <[email-masked]>

Well, I was curious, wanted a 3" payloader, and figured I didn't have much
to lose anyway, so late Sunday night (20-Aug) I sent off an order to Jerry
Irvine for a "USR Dream Machine" Rocket kit, on his "pay when it arrives"
plan.  It arrived on Saturday (26-Aug.)  So far so good.

Here's the description of the finished model, editted somewhat from
Jerry's description (more about that later.)

    U.S. Rockets Dream Machine
    66mm host mount payload rocket

    Diameter: 3.16"				   Price $60
    Overall Length: 58"
    Motors: 66mm host
    54mm conversion			     
    29mm conversion			           Recommended Motors  
    accepts 3-29mm, 38mm or 4-24mm mounts          54mm                
    Recovery: Parachute			           I140-12    I65-12   
    Approx Wt: 2.5 lbs			           I200-8FS   J125-12  
    Payload length: 24"			           3-29mm              
					           G30-8  H60-12  H320-12
    Materials:				           4-24mm              
    Airframe: Spiral wound paper virgin white      D12-5  D12-0/D12-5  
    Nose cone: Blow molded plastic	           F25-8  H100-12      
    Fins: 5-ply or better birch plywood	                               
    Mounting: Through the wall		           Minimum Power       
    Launch Lugs: Mylar sliders		           G60-8               

I was particularly attracted to the especailly large payload section, and
the interchangable motor configurations.  This is only my second mid-power
kit (the previous being approximatelyy an Aerotech Arreaux).  I figured
sticking with paper tubes, and going to plywood "other parts" was a good
step as well.  Other rockets under consideration included the Brutus
(recently denigrated because of small payload section) and the Excel-plus
(the stretch Brutus.)  At 4 inches in diameter, both were a little larger
than I was hoping for, and a little large for my field.  In the end, I
suppose curiosity and the ability to order by email decided me in favor of
the USR "Dream Machine".

Initial impressions:

The main body of the rocket is composed of two pieces of heavy-wall white
three inch tubing, each 24 inches long.  One tube is will be the payload
section, and one the motor/fins/recovery section.  "Virgin white" apparently
means that the paper used for the tubes is ALL white, rather than just the
outer layer (as in LOC/Aerotech/etc.)  The 3" tubing has a very heavy wall,
thicker than LOC tubing I've seen, but it's not as thick as my "found"
plotter paper cores.  It is thick enough that the nosecone doesn't quite
make a smooth joint, but some sandpaper will fix that.  Although something
struct me as odd about the tubes, it took me a while to realize that unlike
most rocket tubing, these do not have a shiny glassine coating layer.  This
is an interesting trade-off - It ought to make glue joints stronger, but
will complicate painting somewhat.  (Out comes the fill&finish!)

The "Interchange mount" is simply a large motor mount tube into which
adaptors are friction-fit using tape.  I suspect I'll be adding some
hardware here to ensure motors and mounts don't eject.  The host tube is 12
inches long, the 54mm mount 9 inches long, and the 29mm adaptor is 6 inches
long.  I'm not entirely sure whether this limits the length of motor that
may be used, since there are no clips or "thrust rings".  (The instructions
call for masking-tape thrust-rings on the motors themselves, which seems
to be well accepted practice.)

I'll have to cut the TTW slots for the fins myself, which might be
interesting.  The large diameter motor mount does not lend itself to
leaving a centering ring off in order to apply internal fillets, but I
have some other ideas to pursue for strengthening the fin joints...
ly internal fillets, but I
have some other ideas to pursue for strengthening the fin joints...

The most disappointing aspect of the kit is that it lacks a parachute.  The
$60 price was apparently a discount based on the parachute being missing,
but the added cost of a chute (a 30" X-form chute is recomended) will push
the price of kit up over most of it's close competitors.  (On the other
hand, I recently acquired a couple extra chutes from a core-sampling rocket
whose owner was too depressed to salvage parts...)

[Part 2 will appear when I'm further along, and will include interesting
 tidbits (if any) gleaned during construction, comments on non-standard
 modifications I implemented, and (hopefully) a launch report.]

BillW

Article: 19755 of rec.models.rockets
From: [email-masked]
Subject: Re: Kits, Kits, Kits - Fin Attachment
Date: 9 Oct 1995 14:29:10 GMT
Lines: 31
Message-ID: <[email-masked]>
References: <[email-masked]>

>
>  I have two questions (couldn't find this information in the FAQ):
>  1) I assume you are using a "needle" or "pin" to create the holes.
>     How many HPI (Holes Per Inch) do you use?  I speculate that if
>     the HPI is too dense you would actually weaken the structure.
>  2) What is the "rivet" method?
>
>
>  Thanx in advance, 
>  M.Howe
>  YABAR
>  "Eschew Obfuscation"
>
>
> 
OK, here are two answers...
 To make the holes I use either a drill, or a very sharp exacto knofe. It really depends on the type of tubing. For PML, G-10 etc... a drill 
works best. For estes tubing, an exacto knive should be ok. Make the holes the same diameter as the width of the root edge of your fin. 
These should not be small holes. I made that mistake once, and have to rebuild my Onxy.

As far as how many holes per inch. This also depende on the rocket. Usuall. I'll do about 1 hole per inch on the larger models ( My 'No 
Questions Asked [NQA], or a Expideter) but might go to 2 per inch on my Onyx. As far a weekening, well, I have yet to have fins break 
off ona rocket that I have riveted and taped.  Take the launch of NQA at the last TARA launch, the delay caught before the motor did. 
50 ft in the air it blew..... and the 32" chut deployed ( Ya, it was a big chut for a 5ft 2.6" rocket... but helll it was only a G104) BAM, and a 
hard landing.... no broken parts, just an estes dent which I latter plan to fix with riveting some tape to the body.

The about is the rivet methog.

Article: 19756 of rec.models.rockets
From: [email-masked] (Judge LI)
Subject: Re: Epoxy Setting (was:Re: Could someone help with my Phoenix c.p. question ???)
Date: 9 Oct 1995 12:30:43 -0400
Lines: 8
Message-ID: <[email-masked]>
References: <[email-masked]>

>>At an air temp of 95 F, epoxy in a plastic cup gets hot enough when it
sets to 
>>cause first and second degree burns. The temperature rise is quite 
>>significant. Haven't seen it melt a cup, but it wouldn't surprise me.

I've seen the cup melt - I was just screwing around and wanted a nice hunk
of epoxy so I poured it into a plastic cup and after a few minutes the
stuff started to melt and smoke and a whole bunch of nasty stuff. 

Article: 19757 of rec.models.rockets
From: [email-masked] (Jason L. Eckhardt)
Subject: G125? and Whatever happened to...
Date: 9 Oct 1995 13:22:12 -0500
Lines: 17
Message-ID: <[email-masked]>

I've recently got myself back into rocketry. My favorite models 5-7 years
ago were Estes Red Max, Estes Maxi-Icarus, and Estes Goblin. I've been to
every hobby shop
and I don't see any of these anymore. Does Estes still make these?

I also think estes has some of the neatest designs. I would like to build
high-power replicas of the 3 mentioned above. Anybody out there built any
estes replicas in the mid- or high-power variety? 

With different fins and a paint job, the LOC/Precision EZI-65 could look very
much like a large red max, what do you think?

On a different note, I recently built a loc ezi-65 and I would like to test
fly it with the least power. They mention a G125 on the spec sheet as the 
smallest engine, but I've not been able to find one. The closest thing I've
seen is G104 (Aerotech RMS). Where do I find G125? Or would G104 be sufficient?

Article: 19758 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Launch Report Questions
Date: 9 Oct 1995 18:51:33 GMT
Lines: 37
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, JABeecher 
([email-masked]) says...
>
>I am new to the Internet rocketry scene, so I wondered about the launch
>reports I have been reading.
>
>I enjoy reading them, and would like to report the activities of the
>Minneapolis Space Program's attempts at experimentation and launch.  Do 
we
>have to be an official organization?  Is there a standard format?
>

No, and no.  We'd love to see reports of launches, including successes, 
indications of what kits you like and don't like to launch, damage if 
any (and damage mode and cause, if you know), motor failures and failure 
modes if any, and descriptions of any unusual flights, good or bad.
That's part of what this grouup is about!  B)

>Our organization is recreation and fun oriented, so my reports may not 
be
>too serious.  They will, however, be fun.
>

The only people taking things too seriously here are the NAR and TRA 
politicians -- and some of us, at least, just ignore those threads.  I 
>never< ignore a launch report...  B)

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19759 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: How big are they today ?
Date: 9 Oct 1995 18:05:59 GMT
Lines: 55
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, DBoyd13672 
([email-masked]) says...
>
>I have been out of the field for quite a few years. When I left, the
>largest commonally available engines were D12s (except for some Es and 
Fs
>by someone called Enerjet). How large have the "run of the mill" 
engines
>become? Who are the suppliers ?

While Estes is still doing very well selling motors from 1/2A through D 
(they introduced an E, but it was pulled from the market due to a 
tendency to explode -- it's supposed to be back within the next few 
months; they also discontinued the 1/4A motors in both standard 18mm and 
Mini configurations a couple years ago), there are a few companies 
producing and selling larger motors now, with motors up to G impulse 
generally shippable UPS and requiring no special qualification for 
flight -- these motors generally run to approximately $12-$15 retail, 
each, in expendable, but are also available in 24mm (Estes D diameter) 
and 29mm reload kits for around $8 per reload (after you buy the 
reloadable motor, for $40 to $70).

Larger motors are also somewhat commonplace; the Aerotech Reloadable 
Motor System (RMS) is available in up to 54mm diameter, which will take 
reloads through at least K impulse, though reload kits beyond H and a 
few I motors, or larger than 38mm, require special arrangements for 
transport and a Federal Low Explosive User Permit and approved magazine 
to store (this is not a detailed or exact representation of the 
situation on this -- that's available in the FAQ).  There are also a few 
expendable motors available, and other reload systems, that support 
impulses in "standard" motors into the M class before gradating into 
amateur-built motors, of which a few are flown each year at a couple 
special meets in Nevada, ranging to P, Q, R, and even (at least once 
that I've heard of) S impulse.

FWIW, the Estes 1/2A through D motors account for in excess of 90% of 
the motor sales in the US each year, and a lot of people fly Estes-class 
rockets for years without ever realizing that larger motors are around. 
 That's due to change soonish, with the recent acquisition by Estes of 
North Coast Rocketry, which is to include designs and/or tooling for 
composite propellant motors (as opposed to the Estes-type pressed black 
powder) up to G impulse, as well as a number of kit designs to take 
advantage of these larger motors.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19760 of rec.models.rockets
From: [email-masked]
Subject: North Coast Rocketry Stiletto B Boost Glider
Date: 7 Oct 1995 20:54:29 GMT
Lines: 10
Message-ID: <[email-masked]>

Today I flew my Stiletto B on a C6-5 (estes) after building a new pod, 
and now I have lost the glider (after a 3:10.08 flight time) in tall 
grass.  The Flourescent Orange paint didn't help me find it!

After hearing this tale of woe, would some fine fellow modeller be kind 
enough to tell me that they have a set of plans for the kit?  It seems 
the glider and pod are NOT the only things I have lost!!!!

Thanks in advance.

Article: 19761 of rec.models.rockets
From: [email-masked] (Michael Edelman)
Subject: Jetex fuel comp, pt. II
Date: 9 Oct 1995 18:28:48 GMT
Lines: 17
Message-ID: <[email-masked]>

A while ago we had a brief discussion fo the composition of Jetex
fuel. I have another data point. According to "Rocket Propulsion
Elements", 3rd ed, by G. Sutton (Wiley & Sons, 1964)

"Mixtures of ammonium nitrate and guanadine nitrate with appropriate 
catylysts for decomposition are used for small rockets which propel
small model aircraft. Loose powder is consolidated nder high pressure
(perhaps 7000 lb per sq in.) into suitible molds. The finished charge 
is hard and rock-like in appearance."

I wonder what the catalyst is?  I suspect a metal oxide, but I don't
have any further evidence. What color is pure guanidine nitrate?

It does sound like it would be simple enough to make pellets with my 
benchtop arbor press. 

--mike

Article: 19762 of rec.models.rockets
From: [email-masked] (Mick Ishmael)
Subject: Re: G125? and Whatever happened to...
Date: 9 Oct 1995 12:54:29 -0700
Lines: 14
Message-ID: <[email-masked]>
References: <[email-masked]>

Jason L. Eckhardt ([email-masked]) wrote:
: I've recently got myself back into rocketry. My favorite models 5-7 years
: ago were Estes Red Max, Estes Maxi-Icarus, and Estes Goblin. I've been to
: every hobby shop
: and I don't see any of these anymore. Does Estes still make these?

NOPE.

: I also think estes has some of the neatest designs. I would like to build
: high-power replicas of the 3 mentioned above. Anybody out there built any
: estes replicas in the mid- or high-power variety? 

I built a 3.2:1 Goblin scale-up <4" airframe>. Flies on I211s and is a 
real crowd pleaser. I might fly this on an I284 next year.

Article: 19763 of rec.models.rockets
From: [email-masked] (Michael Edelman)
Subject: Re: Jetex fuel comp, pt. II
Date: 9 Oct 1995 19:11:49 GMT
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]>

I wrote:

: A while ago we had a brief discussion fo the composition of Jetex
: fuel. I have another data point. According to "Rocket Propulsion
: Elements", 3rd ed, by G. Sutton (Wiley & Sons, 1964)

: "Mixtures of ammonium nitrate and guanadine nitrate with appropriate 
: catylysts for decomposition are used for small rockets which propel
: small model aircraft. Loose powder is consolidated nder high pressure
: (perhaps 7000 lb per sq in.) into suitible molds. The finished charge 
: is hard and rock-like in appearance."

: I wonder what the catalyst is?  I suspect a metal oxide, but I don't
: have any further evidence. What color is pure guanidine nitrate?

Further reading specifies that a chromite was used.

--mike

Article: 19764 of rec.models.rockets
From: "Chris Kachelmyer" <[email-masked]>
Subject: Fins for Scratch built?
Message-ID: <[email-masked]>
Date: Mon, 9 Oct 1995 13:10:56 GMT
Lines: 19

> I was wondering if there were any companys that sell fins alone. since i
> have no access to any adequit cutting devices, i would have to buy some,
> or pay some one to cut them. Any information would help a great deal

Well, it depends on what kind of fin you want, but PML sells G10 fins. 
Precut, that is.

========================================================================
Chris "the Giant" Kachelmyer     "I'm your only friend, I'm not
[email-masked]       your only friend, but I'm a 
                                  little glowing friend, but 
                                  really I'm not actually your 
                                  friend, but I am."
                                            
                                              --They Might Be Giants
"So from me, Harrold, and all the other guys up here at the lodge, 
 keep your stick on the ice."
                                 --Red Green "The Red Green Show"

Article: 19765 of rec.models.rockets
From: [email-masked] (Stefan E. Jones)
Subject: Re: G125? and Whatever happened to...
Date: 9 Oct 1995 14:21:40 -0500
Lines: 33
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>,
Jason L. Eckhardt <[email-masked]> wrote:
>I've recently got myself back into rocketry. My favorite models 5-7 years
>ago were Estes Red Max, Estes Maxi-Icarus, and Estes Goblin. I've been to
>
I think these are long gone.

>I also think estes has some of the neatest designs. I would like to build
>high-power replicas of the 3 mentioned above. Anybody out there built any
>estes replicas in the mid- or high-power variety? 
>
"Original Rockets Inc." produced "Der Blue Max" a few years back.  It may
still be available.  It's a nice model, but I replaced the surface-mount
fins with the through-the-wall variety (actually, I used the same fins,
but added a tab on the side of each; this ran through the tube to the 
engine mount).

I've seen big Goblins.  I forget what the Icarus looked like.
>With different fins and a paint job, the LOC/Precision EZI-65 could look very
>much like a large red max, what do you think?
>
>On a different note, I recently built a loc ezi-65 and I would like to test
>fly it with the least power. They mention a G125 on the spec sheet as the 
>smallest engine, but I've not been able to find one. The closest thing I've
>seen is G104 (Aerotech RMS). Where do I find G125? Or would G104 be sufficient?
> 

The average impulse seems close enough . . . does the G104 have the same
total impulse? (I think the G125 had a total impulse of 120-125 ns.)

The G125 was/is a "nonstandard" Aerotech motor, still available but not
through hobby stores that carry just the "consumer" line.  I bet Kevin
Nolan coupld help you with this one.

Article: 19766 of rec.models.rockets
From: [email-masked] ( Frank J. Burke 8923767 )
Subject: Re: G125? and Whatever happened to...
Date: 9 Oct 1995 20:20:02 GMT
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>,
Jason L. Eckhardt <[email-masked]> wrote:
>I've recently got myself back into rocketry. My favorite models 5-7 years
>ago were Estes Red Max, Estes Maxi-Icarus, and Estes Goblin. I've been to
>every hobby shop
>and I don't see any of these anymore. Does Estes still make these?
>
>I also think estes has some of the neatest designs. I would like to build
>high-power replicas of the 3 mentioned above. Anybody out there built any
>estes replicas in the mid- or high-power variety? 
>
>With different fins and a paint job, the LOC/Precision EZI-65 could look very
>much like a large red max, what do you think?

Well, Original Rockets makes a Das Blue Max, which is a 4" body tube
version of 
the Estes Red Max, complete with decals.  I think Countdown has it,
although it is around $60-70.

NCR at one time was making the Hobgoblin(I think) a 7" body version of
the goblin.  Estes no longer makes the originals, but Countdown may have
some.  On a trip to France last year, I found a Red Max, and an X-15 in
a hobby shop in Paris.  My wifes family was quite impressed with
rocketry, since although it is available, it is not widely known.

Frank

>

Article: 19767 of rec.models.rockets
From: [email-masked] (Bill Nelson)
Subject: Re: Igniting flashbulbs?
Date: 9 Oct 1995 04:47:39 GMT
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

March A. Briner ([email-masked]) wrote:

: Why bwould you want to shove a e-match in an F or G? Not highly 
: necessary, but if you really find that it is...

They come in handy when the launcher battery is dying, and there is no
replacement. They require far less current than wrapped Thermalite or
(shudder) a Copperhead.

Bill

Article: 19768 of rec.models.rockets
From: [email-masked] (Bill Nelson)
Subject: Re: How big are they today ?
Date: 9 Oct 1995 05:12:50 GMT
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]>

DBoyd13672 ([email-masked]) wrote:
: I have been out of the field for quite a few years. When I left, the
: largest commonally available engines were D12s (except for some Es and Fs
: by someone called Enerjet). How large have the "run of the mill" engines
: become? Who are the suppliers ?

For Model Rocketry, the largest is a G. For High Power Rocketry, anything
up through a K is pretty much "run of the mill".

Bill

Article: 19769 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: Mean Machine?
Date: 9 Oct 1995 21:02:40 GMT
Lines: 30
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

John Kestner ([email-masked]) wrote:
: Mark Travis ([email-masked]) wrote:
: : Sorry about the first blank post....
: : *************************************
: : My daughter and I are also in the process of building a Mean Machine --
: : (we've seen several fly successfully) -- but I'm considering a modification
: : and wonder if anybody else has done the same.  Since I don't want to
: : take the family wagon to every launch, I was thinking of splitting the
: : Mean Machine in the middle and using a nose block for the bulkhead.
: : Does anybody know if Balsa Machining Service makes a nose block for
: : Estes BT-60 tubing?  Am I creating more problems just so I can fit
: : it into the back seat of my compact car?

: That's exactly what I did (and for that same reason). But all I did was
: use the tube coupler to fit the halves together and epoxy two shock cords,
: one on the end of each half. They each have their own parachute (I really
: don't recommend tying such long halves together). Works great.

BMS custom turns nose cones, transitions, etc.  So, you can have virtually
anything made since you supply the dimensions.  You need to get their
order form since it has special instructions on how to specify your part.

Estes sized stuff is pretty reasonable, but when you get up to the 3-4"
size, be prepared to pay over $20 for parts.  The small stuff varies 
from under a dollar to a few dollars per part.  BT-60 sized parts are
in the $4-5 range, if I recall.  I don't have price sheet handy.
--
Lee Reep 
 [email-masked] 

Article: 19770 of rec.models.rockets
From: [email-masked] (Jonathan Sivier )
Subject: Re: G125? and Whatever happened to...
Date: 9 Oct 1995 21:12:19 GMT
Lines: 38
Message-ID: <[email-masked]>
References: <[email-masked]>

[email-masked] (Jason L. Eckhardt) writes:

>I've recently got myself back into rocketry. My favorite models 5-7 years
>ago were Estes Red Max, Estes Maxi-Icarus, and Estes Goblin. I've been to
>every hobby shop
>and I don't see any of these anymore. Does Estes still make these?

>I also think estes has some of the neatest designs. I would like to build
>high-power replicas of the 3 mentioned above. Anybody out there built any
>estes replicas in the mid- or high-power variety? 

>With different fins and a paint job, the LOC/Precision EZI-65 could look very
>much like a large red max, what do you think?

>On a different note, I recently built a loc ezi-65 and I would like to test
>fly it with the least power. They mention a G125 on the spec sheet as the 
>smallest engine, but I've not been able to find one. The closest thing I've
>seen is G104 (Aerotech RMS). Where do I find G125? Or would G104 be sufficient?

   I've flown my EZI many times on G64-4 reloads, the G80-4 (or is it -5?) will
work fine as well.  Without the payload section mine weighs almost exactly
3.3 lbs so you wouldn't need a waiver, just notification.  I've heard that the
Aerotech G104 can be used, but the short delay is ~6 secs and it's barely a
G (just over 80 nt-secs) so I, personally, would be hesitant to use it on that
rocket.  I've flown G104's before on lighter rockets and they work fine, but
I think the EZI might be a bit heavy for that motor/delay.

Jonathan

----------------------------------------------------------------------
|  Jonathan Sivier          |  Secretary, Central Illinois Aerospace |
|  [email-masked]        |  NAR #56437                            |
|  Flight Simulation Lab    |  Tripoli #1906                         |
|  Beckman Institute        |  Home Address:                         |
|  405 N. Mathews           |    5 The Summit                        |
|  Urbana, IL  61801        |    Champaign, IL 61820                 |
|  217/244-1923             |    217/359-8225                        |
----------------------------------------------------------------------

Article: 19771 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: LOC 4 Sale
Date: 9 Oct 1995 21:07:26 GMT
Lines: 18
Message-ID: <[email-masked]>

The latest HPR has a full page ad telling interested folks to
contact LOC if you want to receive "an informative perspective
package" (prospectus?).

Ad reads:

So ... you want a sneak preview for 96?

Preview This!

LOC/PRECISION is For Sale ...

I'm sick of my job, anyone wanna go half'sies?  :)

--
Lee Reep 
 [email-masked] 

Article: 19772 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: Could someone help with my Phoenix c.p. question ???
Date: 9 Oct 1995 21:20:53 GMT
Lines: 21
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

[email-masked] wrote:

[discussion of adding weight to nosecone...]

: > In practical terms,  I epoxied two extra lumps of clay ( a total
: > of three ) into the nose cone with 5-min epoxy.  Someone correctly
: > pointed out I should have used 15 or 30 minute epoxy because the nose
: > got **hot** while the cement cured.

: Ah, yes, I didn't say this, but thought it while entering my last reply.
: Epoxy in large blobs can be quite exothermic when setting, and can damage
: plastic when it sets...

I've used Slow Cure and not noticed any (detectable anyway) heating of
the plastic, but you can set epoxy filled nose cone in the appropriate
diameter jar of water to keep the plastic cool while the epoxy is curing.

--
Lee Reep 
 [email-masked] 

Article: 19773 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: Fins for Scratch built?
Date: 9 Oct 1995 21:35:46 GMT
Lines: 21
Message-ID: <[email-masked]>
References: <[email-masked]>

MonkyTrama ([email-masked]) wrote:
: I was wondering if there were any companys that sell fins alone. since i
: have no access to any adequit cutting devices, i would have to buy some,
: or pay some one to cut them. Any information would help a great deal
: Thanx
: Matt

Nothing elaborate needed.  Go to your hobby store and purchase an Xacto
Razor saw.  You will want both the coarse and fine blades.  You can cut
up to 1/4" fins with these -- I've done it.  Takes awhile, but it does
work fine.  Their are companies that sell fins, but you'll pay plenty,
and only a few might do custom.  Otherwise, you buy the styles they
sell.

Also, you can cut the fins on top of a scrap piece of wood, or other
surface that can be cheaply obtained, such as paneling, masonite, etc.

--
Lee Reep 
 [email-masked] 

Article: 19774 of rec.models.rockets
From: [email-masked] (Iskandar Taib)
Subject: Re: Iron-on covering
Date: 9 Oct 1995 22:09:31 GMT
Lines: 41
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>,
Larry Klug  <[email-masked]> wrote:

>I recently completed a couple of RC BG projects using low temperature 
>iron-on covering for finishing.  The results are far better than filling 
>and painting.  No preparation is required other than sanding.  Also, 
>filling and painting adds loads of weight and no strength!  A good 
>iron-on coverling adds significant strength to the structure with less 
>weight than paint & fillers.  Paint actually weighs more after it dries, 
>because as paint dries, the solvent molecules are released into the air 
>and long chains of oxygen molecules attach themselves to the paint 
>molecules, making the paint dry and insolvent and heavier!

Umm.. I don't think any paints do this. Most lose weight as the
solvents leave. Some do polymerize when exposed to air, and may indeed
absorb some oxygen, but I doubt its very much..

>For years I have followed the Estes balsa filler dogma.  My question is, 
>why don't people use iron-on covering for fins and body tubes of 
>rockets?

Might be OK for rockets (I find a can of spraypaint is a lot more
convenient) but for BG's the reason is perhaps the same as why Free
Flighters don't use iron-ons - they're just way too heavy. A good
tissue-and-dope job can be far lighter then all but the lightest of
the plastics (i.e. Litespan). 

As for adding strength - you're supposed to use tissue and dope rather
than just paint. You won't believe how much strength tissue and dope
add..

-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: [email-masked] |    Frog is Frog ala Peach
Home page: http://bigwig.geology.indiana.edu/iskandar/isk2.html

Article: 19775 of rec.models.rockets
From: [email-masked] (Iskandar Taib)
Subject: Re: Thermalite
Date: 9 Oct 1995 22:11:57 GMT
Lines: 27
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, Bill Nelson <[email-masked]> wrote:
>Paul Hamilton ([email-masked]) wrote:
>: I'm getting back into modeling again (just completed and flew a
>: scratchbuilt C altitude the other weekend).  I started in 1958 and stopped
>: in 1969.  One question -- just what is Thermalite? Is it the same as Jetex
>: fuse? (Jetex fuse was a copper wire coated with a flexible brown incendiary
>: substance and was the standard Model Missiles and Estes igniter utill the
>: 1970's). 
>
>It is somewhat similar. Thermalite uses a "Thermite" type coating over the
>flexible copper wire - and has a number of nichrome wires spiral wrapped
>around the lengh - as well as a bit of some type of thread.
>
>It burns much hotter, and a lot faster, than the Jetex fuses.

Incidentally, Jetex fuse, fuel, models, etc. is available again from
DARE designs (see Flying Models magazine for ads).

-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: [email-masked] |    Frog is Frog ala Peach
Home page: http://bigwig.geology.indiana.edu/iskandar/isk2.html

Article: 19776 of rec.models.rockets
From: [email-masked] (Iskandar Taib)
Subject: Cheap battery alert
Date: 9 Oct 1995 22:33:49 GMT
Lines: 27
Message-ID: <[email-masked]>

I was at the local Wal-Mart last night, and they had Eveready A76
alkaline button cells really cheap - a PAIR for, I think, $1.30 or
so. These cells put out 1.5 volts and are used in the Tower Hobbies
tach (it needs 4 - my tach's batteries had run down) and in some
cameras (makes a good replacement for the MS-76 silver cell, which
costs 4 times as much - works great in my Ricoh XR2s).

I can see all kinds of uses for these things - micro RC, tiny Free
Flight model locators, flashbulb ignitors for second stages, night
recovery beacons..

Where in the store are these batteries? Well, in the fishing
department. They sell them to use with night bobbers..

Mind you, better buy some quick. If you keep them in the fridge with
some dessicant, they should last a while. The Kevlar and Spectra
fishing line that Wal-Mart was selling last year aren't being sold any
more.

-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: [email-masked] |    Frog is Frog ala Peach
Home page: http://bigwig.geology.indiana.edu/iskandar/isk2.html

Article: 19777 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: Re: Video camera fitted in rocket
Date: 9 Oct 1995 22:45:21 GMT
Lines: 23
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

[email-masked] (Ryan Brooks) wrote:
>In article <[email-masked]> John Dunbar
><[email-masked]> writes:
>> Send me an address and I'll send you a catalog with ATV 
>> products in it.  We design and build boards for R/C Air Craft,
>> submersable vehicles, and of course, model and amature rockets.
>> 
>> -- 
>> John Dunbar
>> KE6WBO
>
>Anyone have a favorite source for cheap, small CCD cameras?
>
>Ryan Brooks
>[email-masked]

Well, the cameras I buy are bought through Polaris (310) and 
Super Circuits ( Texas ).  Don't have the catalogs here at 
work with me.  Average cost for b/w ~$125.00, color ~$350.

-- 
John Dunbar

Article: 19778 of rec.models.rockets
From: [email-masked] (William Walby)
Subject: Re: G125? and Whatever happened to...
Date: 9 Oct 1995 23:55:39 GMT
Lines: 16
Message-ID: <[email-masked]>
References: <[email-masked]>

Jason L. Eckhardt ([email-masked]) wrote:
: I've recently got myself back into rocketry. My favorite models 5-7 years
snip
: On a different note, I recently built a loc ezi-65 and I would like to test
: fly it with the least power. They mention a G125 on the spec sheet as the 
: smallest engine, but I've not been able to find one. The closest thing I've
: seen is G104 (Aerotech RMS). Where do I find G125? Or would G104 be 
sufficient? 

I fly my EZI-65 all the time without the payload section on a G64-4 
reload. Makes for a very nice flight on small fields. If you don't have 
an RMS then it would probably fly just fine on a G80-4.
Enjoy

William 

Article: 19779 of rec.models.rockets
From: <[email-masked]>
Subject: Rocket Fuel - Composite Propellant
Date: 10 Oct 1995 03:02:25 GMT
Lines: 15
Message-ID: <[email-masked]>

 <[email-masked]> writes:
>
> Roger Thomas <[email-masked]> writes:
>>wanted any fuel recipes please!
>
>Send me your mailing address and I will send you a catalog on our books, materials and
>instrumentation we sell to make composite rocket motors.
>
>John Wickman
>CP Technologies
>
I have received many requests for catalogs and information.  I will be sending the 
information our this week if you have sent me your mailing address.

Article: 19780 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: N2O / Propane Rocket
Date: 10 Oct 1995 02:56:47 GMT
Lines: 5
Message-ID: <[email-masked]>
References: <[email-masked]>
	<[email-masked]>

Shouldn't you be able to pressurize the Propane take with CO2 and get
very similar characteristics to N2O?  Hmm.  Are liquid CO2 and N20
mutually soluble?

BillW

Article: 19781 of rec.models.rockets
From: Matthew Joseph Rosenwasser <[email-masked]>
Subject: American Sci and Surplus Info
Date: Mon, 9 Oct 1995 22:38:57 -0400
Lines: 16
Message-ID: <[email-masked]>

	American Science and Surplus Info:
	3605 Howard St.
	Skokie, IL  60076
	Tel: 708-982-0870

	Emery boards, pilot parachute, rod balsa wood, launch switch,
	modelling kit and disposable scapels are all in Volume 87.  They
	should be able to send you a catalog.  I believe that they have
	paints and glues as well, but I did not get them.  Keep in mind
	that this stuff is surplus and therefore they may run out of 
	some things when you order.

	Cheers all -

	Matt

Article: 19782 of rec.models.rockets
From: [email-masked] (Robert K. Gormley)
Subject: Re: G125? and Whatever happened to...
Date: 10 Oct 1995 01:44:18 GMT
Lines: 19
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> [email-masked] (Jason L. Eckhardt) writes:
>
>On a different note, I recently built a loc ezi-65 and I would like to test
>fly it with the least power. They mention a G125 on the spec sheet as the 
>smallest engine, but I've not been able to find one. The closest thing I've
>seen is G104 (Aerotech RMS). Where do I find G125? Or would G104 be sufficient?
> 

The G125 is an Aerotech non-standard Class C motor.  The last time I
checked an Aerotech price list it was still in production and the retail
price was $13.95.  The delays were 5, 10 and 15 seconds. 

***********************************************************************
*   Robert (Bobby) Gormley        *     NOVAAR Section #205           * 
*  [email-masked] *     NAR #40847 / TRA #2113        * 
***********************************************************************

Article: 19783 of rec.models.rockets
From: [email-masked] (x )
Subject: Re: N2O / Propane Rocket
Date: 10 Oct 1995 06:11:41 GMT
Lines: 13
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In <[email-masked]> [email-masked] (William )
writes: 
>
>Shouldn't you be able to pressurize the Propane take with CO2 and get
>very similar characteristics to N2O?  Hmm.  Are liquid CO2 and N20
>mutually soluble?
>
>BillW

I've been pressurizing the propane with nitrogen, it works well.

Bob

Article: 19784 of rec.models.rockets
From: [email-masked] (kingrat)
Subject: How big are they today ?
Date: 10 Oct 1995 02:38:52 GMT
Lines: 11
Message-ID: <[email-masked]>

The largest motor I know of that's been flown in a high power rocket is 
an O 10000. I have heard of larger motors in development. Typically a 
'large' motor for high power is a K. K motors are 54mm diameter and about 
a foot long. Depends on the motor - some are bigger. I LCO'd a launch in 
London Ohio this past weekend and one of the fliers put up a 8 inch 
diameter rocket that was about 12 feet tall on a cluster of 3 K-500's. It 
was impressive...

Eric Specht
Tripoli 1755

Article: 19785 of rec.models.rockets
From: [email-masked] (Cottham1)
Subject: Re: N2O / Propane Rocket
Date: 10 Oct 1995 04:08:51 -0400
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]>

I've recently run a small N2O/alcohol motor, based on the Pc it was approx
11lbf for about 13-14secs.the chamber was made from acrylic so the
combustion can be seen clearly and a quite spectacular series of Mach
diamonds from the exhaust!, even if I say so myself ! B) The exhaust plume
was pretty much transparent except for the diamonds, which pleased me no
end !! the thrust was only half what I expected but the injector and the
chamber internal geometry both need more work to get the most out of them
so not to bad for a first firing!--eh!

Cheers Pete Cottham 

Article: 19786 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Igniting flashbulbs?
Date: 10 Oct 1995 07:23:26 GMT
Lines: 9
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
	<[email-masked]> <[email-masked]>
	<[email-masked]>

    ah, yes..  I had the choice of: A. Magicubes B. the Flip Flash at
    the store I dropped into.  I did realize before buying them that
    they were the mechanical type, so I got the other, only to find
    their need for a HV spark..

While the original flip-flash used a HV spark, I believe the more
common "flash bars" will work off normal voltages...

BillW

Article: 19787 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Igniting flashbulbs?
Date: 10 Oct 1995 08:26:49 GMT
Lines: 33
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, William
([email-masked]) says...
>
>    ah, yes..  I had the choice of: A. Magicubes B. the Flip Flash at
>    the store I dropped into.  I did realize before buying them that
>    they were the mechanical type, so I got the other, only to find
>    their need for a HV spark..
>
>While the original flip-flash used a HV spark, I believe the more
>common "flash bars" will work off normal voltages...
>

As owner of an SX-70, I can confirm this last -- the Flashbar (R) is 
fired by current direct from the 6V Polapulse (R) battery in the film 
pack -- current drawn in competition with the motors that flip the 
reflex mirror and drive the shutter circuits and light metering system, 
as well as (on newer models than mine) operating the sonar and focusing 
system.  AFAIK, there's not even a buffering capacitor to allow drawing 
more current than the battery can supply -- though this would be less 
needful with the Polapulse (R) battery, since it's designed to supply 
power in shortish, high-current pulses, and is replaced every tenth 
shot.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19788 of rec.models.rockets
From: [email-masked] (HankBop)
Subject: Re: Launch Report Questions
Date: 10 Oct 1995 04:14:42 -0400
Lines: 15
Message-ID: <[email-masked]>
References: <[email-masked]>

>>so my reports may not be too serious.  They will, however, be fun.<<

That's probably the most important aspect of this hobby -- FUN! 
I enjoy reading launch reports in this newsgroup, there's usually a lot of
good info to learn from. On those days when I'm stuck indoors yearning for
that big WHOOOSH in the sky, reading about rocket launches brighten my day
-- unless of course, the launch was a total disaster :-(. 
So post away, the funner the better...    
 
- Henry
"Not home, gone rocketing..."
NAR# 63923   TRA# 4012 
[email-masked]
[email-masked]

Article: 19789 of rec.models.rockets
From: Dennis Erwin Thurlow <[email-masked]>
Subject: Re: $2 million prize?
Date: 10 Oct 1995 11:28:43 GMT
Lines: 8
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

[email-masked] (The Silent Observer) wrote:
> As for advancing the space frontier today, building and flying a rocket 
> on an amateur budget (even one of comparable size to that needed for a 
> BD-10 homebuilt supersonic jet -- a cool $1 Million to build) that can 
With a little thought, I'm sure you could get supersonic for less.
People have put a $40,000 French built jet engine in a regular BD-5.
Cruise for 45 min. at 600+ mph.  You can even buy a used French jet
trainer based on the same engine for $200,000.

Article: 19790 of rec.models.rockets
From: [email-masked] (Doug Holverson)
Subject: Re: Thermalite
Message-ID: <99.307a5077@axolotl>
Date: 09 Oct 95 22:07:03 CST
Lines: 13

PH> I'm getting back into modeling again (just completed and flew a
PH> scratchbuilt C altitude the other weekend).  I started in 1958 and stopped
PH> in 1969.  One question -- just what is Thermalite? Is it the same as Jetex

Talk about BARs!:) (Born Again Rocketeers) Tell me about those early days
please because I missed them....

-DGH-

PS: Don't know anything about thermalite because I'm not a HPR guy (yet)....

Article: 19791 of rec.models.rockets
From: [email-masked] (LarryC)
Subject: Re: Jetex fuel comp, pt. II
Date: 10 Oct 1995 06:54:59 -0400
Lines: 27
Message-ID: <[email-masked]>
References: <[email-masked]>

Michael Edelman ([email-masked]) wrote:
> A while ago we had a brief discussion fo the composition of Jetex
> fuel. I have another data point. According to "Rocket Propulsion
> Elements", 3rd ed, by G. Sutton (Wiley & Sons, 1964)

> "Mixtures of ammonium nitrate and guanadine nitrate with appropriate 
> catylysts for decomposition are used for small rockets which propel
> small model aircraft. Loose powder is consolidated nder high pressure
> (perhaps 7000 lb per sq in.) into suitible molds. The finished charge 
> is hard and rock-like in appearance."

> I wonder what the catalyst is?  I suspect a metal oxide, but I don't
> have any further evidence. What color is pure guanidine nitrate?

> It does sound like it would be simple enough to make pellets with my 
> benchtop arbor press. 

> --mike

The catalyst is ammonium dichromate. It's the traditional catalyst, and 
it accounts for the abundant slag. Also, from the color of the flame, 
there is a small amount of KNO3 in the mixture. This improves the burning 
rate and stabilizes the NH4NO3 from crystal transition, which would 
otherwise deform the pellet during storage.

-Larry Curcio

Article: 19792 of rec.models.rockets
From: [email-masked] (al jackson)
Subject: Re: N2O / Propane Rocket
Date: Tue, 10 Oct 1995 08:39:59
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]> [email-masked] (LRocket) writes:
>From: [email-masked] (LRocket)
>Subject: Re: N2O / Propane Rocket
>Date: 9 Oct 1995 02:43:24 -0400

>I have built and fired a 700 lbf thrust LOX/propane engine which I found
>to have extremely good performance. I measured C* efficiencies in the mid
>to high nineties (perhaps a first for amatuer rocketry).  As any decent
>atomization/vaporization model will tell you, propane is very easy to
>burn.  If you have a decent mixing injector, you can't go wrong - as far
>as performance is concerned.  But, also as predicted, throat erosion rate
>is very high, unless a fair amount of propane is used as a film coolant.

>BTW I agree that ethylene or, preferably, ethane are desireable for their 
>similar vapor pressures to N2O, but they are more difficult and expensive
>to get ahold of, and one two phase liquid in a bipropellant rocket engine
>is trouble enough!

>Tom Mueller

Hmmm... I was told ethylene (dont know about ethane) was not that
hard or expensive to get hold of. And that it was a very safe
substance to handle. But I never did find out the price. Anybody
know?

al

Article: 19793 of rec.models.rockets
Subject: Re: Plugging booster motors
Message-ID: <[email-masked]>
From: [email-masked] (Mark Johnson)
Date: Tue, 10 Oct 1995 08:14:17
References: <[email-masked]>
Lines: 18

In article <[email-masked]> [email-masked]  (Kevin Forsyth) writes:

>Is it possible and safe to plug black powder booster motors with 30-min epoxy
>to make -P's out of -0's?

Possible - Yes.
Safe - Debatable. Most would say "probably."
Legal - Nyet. 

"Legal" being in the context of the Model Rocket Safety Code, which says you 
will use model rocket motors without modification. Since the Code is part of 
the NFPA Code, adopted by nearly every state in one form or another, modifying 
a motor probably *is* illegal...
===========
Mark Johnson                       USnail: Symbios Logic, Inc
E-mail:  [email-masked]          OEM RAID Business Team
Voice: (316) 636-8189 [V+654-8189]         3718 N. Rock Rd.
Visit our web page: http://www.symbios.com Wichita, KS  67226

Article: 19794 of rec.models.rockets
From: [email-masked] (nal040700-Mckiou)
Subject: Re: US Spacemodeling Team Selection Results
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
Date: Tue, 10 Oct 1995 17:59:23 GMT
Lines: 77

In article <[email-masked]>,
 <[email-masked]> wrote:
>In article <[email-masked]>, [email-masked] (nal040700-Mckiou) writes:
>> S8E (E-Radio Controlled Rocket Glide)
>> 1. Kevin McKiou
>> 2. Herb Semmelmeyer (sp?)
>> 3. George Gassaway
>
>Well there must be a story here. What happened to Ben and George in S8E?

They both maxed the first round.  In the second round, George Riebesehl
missed the max by about 15 sec.  Ben Roberto's receiver died after the
first round and he had to go to his backup model which was not
trimmed very well.  He did not get a particularly good boost
in the second round and did not max.  I do not know his time.  The
second round was tough on a number of people.  I think George G,
Herb and I were the only one's to max it.  But, I could be wrong.
Anyhow, in the third round George R. launched just after me and after
about 5 sec I heard Bernie Biales (who was standing next to me) say
"Oh Noooo.."  I was not able to look, but apparently George R's model
appeared to literally explode about 2/3 of the way through the
boost.  Bernie said it was the worst shred he had ever seen.  I saw
a few of the pieces.  The pod, boom and tail were all still
in one piece.  The wings apparently flutted and ripped apart near
the root.  At least one outer wing panel was undamaged.

In the flyoff round I flew very conservatively.  I managed to get
in the air first only because Herb had a misfire.  Actually I *think*
Dr. Bob Kreutz (the LCO) pointed at both of us and said "Dual Launch"
but I wasn't real sure and since I felt that Herb's hand moved
first, I let him light-up first.  Once we were in the air it was
apparent that I had altitude and time on him.  So, the best thing
to do probably would have been to shadow him.  I knew that I also had
a better sink rate...but Herb is much more experienced and having flown
in lots of AMA and F3B competition, he did the only thing he could
do.  He flew downwind into the strongest lift and let his model
drift with it.  He kept the nose pointed into the wind and would
occasionally pull up the nose to be able to see its orientation.  I knew
better than to try and fly with a more experience pilot downwind
(been downwind, lost control and crashed a couple of times, never
felt the urge to repeat that mistake).  Anyhow, I just hung the plane
in the best available air (over a pylon racing runway) and flew at 
minimum sink.  George and Ben were timing me and continually
advising me of Herb's status.  Apparently he flew brilliantly.
George said his model was nothing but a dot downwind.  In the end
Herb decided to come up wind a bit (don't know why.  Phil said they
thought I was sky'd-out in lift).  That was all it took.  He landed
before I did and I won.  My time was just over 8 minutes.  I think
Herb had a time ~7:45.  Things worked out for me and I must give
credit to Ben and George for continually advising me, telling me to 
"stay-put".

I'm not sure what happened to George Gassaway in that last round.
He went up after Herb and according to Ben and George he tried to
fly downwind like Herb.  Apparently he had trouble keeping his
model under control and landed quite a bit before Herb.

Oh...to answer the question about what kind of models we were flying,
they were all pretty much conventional S8e rocket boosted RC sailplanes.
George G
was flying a Big Dark-Star model (~250 sq in wing).  Herb was flying
a composite Badger (Phil Barnes design - Wing on top, Pod in
middle, boom on bottom - like many Europeans fly - about 200 sq in).
I was flying my StingRay 3.  It has a 206 sq. in.  parabolic curved wing 
(no dihedral joints), servos inside the wing root and a
bullet-shaped pod on a boom in front of the wing.  All three models
had inverted V-tails. 

That's about it.

One more thing.  If you are interested in these kinds of rocket
gliders, drop me a note.  I have done a LOT of research and had
wonderful mentors in Bob Parks, George Riebesehl and Ben Roberto. I
would be happy to share information and provide plans and advice.

Kevin McKiou

Article: 19795 of rec.models.rockets
From: [email-masked] (Tommy Usher)
Subject: Launch Report, Birmingham, AL
Date: 10 Oct 1995 13:59:29 GMT
Lines: 34
Message-ID: <[email-masked]>

Well, I am not sure what format this is supposed to follow, but I figure
you might get a chuckle out of this.  I recently entered the hobby (I had
kicked the idea around for years, and finally took the leap when I found
a starter set on clearance at Walmart.) and this was my second effort at
launching my first rocket.  The first attempt went quite well.  The rocket
launched, and was recovered.  The second time, my daughter and I went to a 
local park and set up.  We determined what direction the wind was blowing
(very light wind, but I wanted to insure that the rocket would come down in
the open area) and then we started launching.  First launch, I used an A
class engine.  Nice flight, easy recovery.  Second launch, I used a B class
engine.  Much better altitude, easy recovery.  Third launch, I used a C
class engine.  Man, that thing took off, and achieved an incredible (at least
to me) altitude.  I actually lost sight of the rocket, but I saw the chute
deploy.  Then I knew something was wrong.  I could see the chute, and I could
see the rocket, but clearly the chute and the rocket were taking different
paths.  I stood there, watching the rocket dropping rather quickly, the
recovery wadding floating about, and the chute moving along a pretty good
clip.  The rocket body, sans nose cone, was recovered intact, and will no 
doubt fly again, but the parachute, and nose cone drifted out of sight.  I
don't know if the shock cord came loose (it seemed secure when I checked 
it), burnt through somehow (I loaded three sheets of recovery wadding as the
instructions said.), or broke under some stress (stronger upper level winds?),
or what....

In any case, an interesting experience.  I am looking forward to building
both a payload carrying rocket, and a multi-stage.  I may also invest in
an Astro-Cam, but I would hate to have been flying one yesterday....

-- 
+----------------------------------------------------------------------------+
| Tommy Usher  No Frills Software | Lubarsky's Law of Cybernetic Entomology: |
| [email-masked]             | There's always one more bug.             |
+----------------------------------------------------------------------------+

Article: 19796 of rec.models.rockets
From: "John P. Petrakis" <[email-masked]>
Subject: airfoiling fins
Date: 10 Oct 1995 15:22:46 GMT
Lines: 6
Message-ID: <[email-masked]>

What do most folks do when airfoiling 5-ply 1/8 inch plywood?
I assume few people out there have the patience to put a full
circular arc supersonic airfoil over the entire surface.  What is
the most favored practice when it comes to this?  Leading and
trailing edges sharp, rounded or what?

Article: 19797 of rec.models.rockets
From: [email-masked] (Matthew S Greenlaw)
Subject: Confirmed at 14 years?
Date: 10 Oct 95 15:17:36 GMT
Lines: 4
Message-ID: <mgreenl.813338256@hubcap>

I got confirmed to fly class B motors at only 14 years old.
I heard someone say you had to be 18--is this true? I have flown
lots of class B motors, even clusters of class B. Thanx.

Article: 19798 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: $2 million prize?
Date: 10 Oct 1995 17:46:35 GMT
Lines: 37
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, Dennis Erwin Thurlow 
([email-masked]) says...
>
>[email-masked] (The Silent Observer) wrote:
>> As for advancing the space frontier today, building and flying a 
rocket 
>> on an amateur budget (even one of comparable size to that needed for 
a 
>> BD-10 homebuilt supersonic jet -- a cool $1 Million to build) that 
can 
>With a little thought, I'm sure you could get supersonic for less.
>People have put a $40,000 French built jet engine in a regular BD-5.
>Cruise for 45 min. at 600+ mph.  You can even buy a used French jet
>trainer based on the same engine for $200,000.

Indeed -- come to that, you can buy a used Mig for around $1 million, 
and you can buy a Pegasus orbital launch for not too much over $2 
million, too -- but the point is to build it yourself.  A BD-5J is 
already on the edge without flutter testing the airframe on every flight 
-- the BD-10 is designed as a supersonic airplane from the get-go, and 
still a homebuilt (if Jim Bede every gets the kits out the door).

The point here is amateur-built, not demilitarized.  I don't see any 
reason the prize parameters couldn't be acheived with a large 
amateur-built liquid rocket -- as I said before, this is comparable to 
Sheppard's first suborbital flight on a Redstone, but with less payload.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19799 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: N2O / Propane Rocket
Date: 10 Oct 1995 17:37:58 GMT
Lines: 45
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, al jackson 
([email-masked]) says...
>
>In article <[email-masked]> [email-masked] (LRocket) 
writes:
>>BTW I agree that ethylene or, preferably, ethane are desireable for 
their 
>>
>>similar vapor pressures to N2O, but they are more difficult and 
expensive
>>to get ahold of, and one two phase liquid in a bipropellant rocket 
engine
>>is trouble enough!
>
>>Tom Mueller
>

Can you explain what causes the problem, and what constitues a "two 
phase liquid" in this context?  Does this have something to do with the 
propellant being partly vaporized by presure drop through the injector, 
or is it another factor of some kind?

>
>Hmmm... I was told ethylene (dont know about ethane) was not that
>hard or expensive to get hold of. And that it was a very safe
>substance to handle. But I never did find out the price. Anybody
>know?
>

Ethylene is cheap enough to be used commercially to ripen fruit after 
harvest and green shipping -- but that application doesn't need much of 
it.  It's probably more expensive than propane, but I'd be suprised if 
it was more than four or five times the price -- which would still make 
it comparable to N2O.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19800 of rec.models.rockets
From: [email-masked]  (Kevin Forsyth)
Subject: A brief launch report, questions & comments
Date: Tue, 10 Oct 1995  11:36 EDT
Lines: 41
Message-ID: <[email-masked]>

Recently back into rocketry actively after a 15-year hiatus, I'm slowly 
working my way up to the fun-sized motors, the kind they never had when I was
young.  Got talked into buying my first composite motor yesterday, in 
anticipation of completing my Estes Terries/Sandhawk with staging conversion.
It's an Aerotech E15-7 and I can't wait until I have a finished rocket that 
can use it.
 
Question:  will my home-built 12v ignition system running two fresh 6v
lantern batteries be enough to ignite the copperhead, or do I have to upgrade
(again) to a motorcycle battery or some such?

Sunday I launched for the first time my Estes Rascal.  I bought it because it
was cheap, and it completes my "Big-Bertha-style" collection: a Bertha, an 
Astron Ranger (a Bertha with a 3-motor cluster and payload, which I omitted), 
and now the squat Rascal.  I modified the Rascal to carry a 24mm x 89mm motor 
(the Estes E-15, yikes!) and flew it twice Sunday with D12-3's.  Both flights 
were perfect, but each time the (enamel) paint at the top of the tube was 
scorched, as if the gasses on ejection were blown backward from the nose, 
still hot.  The streamer and cone were unharmed.  Is this a hazard of using 
big motors in a body tube that's only 7 inches long?  Is there a good way to 
prevent it?  Should I not risk the E15 in it?  :)

Wanted to comment on two items I've been using in my rockets which I like a 
lot.  One is silver mylar sheet, the kind of stuff they use in greenhouses 
(and party balloons).  Works great for streamers, very shiny and noisy... 
once I even lost track of a rocket coming down but spotted it again because I
could hear the streamer crackling.
 
The other thing is a bit stranger... ever since I was a young kid I have 
noticed these strips of metal lying in the street.  I think they might be
part of the pavement that pops loose, I seem to find them most often in the 
gutter on older, beat-up roads.  Anyway, they're about 1/8" wide and usually 
6" long, and they're every bit as stiff as Estes engine hooks.  I clean them 
up with sandpaper and bend them with pliers, and make my own hooks.  BTW, 
anyone know what these things really are?
 
Seven rockets built since August and 4 in work?  No, I'm not obsessed.  ;)
 
/kevin

Article: 19801 of rec.models.rockets
From: [email-masked] (Mark Bundick)
Subject: RMR Political? (was Re: Launch Report Questions)
Date: 10 Oct 1995 12:05:16 -0500
Lines: 18
Message-ID: <199510101704.MAA00800@cybl35>

[email-masked] (The Silent Observer) wrote:

> The only people taking things too seriously here are the NAR and TRA 

> politicians -- and some of us, at least, just ignore those threads.  I 

> >never< ignore a launch report...  B)

Hey!  Have I been THAT heavy handed?  I mean, seriously, when was the
last time there was a POLITICAL dogfight here???  And I read the launch
reports, too!

(whimper, whipmer......)

======================================================================
Mark B. Bundick                "Running a NARAM will never be harder 

NAR President                   than licking your political wounds. "

Article: 19802 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: RMR Political? (was Re: Launch Report Questions)
Date: 10 Oct 1995 18:01:08 GMT
Lines: 32
Message-ID: <[email-masked]>
References: <199510101704.MAA00800@cybl35>

In article <199510101704.MAA00800@cybl35>, Mark Bundick ([email-masked]) 
says...
>
>[email-masked] (The Silent Observer) wrote:
>
>> The only people taking things too seriously here are the NAR and TRA 
>
>> politicians -- and some of us, at least, just ignore those threads.
I 
>
>> >never< ignore a launch report...  B)
>
>Hey!  Have I been THAT heavy handed?  I mean, seriously, when was the
>last time there was a POLITICAL dogfight here???  And I read the launch 
 
>reports, too!
>
>(whimper, whipmer......)
>

I wasn't talking about you, O Gweat Wabbit...  B)

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19803 of rec.models.rockets
From: [email-masked] (Mark Bundick)
Subject: Re: $2 million prize?
Date: 10 Oct 1995 11:45:54 -0500
Lines: 16
Message-ID: <199510101644.LAA00758@cybl35>

[email-masked] (The Silent Observer) wrote:

> Or wouldn't you consider the possibility of Microsoft or Motorola 

> contracting out the design and construction of the rocket fleet they'll 

> need for their orbital phone networks, rather than having to buy the 

> launches from the government, an advance?

I thought Motorola HAD contracted with Arianespace, Lockheed Martin and
the Russians to launch their network of Iridium satellites???

=========================================================
Mark B. Bundick        "Running a NARAM will never be more
NAR President           fun than Shuttle launches at dawn."

Article: 19804 of rec.models.rockets
From: [email-masked] (Mark Bundick)
Subject: Glider Trimming (was Re: Design Book)
Date: 10 Oct 1995 12:19:00 -0500
Lines: 25
Message-ID: <199510101718.MAA00819@cybl35>

"Bullet" Bob Kaplow ([email-masked]) wrote

> The ONLY way to accurately place the CG is to compute the "neutral point" 

> (the BG equivalent of the CP, in fact the equations for fins and wings 

> match), decide on a stability margin (% of wing chord, usually about 20% 

> for free flight models)

While the stated procedure is correct, the margin's a bit hefty.  Most world
class free flight models run 10% or less.  I generally don't run below that,
but at 10% there's sufficent stability to work without being terribly tricky
to trim.  I suggest dedicated competitors try a static margin, hand launch or
fly the bird, then see how they like the performance vs. ease of trim results
and then either widen or reduce their margin on the next flight or design.

And while I appreciate the attribution as a glider teacher, I frankly can't
remember giving you any lessons.  You'll have to refresh my memory at the
club launch next week....

=======================================================================
Mark B. Bundick                 "Running a NARAM will never be as 

NAR President                    much fun as flying gliders"

Article: 19805 of rec.models.rockets
From: [email-masked] (Onnie X. Granados)
Subject: Re: Fin Drag
Date: 10 Oct 1995 19:56:01 GMT
Lines: 67
Message-ID: <[email-masked]>
References: <[email-masked]>

JABeecher ([email-masked]) wrote:

: I designed a glider/rocket which breals apart in mid-air.  When in boost
: configuration, it looks a little like one of theose outlawed lawn darts,
: sort of four-winged delta shape.
: Sadly, it will spins on the y-axis (somersaults) on every launch.

: I think it might be because there is too much drag at the front of the
: rocket, and was thinking of adding a front length of body tube to help
: stablize it, but I am actually unsure what the problem might be.  Any

	Hi.  Somebody else already mentioned that you're probably looking 
at a Center of Pressure/Center of Gravity problem.  And if your local 
library or bookstore has a copy of G. Harry Stine's "Model Rocketry 
Handbook," GO GET IT NOW!!!  It's great, and it'll explain things pretty 
well.

	But as for a "quick and dirty" approach -- there's a good old 
"spin" test you can do that'll give you a good indication as to how your 
rocket will perform in flight.  How to do:

	Tie a string around the rocket at the *exact* center of gravity.
That is, tie a string, a *long* string (at least ten feet) to the rocket 
at the point where, if it's just hanging by the string, it balances front 
and back.  Depending on how your rocket is designed, this may be tricky, 
but I'm sure you'll figure out something! :-)  And MAKE SURE YOU DO THIS 
WITH A FULL ROCKET MOTOR IN THE ROCKET!  Very important.

	And tape the string in place once you find the right point, so it 
won't slip.

	Then, go out in the yard, in a parking lot, *anywhere* you've got 
some space ... and start twirling the rocket around, like a lasso.  Make 
sense?  That is, spin it over your head, gradually letting out string as 
the rocket gains momentum.  Yee haw!!!  With any luck, it'll go flying 
in a circle around you, nose forward.

	Let it out a few feet, so you can see it's motion.  If you built 
it correctly, it will fly nose first, parallel to the ground, and look 
pretty stable, not moving side to side.

	But if your CP is ahead of your CG, the rocket will be unstable 
-- it may fly sideways, tail first, whatever.  Not a pretty sight.

	If it's behaving like that, there are two things you can do -- 
change the CG forward by adding weight to the nose, or bring the CP 
backwards by making the fins bigger.  It's usually easier to start by 
adding a little weight to the nose.  But do what you will.

	Then, once you've done that, give it the ol' spin test again.
With any luck, within a short time that ol' rocket will be flying 
perfectly, nice and level and stable.

	That's it!  Once you're at that point, you can be pretty certain 
that at the very least it'll fly nose first, in a fairly straight line.

	Good luck!  And let us know how things turn out!

							Oz

------------------------------------------------------------------------------
 Onnie Granados                |                    email: [email-masked]
 Technology Services &         |                        phone: (206) 296-6216
 Computer Lab Coordinator      | WWW:http://www.seattleu.edu/~onnie/home.html
     
             Bonum est praestolari cum silentio salutare Dei

Article: 19806 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: $2 million prize?
Date: 10 Oct 1995 17:47:38 GMT
Lines: 33
Message-ID: <[email-masked]>
References: <199510101644.LAA00758@cybl35>

In article <199510101644.LAA00758@cybl35>, Mark Bundick ([email-masked]) 
says...
>
>[email-masked] (The Silent Observer) wrote:
>
>> Or wouldn't you consider the possibility of Microsoft or Motorola 
>
>> contracting out the design and construction of the rocket fleet 
they'll 
>
>> need for their orbital phone networks, rather than having to buy the 
>
>> launches from the government, an advance?
>
>I thought Motorola HAD contracted with Arianespace, Lockheed Martin and 
 
>the Russians to launch their network of Iridium satellites???
>

I wouldn't know -- they very well might have.  I was referring to the 
concept as an advance, rather than attempting to claim that a particular 
example might go that way.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19807 of rec.models.rockets
From: [email-masked] (Paul Ross Milner)
Subject: forign manufacts
Message-ID: <[email-masked]>
Date: Tue, 10 Oct 1995 18:18:02 GMT
Lines: 5

Does anyone know if there are model rocket manufacturers in other 
countries? If so, who are they and what are their addresses?
--
"Non illegitimi te carborundum"

Article: 19808 of rec.models.rockets
From: [email-masked] (March A. Briner)
Subject: Re: G125? and Whatever happened to...
Date: 10 Oct 1995 12:08:59 -0400
Lines: 40
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> [email-masked] (Jason L. Eckhardt) writes:
>I've recently got myself back into rocketry. My favorite models 5-7 years
>ago were Estes Red Max, Estes Maxi-Icarus, and Estes Goblin. I've been to
>every hobby shop
>and I don't see any of these anymore. Does Estes still make these?

Probably not. Though, depending on how much you are willing to spend, 
some hobby shops carry such models...

>Anybody out there built any estes replicas in the mid- or high-power 
>variety? 

There are a few kits like that. Original Rockets makes a 4" diameter Blue 
Max (very similar to a scaled-up Red Max of the same size). NCR makes (or 
used to make, not sure if they still do) an 8" diameter version of the 
Goblin called Hobgoblin. 

>On a different note, I recently built a loc ezi-65 and I would like to test
>fly it with the least power. They mention a G125 on the spec sheet as the 
>smallest engine, but I've not been able to find one. The closest thing I've
>seen is G104 (Aerotech RMS). Where do I find G125? Or would G104 be sufficient?

A G104 will loft it up about 400 or 500 feet. It wouldn't be 
underpowered, but it wouldn't be a very long-lived flight, either. 

Kevin Nolan at Countdown Hobbies has G125s to sell (he usually did when I 
needed one). Give him a call if you want to try a flight with a G125. 

Another motors you can use for 1st flight is a G80-4 (Aerotech). This 
will get you up to about 500 to 600 feet. Good luck...

******************************************************************************

	Marc Briner		    *		nin    ei nc hn    ail
   Plymouth State College	    *		sn in  ei nc hn  ai ls
       New Hampshire		    *		ni  ne in ch na il  sn
   Live, Freeze, and DIE!	    *		in    ein ch nai    ls

******************************************************************************

Article: 19809 of rec.models.rockets
From: [email-masked]
Subject: First Wac Corporal Flight 50 Years Ago 10/11/45
Date: 10 Oct 1995 21:28:46 GMT
Lines: 36
Message-ID: <[email-masked]>

                       Texas Rocket Grandmaster 
                          by  Al Jackson
 
    I travel  from  Houston  to  Austin  by  highway  290  fairly often, and
sometimes I stop at Brenham Texas for  lunch. I skip the fast food joints on
290 and go downtown.  It  is  a  beautiful  small  town  with a charming old
downtown (founded in 1844). Only recently  have I become aware that a native
Texan from Brenham fulfilled  a  dream  started  by Robert Goddard, in fact
doing in 10 months what Goddard had striven for years to accomplish. Even
more than that he was co-founder of the Jet Propulsion Laboratory, JPL, and
co-founder of Aerojet General. By 1945  he  had eclipsed Goddard as the most
important American rocket scientist. He  was  a consummate researcher in the
theoretical engineering of rocketry and  a  master manager of several rocket
and rocket vehicle projects  forthe U.S.Army.  So who was this Texas
pioneer 'Wernher von Braun'? He is Dr. Frank J Malina from Brenham Texas.
    Malina was the originator and leader  of a project that has an important
anniversary on October 11 this year. It  will be the 50th anniversary of the
first full up launch of  a  Wac-Corporal  sounding rocket. We tend to forget
that Goddard had a solid scientific use for his development of rockets, that
was to sound the upper atmosphere. We all love Goddard for his inventiveness
in rocket hardware and  his  stubborn  individualism,  and given time he may
have realized his sounding rocket  dream.  However while he struggled in the
New Mexico desert in 1936  Frank  Malina  ,  still a graduate student at Cal
Tech, had put on the wall of his office a chart of how a successful sounding
rocket project might be accomplished.  Unlike Goddard he recognized the need
for a team and a choice of team captains.
    Malina's dream was interrupted by  World  War  II. Along with his mentor
Theodore von Karman (the great  20th century aerodynamicist) he directed the
development of  Jet Assisted Take Off,  JATO, rockets for use by the Army
Air Force. This work for the  U.S.  Army  lead  to the formation of JPL, and
when von Karman moved the Pentagon ,as  a consultant,Malina became the first
director of JPL. There is a  straight  line heritage from these solid rocket
motors to the intercontinental missiles  in the American defense arsenal and
even up to the current Space Shuttle booster motors. His involvement in this
project alone is enough to have made him a famous rocketeer.
    In 1944 Dr. Malina was  sent  to  England and France to inspect salvaged

Article: 19810 of rec.models.rockets
From: [email-masked] (Bob Martino)
Subject: New www Astro Site
Date: Tue, 10 Oct 1995 15:37:09 -0400
Lines: 21
Message-ID: <[email-masked]>

A new www site related to astronomy has just come online.

                       PERKINS OBSERVATORY

Once housing the 3rd largest telescope in the world, Perkins Observatory is
located in Central Ohio just North of Columbus.  We have many public
programs and other services, including meetings of the Columbus
Astronomical Society and a guest lecture series with astronomy professors
from Ohio Wesleyan University and the Ohio State University.  Families,
individuals, and groups of all  sorts are welcome!  For more information
point your web browser to:

       http://www-astronomy.mps.ohio-state.edu/~perkins/

-- 
Bob Martino                         "Science like nature, 
[email-masked]   must also be tamed,
                                     with a view toward its preservation"
My opinions, no one else's                               -Rush

Article: 19811 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Launch Report, Birmingham, AL
Date: 10 Oct 1995 17:59:55 GMT
Lines: 56
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, Tommy Usher 
([email-masked]) says...
>
>Third launch, I used a C
>class engine.  Man, that thing took off, and achieved an incredible (at 
least
>to me) altitude.  I actually lost sight of the rocket, but I saw the 
chute
>deploy.  Then I knew something was wrong.  I could see the chute, and I 
could
>see the rocket, but clearly the chute and the rocket were taking 
different
>paths.  I stood there, watching the rocket dropping rather quickly, the
>recovery wadding floating about, and the chute moving along a pretty 
good
>clip.  The rocket body, sans nose cone, was recovered intact, and will 
no 
>doubt fly again, but the parachute, and nose cone drifted out of sight. 

There are three likely possibilities for the cause of this accident.
First, you may have used an engine with a too-short delay (for that 
particular combination of thrust, impulse, and rockets, anyway); this 
would cause ejection to occur before apogee, at a much higher velocity 
that is desirable, possibly overstressing the shock cord and causing a 
separation.  This can also cause "zipper" damage to the tube, and "Estes 
dents" when the nose cone snaps back and slams into the body tube.

Second possibility is, as you surmised, a burnt shock cord.  While I'd 
have pooh-poohed that idea 20 years ago, at least for a rocket on only 
its fourth flight, Estes is apparently using much less robust shock 
cords than they used to -- and making them too short, into the bargain.

The third possiblity relates to the too-short Estes stock shock cords -- 
which also contribute to "Estes dents".  If the ejection charge in the 
motor was on the hot side, a too-short shock cord might part when the 
nose cone came to the end of its leash at higher velocity than on 
previous flights; this might have been happening gradually through the 
previous three flights, unnoticed during ground inspections, and taken 
its final turn on the C-engine flight.

I'd suggest using a longer (approximately three times body length) and 
more robust (something like twice the weight of the original) shock cord 
for a replacement.  I'd also suggest thinking about whether the 
parachute might have ejected early, and if you think it did, try the 
next longer delay on the next C flight.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19812 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: Igniting flashbulbs?
Date: 10 Oct 1995 18:20:45 GMT
Lines: 25
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

Jon Pike ([email-masked]) wrote:

[flashbulb discussion ...]

: 	Other questions, for my research project...  does the Thermalite
: get ignited from contacting the hot glass of the bulb, or just from heat 
: soaked up from the flash?  (i.e. do I need to attach it to the bulb, or 
: just have it very close?)  Are there different kinds of flashbulb? I seem 
: to have bought some (GE Flip Flash) that don't have any resistance across 
: their leads, (?!?)  what are some sources  (and names) of types that have a 
: filament?

Tape the Thermalite directly to the flashbulb.  A wrap of Scotch tape works
well. Have the Thermalite run the length of the bulb for maximum contact.

Some "Flip Flash" bulbs are not conventionally ignited, as well as the 
"Magicubes".  Polaroid 600 flashbars work, but you may find it difficult
to find them.  I bought some two years ago at Walmart, but our store no
longer carries them.  Robby's Rockets sells AG-1B bulbs, prewired. Adept
Rocketry, and probably others, carry Robby's products, or you can get
them directly from him.  He's in the FAQ Mfg.'s List.
--
Lee Reep 
 [email-masked] 

Article: 19813 of rec.models.rockets
From: [email-masked] (Jane Marie Culver)
Subject: Re: A brief launch report, questions & comments
Date: 10 Oct 1995 21:41:13 GMT
Lines: 16
Message-ID: <[email-masked]>
References: <[email-masked]>

Kevin Forsyth ([email-masked]) wrote:
:
:
:
: The other thing is a bit stranger... ever since I was a young kid I have 
: noticed these strips of metal lying in the street.  I think they might be
: part of the pavement that pops loose, I seem to find them most often in the 
: gutter on older, beat-up roads.  Anyway, they're about 1/8" wide and usually 
: 6" long, and they're every bit as stiff as Estes engine hooks.  I clean them 
: up with sandpaper and bend them with pliers, and make my own hooks.  BTW, 
: anyone know what these things really are?

I remember those things too!  I can remember picking them out of the streets
20 years ago in Milwaukee, WI.  Wonder what they are?

Article: 19814 of rec.models.rockets
From: Larry Klug <[email-masked]>
Subject: Re: Iron-on covering
Date: 10 Oct 1995 21:20:54 GMT
Lines: 31
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

[email-masked] (Iskandar Taib) wrote:

>Umm.. I don't think any paints do this. Most lose weight as the
>solvents leave. Some do polymerize when exposed to air, and may indeed
>absorb some oxygen, but I doubt its very much..

Iskandar,

This process was explained to me by my father who is a former research
chemist for Hercules, Inc. specializing in cellulose and polymers.  He 
said that paint does gain weight when it dries because solvent molecules 
are replaced by chains of oxygen molecules.  And heck, he's my dad, he 
wouldn't lie about this, what does he have to gain?

According to the RC people, dope and tissue is old technology that 
really doesn't add much strength compared to a an iron-on covering.

I have used dope and tissue in the past for light BGs, but now that I'm 
doing far heavier RC models, I just can't see the point.  Iron on 
covering is really easy and produces really excellent results.

BTW, my Stratoblaster is in great shape and ready to launch with my 
recently narrow banded futaba gear.  My modified flagship is awaiting 
micro servos and final assembly - both models completely covered with 
blue and silver Flitecoat.

Larry Klug
(Aspiring RC BG pilot in argument with Iskandar on the net)

Article: 19815 of rec.models.rockets
From: [email-masked] (Jeffrey A. Pleimling)
Subject: Anyone with Estes nose cone information?
Date: Tue, 10 Oct 95 16:15:28 GMT
Lines: 17
Message-ID: <[email-masked]>

I've been trying to re-create some of my favorite, old Estes
designs but have run into a problem - I don't know what their
nose cone item number mean.  I know that a BNC-20N fits a BT-20,
but what shape and length?

I know that BMC has replicas of *some* Estes nose cones, but
they don't have every one.  With the right information, they
can make them, however.

Can anyone help? Thanks.

Jeff
--
Jeffrey A. Pleimling | [email-masked]
In Time, all things come to pass;
The Neglected become Loved, The Loved become Hated,       -Arthur Samuel Hyun
And the heroes feel the cold grip of death around their throats...

Article: 19816 of rec.models.rockets
From: [email-masked]
Subject: A Important Rocket Anniversary
Date: 10 Oct 1995 21:23:08 GMT
Lines: 85
Message-ID: <[email-masked]>

                       Texas Rocket Grandmaster 
                          by  Al Jackson
 
    I travel  from  Houston  to  Austin  by  highway  290  fairly often, and
sometimes I stop at Brenham Texas for  lunch. I skip the fast food joints on
290 and go downtown.  It  is  a  beautiful  small  town  with a charming old
downtown (founded in 1844). Only recently  have I become aware that a native
Texan from Brenham fulfilled  a  dream  started  by Robert Goddard, in fact
doing in 10 months what Goddard had striven for years to accomplish. Even
more than that he was co-founder of the Jet Propulsion Laboratory, JPL, and
co-founder of Aerojet General. By 1945  he  had eclipsed Goddard as the most
important American rocket scientist. He  was  a consummate researcher in the
theoretical engineering of rocketry and  a  master manager of several rocket
and rocket vehicle projects  forthe U.S.Army.    So who was the Texas
pioneer 'Wernher von Braun'? He is Dr. Frank J Malina from Brenham Texas.
    Malina was the originator and leader  of a project that has an important
anniversary on October 11 this year. It  will be the 50th anniversary of the
first full up launch of  a  Wac-Corporal  sounding rocket. We tend to forget
that Goddard had a solid scientific use for his development of rockets, that
was to sound the upper atmosphere. We all love Goddard for his inventiveness
in rocket hardware and  his  stubborn  individualism,  and given time he may
have realized his sounding rocket  dream.  However while he struggled in the
New Mexico desert in 1936  Frank  Malina  ,  still a graduate student at Cal
Tech, had put on the wall of his office a chart of how a successful sounding
rocket project might be accomplished.  Unlike Goddard he recognized the need
for a team and a choice of team captains.
    Malina's dream was interrupted by  World  War  II. Along with his mentor
Theodore von Karman (the great  20th century aerodynamicist) he directed the
development of  Jet Assisted Take Off,  JATO, rockets for use by the Army
Air Force. This work for the  U.S.  Army  lead  to the formation of JPL, and
when von Karman moved the Pentagon ,as  a consultant,Malina became the first
director of JPL. There is a  straight  line heritage from these solid rocket
motors to the intercontinental missiles  in the American defense arsenal and
even up to the current Space Shuttle booster motors. His involvement in this
project alone is enough to have made him a famous rocketeer.
    In 1944 Dr. Malina was  sent  to  England and France to inspect salvaged
V2s and V1 launch sites. Returning by  plane over the Atlantic he decided to
ask the Army ordnance Department to  fund his cherished goal of building and
launching a vehicle to sound the  upper atmosphere in regions that could not
be reached by balloons.  This  was  December  of  1944. From designs by H.S.
Tsien and Malina, he  and  Homer  Stewart  submitted  and  got approval on a
proposal to launch a sounding rocket with a 25 lb payload to 100,000 ft.
    There had already been a  program  started  at  the newly founded JPL to
build military rockets. Malina organized  a team to use components developed
from this program. It is amazing  that  the Von Karman-Malina program at JPL
during WWII accomplished ,  on  a  smaller  scale, almost the same technical
objectives as von Braun's  huge  V2  project.  A  viable liquid rocket motor
using nitric acid and aniline with 1500  lbs of thrust was developed and the
Private-series of missiles. The main  difference  being the V2's much larger
rocket motor  and  especially  its  guidance system a technology still being
researched at JPL by the end of the War.
    Once the project  was  approved  Malnia  and  his  JPL  crew turned over
several ideas for the sounding rocket.  It  turned out that the solid rocket
motors would be too heavy  for  the  flight.  They  needed a long burn light
weight rocket. So a liquid motor  powered  vehicle boosted quickly to a high
speed was decided upon. They  needed  the  initial  boost in order to gain a
sufficient amount of stability from the  vehicle  fins since they had yet to
developed an active onboard guidance system. The booster system used some of
the solid  rocket  technology  from the JATO  units  that  JPL  had already
fashioned. The booster and 2nd stage liquid rocket were to be launched using
a 60 ft tower.
    In July of 1945 the  flight  characteristics  of the booster were tested
with a 1/5 scale model at  Goldstone  Lake, California. The tests showed the
viability of the solid booster  system  and a three fin stabilization system
rather than four  fins  favored  by  ordnance  experts.  One wonders did any
copies of this 'baby Wac Corporal' survive to the present?
    Nine months after Malina had proposed  it the vehicles were taken to the
new facility at White Sands Proving Grounds, New Mexico. 
    Four rounds of the booster called  Tiny Tim were launched off the tower.
Two dummy rounds of the WAC  were  boosted  and then two with only partially
filled fuel tanks were flown to get experience with the radar tracking.
    These must have been counted as rounds 1 through 4 because on October 11
1945 a fully loaded round  5  was  made  ready.  The  16 foot long 1 foot in
diameter rocket stood flight ready. It  weighed 665 lbs and would be boosted
by 50,000 lbs of thrust before the 1500 lb thrust liquid motor took over. In
Malina's words the flight went like this:
" 11 October 1945 became  our  great  day  for  the  first flight of the WAC
(round 5) fully charged with propellant.  It  was a clear day. We craned our
necks to watch the  WAC's  smoke  trail  until  the engine stopped at around
80,000 ft. On the basis of radar tracking data for the 6th round of the WAC,
it was estimated that the  maximum  altitude reached was between 230,000 and
240,000 ft. The total time  of  flight  was  about  450 sec. or 7.5 min. the
velocity of the WAC at the end  of  the  burning was about 3,100 ft per sec.
The impact point of the first round  was around 3,500 ft. from the launcher,
which meant that the WAC  had  maintained a very satisfactory vertical path.

Article: 19817 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: launch report for central IL, 9/23/95
Date: 11 Oct 1995 03:49:48 GMT
Lines: 19
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

Mark Johnson ([email-masked]) wrote:

: Maybe we should pick a "favorite brand" of these things, private label them 
: and send a batch to S&T for cert as a no-thrust device.

: Waitaminit...if you look at the definition for 1/4A motors, it goes all the 
: way down to 0.00 N-sec. So even if they produce no thrust, they're still 
: 1/4A's.

: :-) :-)
: =============

Even if someone is picky and says it must be greater than 0.00, the fact
that smoke is coming out means there is SOME thrust, even if it's in the
range of thousandths or millionths of Newtons.  :)
--
Lee Reep 
 [email-masked] 

Article: 19818 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: A brief launch report, questions & comments
Date: 11 Oct 1995 01:18:06 GMT
Lines: 14
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

: The other thing is a bit stranger... ever since I was a young kid I have 
: noticed these strips of metal lying in the street.  I think they might be
: part of the pavement that pops loose, I seem to find them most often in the 
: gutter on older, beat-up roads.  Anyway, they're about 1/8" wide and usually 
: 6" long, and they're every bit as stiff as Estes engine hooks.  I clean them 
: up with sandpaper and bend them with pliers, and make my own hooks.  BTW, 
: anyone know what these things really are?

I think you have bristles from street cleaning brushes...

Someone a long time ago in another forum mention that they make nice
picks for working with ceramics as well.

BillW

Article: 19819 of rec.models.rockets
From: [email-masked] (William Nichols)
Subject: Cone Heads (conical rockets)
Date: 10 Oct 1995 23:26:11 GMT
Lines: 12
Message-ID: <[email-masked]>

I recall many years back that Centuri had a kit that was simply a cone
w/o fins, and I know that Quest has a couple of kits that rely on body
shape for stability.

I'd like to explore the subject of conical model rockets. What unique
stability issues exist, if any? How does one calculate the CP? Is it a
good or bad idea to have an air inlet up front near the pointy end of
the cone? And, how stiff does the body need to be to avoid collapsing
during flight?

- Bill

Article: 19820 of rec.models.rockets
From: Justin Gleiter <[email-masked]>
Subject: Re: Confirmed at 14 years?
Date: Tue, 10 Oct 95 18:48:47 PDT
Lines: 19
Message-ID: <[email-masked]>
References: <mgreenl.813338256@hubcap>

In article <mgreenl.813338256@hubcap>, <[email-masked]> writes:

> I got confirmed to fly class B motors at only 14 years old.
> I heard someone say you had to be 18--is this true? I have flown
> lots of class B motors, even clusters of class B. Thanx.

Yes you have to be 18 in order to be confirmed legit.  Was your card signed 
recently or was this a few years ago?  You can still fly HPR, as most people 
usually don't mind.  Out of my numerous HPR flights from H to L 
class(cluster and staging too!), I was only given a hard time once at LDRS 
14(some RSO from Texas)when I checked in an H class flight.  As long as you 
know what you are doing and have someone to get your motors, it should be 
fine, but you still can't be legally certified.

Justin Gleiter

"No sense makes sense"--Charles Manson 

Article: 19821 of rec.models.rockets
From: [email-masked] (Anonymous)
Subject: Re: LOC 4 Sale
Date: 10 Oct 1995 19:30:19 +0100
Lines: 24
Message-ID: <[email-masked]>
References: <[email-masked]>
XComm: Replay may or may not approve of the content of this posting
XComm: Report misuse of this automated service to <[email-masked]>

In article <[email-masked]>, [email-masked] (Lee Reep) wrote:

> The latest HPR has a full page ad telling interested folks to
> contact LOC if you want to receive "an informative perspective
> package" (prospectus?).
> 
> Ad reads:
> 
> So ... you want a sneak preview for 96?
> 
> Preview This!
> 
> LOC/PRECISION is For Sale ...
> 
> I'm sick of my job, anyone wanna go half'sies?  :)
> 
> --
> Lee Reep 
>  [email-masked] 

If anyone is seriously considering this I have some insights to offer on a
kit production business.

Jerry

Article: 19822 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: plans
Date: 11 Oct 1995 04:15:21 GMT
Lines: 26
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Kevin Forsyth ([email-masked]) wrote:
:
: Anonymous ftp to sunsite.unc.edu for 
:
:   /pub/archives/rec.models.rockets/PLANS/night.zip
:
: Zipped version of postscript files, scanned from the original plans.
:
: That is, if you can get through to sunsite.

I cannot ftp to sunsite (and probably elsewhere), for some unknown reason
(I'm a Windows user running email and such off a UNIX server).

HOWEVER: I use Netscape to get to sunsite, and viewing and downloading
stuff is a breeze.   I have downloaded several of the Postscript
plans onto floppy, and taken them home for printing on a LaserJet
with Postscript.

Try http://sunsite.unc.edu to get in at high level, or append the
/pub/archives/rec.models.rockets/.... as needed.  Don't forget to 
add a "Bookmark" so you can easily reconnect in the future without
typing in the long URLs.
--
Lee Reep 
 [email-masked] 

Article: 19823 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: sunsite software
Date: 11 Oct 1995 04:31:09 GMT
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]>

Wolfram v.Kiparsky ([email-masked]) wrote:
: I've read the RMR FAQ, and notice that there is no description any software.

: I've downloaded a few of the programs, but

:  does anyone have a particular fondness for any of the code that is
: available at sunsite.unc.edu?

: Is any of it particularly useful?

Our group uses RSIM, a far superior program for altitude prediction
than the more commonly used, and known, RASP.  RSIM has a engine
editor that is really easy to use.  I've added several newer Aerotech
motors that were not modelled previously.  Try this with even any of
the commercially sold programs.  I don't think any of them allow
you to add new motor files on your own.  RSIM will plot and print
flight data also.

The only feature I'd really like to see is some better way to predict
or model Cd.

I've downloaded a few others, like the Cp programs, but have not tired 
them out yet.
--
Lee Reep 
 [email-masked] 

Article: 19824 of rec.models.rockets
From: [email-masked] (Greg Cimmarrusti)
Subject: Camera Payload
Date: 11 Oct 1995 03:21:39 GMT
Lines: 12
Message-ID: <[email-masked]>

I am looking for plans or a kit that will put a 35mm camera in the
payload section of a reasonably priced high powered rocket.  I am just
getting into HPR.  I have been facinated with the Estes Astrocam.  I
have replaced the launch vehicle with the Estes Maniac.  This allows me
to use "D" and "E" engines.  I have been having a problem though in
that only the first 2 of maybe 6 pictures will turn out.

Anyways, plans or a kit that will take continous pictures from launch
to apogee would be appreciated.

Greg Cimmarrusti
[email-masked]

Article: 19825 of rec.models.rockets
From: [email-masked] (Dangerous Dave)
Subject: Re: Epoxy Setting (was:Re: Could someone help with my Phoenix c.p. question ???)
Date: 11 Oct 1995 05:49:01 GMT
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]>

>   [email-masked] (March A. Briner) writes:
>  In article <[email-masked]> [email-masked] (Mark 
Johnson) writes:
>  >
>  >At an air temp of 95 F, epoxy in a plastic cup gets hot enough when it sets to 
>  >cause first and second degree burns. 
>
>  I've gotten 1st degree bruns several times from epoxy while it was 
>  setting into the formof a fillet. That got DAMN hot!
>
>  					Marc

Dang, Marc,

Got to watch out when you use fast hardners at high ambient temperatures. Mass will cause a 
considerable exotherm problem also. Important thing is:  wear gloves!!! The amine hardners in 
epoxy will cause you to sensitize!!!

Take it easy,

Daaaaaaaaaaaaaaaavvvvvvvvvvvvvvvvveeeeeeeeeeeeeeeeeeee

WARNING!!! An address change is eminant. Stay tuned for updates.
*************************************************************************
*  [email-masked]; [email-masked]                                    *
*  ftp://ftp.elite.net/pub/users/rocket/  http://www.elite.net/~rocket/ *
*************************************************************************

Article: 19826 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: 5 minute epoxy
Date: 11 Oct 1995 04:52:09 GMT
Lines: 17
Message-ID: <[email-masked]>

I saw several comments in other posts referencing my kidding 
someone about using duct tape, and recommending 5 minute epoxy. 
Several comments recommending not to use 5 minute epoxy, and in 
general, I agree.

However, field repairs is an excellent usage for this stuff!  The
whole idea is to get it flying again THAT DAY.  If it doesn't last,
no problem.  Do it right with 30 minute epoxy when you get home.

The fin I repaired with the Devcon 5 minute stuff is still holding
strong, so I left it as-is.  I've also seen 5 minute stuff that
never really seems to set strong, so your mileage may vary.

--
Lee Reep 
 [email-masked] 

Article: 19827 of rec.models.rockets
From: [email-masked] (Dangerous Dave)
Subject: Re: Epoxy Setting (was:Re: Could someone help with my Phoenix c.p. question ???)
Date: 11 Oct 1995 05:53:10 GMT
Lines: 25
Message-ID: <[email-masked]>
References: <[email-masked]>

>   [email-masked] (Judge LI) writes:
>  >>At an air temp of 95 F, epoxy in a plastic cup gets hot enough when it
>  sets to 
>  >>cause first and second degree burns. The temperature rise is quite 
>  >>significant. Haven't seen it melt a cup, but it wouldn't surprise me.
>
>  I've seen the cup melt - I was just screwing around and wanted a nice hunk
>  of epoxy so I poured it into a plastic cup and after a few minutes the
>  stuff started to melt and smoke and a whole bunch of nasty stuff. 
>
>>>>

You should see what happens when you mix >pound and let it exotherm!!! Spontaneous 
combustion is very likely!

Take it easy,

Daaaaaaaaaaaaaaaavvvvvvvvvvvvvvvvveeeeeeeeeeeeeeeeeeee

WARNING!!! An address change is eminant. Stay tuned for updates.
*************************************************************************
*  [email-masked]; [email-masked]                                    *
*  ftp://ftp.elite.net/pub/users/rocket/  http://www.elite.net/~rocket/ *
*************************************************************************

Article: 19828 of rec.models.rockets
From: [email-masked] (Dangerous Dave)
Subject: Re: 5 minute epoxy
Date: 11 Oct 1995 05:58:42 GMT
Lines: 37
Message-ID: <[email-masked]>
References: <[email-masked]>

>   [email-masked] (Lee Reep) writes:
>  I saw several comments in other posts referencing my kidding 
>  someone about using duct tape, and recommending 5 minute epoxy. 
>  Several comments recommending not to use 5 minute epoxy, and in 
>  general, I agree.
>
>  However, field repairs is an excellent usage for this stuff!  The
>  whole idea is to get it flying again THAT DAY.  If it doesn't last,
>  no problem.  Do it right with 30 minute epoxy when you get home.
>
>  The fin I repaired with the Devcon 5 minute stuff is still holding
>  strong, so I left it as-is.  I've also seen 5 minute stuff that
>  never really seems to set strong, so your mileage may vary.
>
>  --
>  Lee Reep 
>   [email-masked] 
>
>
>>>>

>From brand to brand the quality of your epoxy will vary. It depends on what the formulator 
decides to use for diluents and fillers. The only way you can actually know what your strength 
should be is with a spec sheet. Most formulators and distributors will supply one upon 
request. Be careful with your mixing proportions. If your mix is not precise, your final strength 
will suffer greatly.

Take it easy,

Daaaaaaaaaaaaaaaavvvvvvvvvvvvvvvvveeeeeeeeeeeeeeeeeeee

WARNING!!! An address change is eminant. Stay tuned for updates.
*************************************************************************
*  [email-masked]; [email-masked]                                    *
*  ftp://ftp.elite.net/pub/users/rocket/  http://www.elite.net/~rocket/ *
*************************************************************************

Article: 19829 of rec.models.rockets
From: [email-masked] (Bob Parks)
Subject: Re: Glider Trimming (was Re: Design Book)
Date: Tue, 10 Oct 1995 23:42:13 -0700
Lines: 53
Message-ID: <[email-masked]>
References: <199510101718.MAA00819@cybl35>

In article <199510101718.MAA00819@cybl35>, [email-masked] (Mark Bundick) wrote:

> "Bullet" Bob Kaplow ([email-masked]) wrote
> 
> > The ONLY way to accurately place the CG is to compute the "neutral point" 
> 
> > (the BG equivalent of the CP, in fact the equations for fins and wings 
> 
> > match), decide on a stability margin (% of wing chord, usually about 20% 
> 
> > for free flight models)
> 
> While the stated procedure is correct, the margin's a bit hefty.  Most world
> class free flight models run 10% or less.  I generally don't run below that,
> but at 10% there's sufficent stability to work without being terribly tricky
> to trim.  I suggest dedicated competitors try a static margin, hand
launch or
> fly the bird, then see how they like the performance vs. ease of trim
results
> and then either widen or reduce their margin on the next flight or design.

Well, it depends on how accurately you calculated the neutral point.. for
a simple TVC only based approach, it will estimate a point well aft of the
the true neutral point... so a 20% margin may be OK.

If the method includes things like the effect of wing downwash on the
tail, the aspect ratio of the wings and tails and the slope of the lift vs
angle of attack curve for both the wing and tail,then the method might be
reasonably accurate, and a smaller margin will be appropriate.  Note that
nobody REALLY knows what the lift curve slopes are for small FF BG
airfoils.. (actually the curves are not even straight like they are at
higher RN)

Probably the best way to set the CG is flight test... you want a
reasonable margin to avoid death dives and spiral dives... so play the
incidence and CG until you get it.  In particular, try some "bad" hand
tosses that put the glider in unusual attiudes and see how it recovers.

I always thought that to get good "robust" trim, you want something that
can recover from any attiude with less than a 20 or 30 ft altitude loss..
this generally means some sort of variable geometry to get a good boost.
(ie flaps or elevator setting change, not just a CG shift)

Bob

-- 
*********************************************************************
*  Bob Parks                         You can surf the Net...        *
*  [email-masked]               or you can be the one          *
*  [email-masked]         making the waves.              *
*  (408) 253-0246                           D. Plotnikoff, 1995     *
*********************************************************************

Article: 19830 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: 5 minute epoxy
Date: 11 Oct 1995 06:53:10 GMT
Lines: 5
Message-ID: <[email-masked]>
References: <[email-masked]>

I saw DEVCON "1-minute" epoxy in the hardware store the other day.

It was on sale - maybe it doesn't work well enough for anyone!

BillW

Article: 19831 of rec.models.rockets
From: Mark or Carlin <[email-masked]>
Subject: Re: First Arotech Rocket
Date: 11 Oct 1995 07:19:03 GMT
Lines: 11
Message-ID: <[email-masked]>
References: <[email-masked]>

     I'm not sure if it will answer all of your questions, and you may have 
read it already, but you might want to read the rec.models.rockets FAQ.
You can download the text version via FTP from sunsite.unc.edu at
/pub/archives/rec.models.rockets or view it in HTML at
www.ior.com/~markcln/tgate.htm (look under "References")

The FAQ is huge, but it tells a LOT.

Carlin
[email-masked]

Article: 19832 of rec.models.rockets
From: james McMurray <[email-masked]>
Subject: Re: A brief launch report, questions & comments
Date: 11 Oct 1995 07:13:30 GMT
Lines: 7
Message-ID: <[email-masked]>
References: <[email-masked]>

Those strips of metal you find in the streets are called spinkys.
They fall out of the brushes that are on street sweepers.  The 
possible uses will probably never end.  I use them for everything 
from engine hooks to bookmarks.  To successfully bend them you 
need to aneal them with a torch.
I look upon them as an urban resource.
Regards James

Article: 19833 of rec.models.rockets
From: [email-masked] (kingrat)
Subject: Plugging booster motors
Date: 11 Oct 1995 01:09:49 GMT
Lines: 16
Message-ID: <[email-masked]>

As far as I know it's possible. I've never plugged a D motor but I've 
seen it done. As far as the NAR rule about modifying motors goes, I don't 
think it applies to this. I think that's so members won't try to, for 
example say shorten a delay or cut a motor apart and try to add more 
propellant, etc... I don't think it applies to plugging the motor because 
one of the places I've seen it done was a NAR event for D rocket glider. 
(I think that's what it's called when the motor stays in and the rocket 
glides down. I've been into high power too long to remember) 

Then again, modifying composite motors is against Tripoli policy but some 
manufacturers used to include instructions for it. Who knows. :)

Eric Specht
Tripoli 1755
See you at Danville....

Article: 19834 of rec.models.rockets
From: [email-masked] (DavidlB145)
Subject: Tripoli  Membership
Date: 11 Oct 1995 04:20:24 -0400
Lines: 2
Message-ID: <[email-masked]>

I  renewed  my  membership  a  couple  of  months  ago  yet  have  heard 
nothing  back.  Is  this  typical?

Article: 19835 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Igniting flashbulbs?
Date: 11 Oct 1995 08:31:52 GMT
Lines: 26
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, Lee Reep ([email-masked]) 
says...
>
>
>Polaroid 600 flashbars work, but you may find it difficult
>to find them.  I bought some two years ago at Walmart, but our store no
>longer carries them.

I get Flashbars for my SX-70 at the local grocery store (Safeway) -- 
same place I buy film for it.  They seem to have plenty of them in 
stock, and there's no indication they've been discontinued.  In fact, 
there's better support for these cameras (nearing 25 years old) than for 
the much newer Kodak Disc cameras, which used the Flip Flash, or even 
the contemporary Instamatic X cameras that used 126 or 110 film and 
Magicubes.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19836 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: A brief launch report, questions & comments
Date: 11 Oct 1995 08:33:45 GMT
Lines: 41
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, Jane Marie Culver 
([email-masked]) says...
>
>Kevin Forsyth ([email-masked]) wrote:
>:
>:
>:
>: The other thing is a bit stranger... ever since I was a young kid I 
have 
>: noticed these strips of metal lying in the street.  I think they 
might be
>: part of the pavement that pops loose, I seem to find them most often 
in the 
>: gutter on older, beat-up roads.  Anyway, they're about 1/8" wide and 
usually 
>: 6" long, and they're every bit as stiff as Estes engine hooks.  I 
clean them 
>: up with sandpaper and bend them with pliers, and make my own hooks.
BTW, 
>: anyone know what these things really are?
>
>I remember those things too!  I can remember picking them out of the 
streets
>20 years ago in Milwaukee, WI.  Wonder what they are?
>
>

I'd guess they're broken bristles from the wire brushes in a street 
sweeper.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19837 of rec.models.rockets
From: [email-masked] (PaulDiming)
Subject: Re: Launch Report, Birmingham, AL
Date: 11 Oct 1995 04:38:24 -0400
Lines: 19
Message-ID: <[email-masked]>
References: <[email-masked]>

Great report!  It sounds like you know the possible reasons: Shock cord
mount, burn through,  break.  Perhaps others will come up with some more
ideas.  I'm just a newbie like you.

You know that saying "_hit happens?"  Well with this sport, Murphy is
lurking around every corner.  However, it's really not just chance. 
Learning rocket building technics, prep,  launch and flying advice will
substantially reduce your losses.  But.... you still will have losses.  I
fight that by building more rockets than I loose!  That way, I'm always
winning against Murphy (I know, that's a dillusion).

The question of the day, is the shock cord mount and cord still attached
to the body tube you recovered?  Dumb question of course...

Keep at it,  this sport can be lot of fun - if you invest some time
learning how to beat our friend Mr. Murphy!

Paul.
Fly Baby Fly!

Article: 19838 of rec.models.rockets
From: [email-masked] (PaulDiming)
Subject: Re: A brief launch report, questions & comments
Date: 11 Oct 1995 04:48:19 -0400
Lines: 12
Message-ID: <[email-masked]>
References: <[email-masked]>

Kevin wrote:

>> One is silver mylar sheet, the kind of stuff they use in greenhouses 
(and party balloons). <<

Where can I easily find this stuff?  I have heard that those emergency
blankets sportsmen use are made of the same stuff.  True?  Should I go out
and buy balloons? (sounds wierd).  This stuff does sound like good
streamer and chute material!

Paul.
Fly Baby Fly!

Article: 19839 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: Re: New CDH arrivals
Date: 11 Oct 1995 09:29:38 GMT
Lines: 26
Message-ID: <[email-masked]>
References: <[email-masked]>

Kevin Nolan <[email-masked]> wrote:
>   We received our first shipment of the Rocketman Enterprises LDRS-XIV
>
>videotapes today. They're $19.99 each. (Your's is on the way John.)
>
>     Along with the tapes we also received their LDRS T-shirts in M. L & XL
>
>sizes ($14.99 each), and LDRS mesh ballcaps at $9.99 each. The new Rocketman
>
>catalog is now available, listing their line of kits (up to enormous sizes!)
>
>It's $3.
>
>
>-- 
>"3"     Kevin Nolan      Countdown Hobbies; 74640,[email-masked]
>"2"     NAR 16148        800/810-0281; 203/790-9010 (24 hr. voice/fax)
>"1"     TRA 0943         3 P.T. Barnum Square, Bethel, CT 06801-1838
>"0"     NARCONN/CTRA         "Put Fun & Excitement in Your Life"

alright!  Can't wait!  I'll get a case of Pale Ale, and head over to friend's 
place for fun and laughs! Thanx!

-- 
John Dunbar

Article: 19840 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: Re: Fins for Scratch built?
Date: 11 Oct 1995 09:40:32 GMT
Lines: 35
Message-ID: <[email-masked]>
References: <[email-masked]>

[email-masked] (MonkyTrama) wrote:
>I was wondering if there were any companys that sell fins alone. since i
>have no access to any adequit cutting devices, i would have to buy some,
>or pay some one to cut them. Any information would help a great deal
>Thanx
>Matt
>
>

Hey Matt, if I may suggest:

I don't have alot of fancy equipment either.  So what I do is I get to know 
people who have those nice band saws, tables saws, ect..  Then I barter my
services, talents, or skills in trade for use of thier equipment.

Also, in the R/C mags, there are companies who sell low price and decent table
saws starting at ~$250.00.  I know that sounds like alot, and it is, but if 
you plan to build for the remainder of your life ( long one :) ) , its a 
worthy investment. Call Tower Hobbies 800 637 6050, or better yet call
Micro-Mark at 800 225 1066.  They specialize in small tools and equipment.

I usually cut my own stuff at friend's houses, or go down to a lumber yard, 
and for about $20, they will cut most of my stuff for me if I ask nicely :)

Now check out garage sells ... there is alot of neat tools cheap there.  Try 
a neighborhood where the people tend to be older.  Usually the male dies 
first, and his widow just wants to clean out the basement or garage.  You get
the best deals here!  Yeah I now it sounds morbid, but death is a part of 
life.  We should all die in our sleep at 90 something. 

Ok, thats about it.  Hope  the suggestions help.

-- 
John Dunbar

Article: 19841 of rec.models.rockets
From: [email-masked] (DaveEF)
Subject: Re: A brief launch report, questions & comments
Date: 11 Oct 1995 06:19:15 -0400
Lines: 22
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>,
[email-masked]  (Kevin Forsyth) writes:

>The other thing is a bit stranger... ever since I was a young kid I have 
>noticed these strips of metal lying in the street.  I think they might be
>part of the pavement that pops loose, I seem to find them most often in
the 
>gutter on older, beat-up roads.  Anyway, they're about 1/8" wide and
usually 
>6" long, and they're every bit as stiff as Estes engine hooks.  I clean
them 
>up with sandpaper and bend them with pliers, and make my own hooks.  BTW,

>anyone know what these things really are?

They come off of the brushes when the street sweeper goes by. Your rocket
building sounds about as agressive as mine. I'm not happy unless I've got
a minimum of two building projects going at all times!

Dave Falkner
Tri City Sky Busters NAR Section 535
NAR 62073

Article: 19842 of rec.models.rockets
From: [email-masked] (PaulDiming)
Subject: Launch Report, Richmond, VA (family style!)
Date: 11 Oct 1995 06:29:17 -0400
Lines: 61
Message-ID: <[email-masked]>

On Saturday, we had a successful launch in great autumn weather: 75F,
light winds 5-10 mph.  Gorgeous blue sky for watching high altitude
launches.

Summary: We launched some new models today for the first time, an Alpha
III, Bailout, Mosquito and an X-Wing.  All were Estes models since I have
not yet (but will soon!) tried other manufacturers.  All flights were
succesful with good recoveries except the X-Wing.  It's chute failed to
open and it took the fast way down!  The new Alpha III replaced the one I
lost on the high school roof (apparently school roofs are favorite
recovery areas!).

Detail:
Alpha III           A8-3, 1st launch,  A little wobbly due to a bent fin.
Bailout            B4-2, Exceptional!  Action figure bailed out!.  My son
loved it!
BullPup           A8-3, 1st launch.  Not a high flier, but impressive!
Mosquito         1/2A3-4T, 1st launch, Went out of sight.  Recovered fine!
Wow..

More Detail:

The Alpha III replaced my first Alpha III which I lost on the roof of the
local high school.  I hope to get at least twenty or so launches out of
this one.  My record was 10 on the last one.

Bailout is fast becoming quite a reliable model rocket.  Good
construction.  Plastic fin unit.  Large size.  Even the action figure (kid
supplied!) looks cool coming down on their own chute!  My advice to a Mom
or Dad:  Don't use your kids action figure, buy your own!  On one of my
first flights, I lost my seven year old son's action figure and he was not
pleased! . I made a deal with him and bought one to replace his and one of
my own.  Now if I loose another, it won't be his!

BullPup is a great display rocket as well as one that can actually fly! 
Putting on the decals is a bit of a challenge.... I broke a few but
managed to get them on OK.  Looks great.  Flew straight.  Apparently it's
not a high flier on A motors.  But I hear a lot of folks like this rocket.
 Try it, you'll like it!

Mosquito is.... quite small.  That's an understatement!  Only 3.9" tall. 
Very fast to build.  Rocket fanatics can still like this rocket: it has
balsa fins!  But.... start with the same or equivalent engine!  This
sucker really flies high.  We lost track of it.  Recommendation:  Paint it
a bright flourescent (sp?) color.  I quickly found this rocket because it
almost glowed in the dark!  Also... don't fly it in a field with tall
grass, this rocket is realllll small.

plastic model.  I think the "flying" part is questionable.  The body tube
is very narrow (about 18 mm) making it difficult to stow a chute.  My
chute didn't open right.  Talk about a nose dive!!!  But, it does bounce
nicely!   Some damage, two of four broken wings.  The Laser cannon kind of
aim to the left or right (sort of like us older guys!)

Well, have fun.  I sure did!

Paul.

Fly Baby Fly!

Article: 19843 of rec.models.rockets
From: Xiaoyi Eve Zhang <[email-masked]>
Subject: Re: airfoiling fins
Date: Wed, 11 Oct 1995 07:24:55 -0400
Lines: 20
Message-ID: <[email-masked]>
References: <[email-masked]>

This is a subject I've been thinking about recently too. For the record,
I use rounded leading edges and sharp trailing edges. If I had the 
technology, I'd do a true airfoil, with the thickest point about 40% down
the chord from the leading edge. (I guess you can't call this 'Camber' when
it's symmetric, cuz the average line coincides with the chord line).

Been thinking about the possibility of stall in a coning situation, where 
the angle of attack gets large - like maybe a thicker, more airfoiled
set of fins might prevent this problem somewhat in superroc competition. Also
unintended asymmetry of the fins may promote it. (e.g.; one fin stalls and
induces spin.) I know the problem is mostly one of coupled moments, and that
fins don't damp it out; I'm just thinking of making the situtation harder
to get into. 

Also, benn thinking that a lug in the fin/body joint might be a good idea
(not in superroc, obviously :-) with a flat, thin fin, but not with a thick,
airfoiled fin where the warp causes faster local air flow.

Oh well... So much for streamline of consciousness.
-Larry Curcio 

Article: 19844 of rec.models.rockets
From: [email-masked] (Awards1)
Subject: Re: How big are they today ?
Date: 11 Oct 1995 07:37:12 -0400
Lines: 7
Message-ID: <[email-masked]>
References: <[email-masked]>

Not just a kid's sport anymore, huh! I am always surprised at how most
people think you are flying Estes C & D motors when you mention that your
hobby is rocketry. -Then they have alot more questions, when you start
talking about 10,000 to 15,000 altitudes.

Tracy Dungan
Tripoli OK

Article: 19845 of rec.models.rockets
From: [email-masked] (Awards1)
Subject: Re: Tripoli  Membership
Date: 11 Oct 1995 07:39:58 -0400
Lines: 7
Message-ID: <[email-masked]>
References: <[email-masked]>

I think it is normal, from what other Tripoli members have told me. I
think you are supposed to get back another card showing your current
certification level and the new expiration date of your membership.
I am waiting on word of my renewal also.

Tracy Dungan
Tripoli OK

Article: 19846 of rec.models.rockets
From: [email-masked] (Blockhed)
Subject: Re: Cone Heads (conical rockets)
Date: 11 Oct 1995 08:45:08 -0400
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]>

I find your suffestion about conical rocket bodies to be very interesting.
I am a woodturner by profession, so it sould be easy for me to make a tall
thin cone from Basswood, with the pocket for the engine drilled into the
tail end, and a hole for the launch rod. On th face of it, I would think
the drag from the wide base would keep it stable ( if not faast and
high-flying)... but I don't pretend to know the second thing about 
aerodynamics. I'm tempted to just make a small one and try it out by
myself in the back field. 

So, I too would love to hear some discussion about this topic

Article: 19847 of rec.models.rockets
From: [email-masked] (Mark Johnson)
Subject: Re: airfoiling fins
Date: Wed, 11 Oct 1995 07:34:12
Lines: 22
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> "John P. Petrakis" <[email-masked]> writes:

>What do most folks do when airfoiling 5-ply 1/8 inch plywood?
>I assume few people out there have the patience to put a full
>circular arc supersonic airfoil over the entire surface.  What is
>the most favored practice when it comes to this?  Leading and
>trailing edges sharp, rounded or what?

I normally do leading and trailing edges sharp, with about a 3/8 inch beveled 
edge. Rather than sanding till the cows come home, I ordinarily use a Dremel 
tool to rough-in the bevels and then finish with sandpaper, starting at about 
150 grit and working down.

On 1/8 stuff, I just round over the edges, again with the Dremel tool. The 
beveled-edge treatment I use on 3/16 and heavier stock. Surface finishing on 
all plywood begins with an orbital sander and 220 grit paper, with hand 
finishing at 400 before I start in with sealers.
====================
Mark Johnson                       USnail: Symbios Logic, Inc
E-mail:  [email-masked]          OEM RAID Business Team
Voice: (316) 636-8189 [V+654-8189]         3718 N. Rock Rd.
Visit our web page: http://www.symbios.com Wichita, KS  67226

Article: 19848 of rec.models.rockets
From: [email-masked] (Ryan Woebkenberg)
Subject: Re: US Spacemodeling Team Selection Results
Date: 11 Oct 1995 13:05:42 GMT
Lines: 25
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>,
nal040700-Mckiou <[email-masked]> wrote:
>
>in the second round and did not max.  I do not know his time.  The
>second round was tough on a number of people.  I think George G,
>Herb and I were the only one's to max it.  But, I could be wrong.

I think it was actually the 3rd round that was tough on a lot of people
All entreys maxed the first round.  All entries but George Reibesel<sp>
, Ben Reberto <sp>, and I maxed teh 2nd round.  And only Kevin,
George G, and Herb maxed the 3rd.  The 3rd round also had 2 DQes 
in it ( George R and I )  and had several flyers miss max by 
about 15 seconds... 

-- Ryan "Chad can fly rc, really"  Woebkenberg

--------------------------------------------------------------------------
[email-masked]  NAR 49363  TRA 1253 AMA 544846 
Come to NARAM 38.  If you do, I will try and have some interesting crashes 
--------------------------------------------------------------------------

Article: 19849 of rec.models.rockets
From: [email-masked] (al jackson)
Subject: First Wac/Corporal Flight 50 Years Ago Today
Date: Wed, 11 Oct 1995 08:28:15
Lines: 111
Message-ID: <[email-masked]>

Sorry the server here glitched , here is the whole essay.
Al
                       Texas Rocket Grandmaster 
                          by  Al Jackson

    I travel  from  Houston  to  Austin  by  highway  290  fairly often, and
sometimes I stop at Brenham Texas for  lunch. I skip the fast food joints on
290 and go downtown.  It  is  a  beautiful  small  town  with a charming old
downtown (founded in 1844). Only recently  have I become aware that a native
Texan from Brenham fulfilled  a  dream  started  by Robert Goddard, in fact
doing in 10 months what  Goddard  had  for  twenty years to accomplish. Even
more than that he was co-founder  of the Jet Propulsion Laboratory, JPL, and
co-founder of Aerojet General. By 1945  he  had eclipsed Goddard as the most
important American rocket scientist. He  was  a consummate researcher in the
theoretical engineering of rocketry and  a  master manager of several rocket
and rocket vehicle projects  for  the  U.S.    Army.    So who was the Texas
pioneer 'Wernher von Braun'? He is Dr. Frank J Malina from Brenham Texas.
    Malina was the originator and leader  of a project that has an important
anniversary on October 11 this year. It  will be the 50th anniversary of the
first full up launch of  a  Wac-Corporal  sounding rocket. We tend to forget
that Goddard had a solid scientific use for his development of rockets, that
was to sound the upper atmosphere. We all love Goddard for his inventiveness
in rocket hardware and  his  stubborn  individualism,  and given time he may
have realized his sounding rocket  dream.  However while he struggled in the
New Mexico desert in 1936  Frank  Malina  ,  still a graduate student at Cal
Tech, had put on the wall of his office a chart of how a successful sounding
rocket project might be accomplished.  Unlike Goddard he recognized the need
for a team and a choice of team captains.
    Malina's dream was interrupted by  World  War  II. Along with his mentor
Theodore von Karman (the great  20th century aerodynamicist) he directed the
development of the Jet Assisted Take Off,  JATO, rockets for use by the Army
Air Force. This work for the  U.S.  Army  lead  to the formation of JPL, and
when von Karman moved the Pentagon  as  a consultant Malina became the first
director of JPL. There is a  straight  line heritage from these solid rocket
motors to the intercontinental missiles  in the American defense arsenal and
even up to the current Space Shuttle booster motors. His involvement in this
project alone is enough to have made him a famous rocketeer.
    In 1944 Dr. Malina was  sent  to  England and France to inspect salvaged
V2s and V1 launch sites. Returning by  plane over the Atlantic he decided to
ask the Army ordnance Department to  fund his cherished goal of building and
launching a vehicle to sound the  upper atmosphere in regions that could not
be reached by balloons.  This  was  December  of  1944. From designs by H.S.
Tsien and Malina, he  and  Homer  Stewart  submitted  and  got approval on a
proposal to launch a sounding rocket with a 25 lb payload to 100,000 ft.
    There had already been a  program  started  at  the newly founded JPL to
build military rockets. Malina organized  a team to use components developed
from this program. It is amazing  that  the Von Karman-Malina program at JPL
during WWII accomplished ,  on  a  smaller  scale, almost the same technical
objectives as von Braun's  huge  V2  project.  A  viable liquid rocket motor
using nitric acid and aniline with 1500  lbs of thrust was developed and the
Private-series of missiles. The main  difference  being the V2's much larger
rocket motor  and  especially  the  guidance  system  which  was still being
researched at JPL by the end of the War.
    Once the project  was  approved  Malnia  and  his  JPL  crew turned over
several ideas for the sounding rocket.  It  turned out that the solid rocket
motors would be too heavy  for  the  flight.  They  needed a long burn light
weight rocket. So a liquid motor  powered  vehicle boosted quickly to a high
speed was decided upon. They  needed  the  initial  boost in order to gain a
sufficient amount of stability from the  vehicle  fins since they had yet to
developed an active onboard guidance system. The booster system used some of
the solid  rocket  technology  in  the  JATO  units  that  JPL  had already
fashioned. The booster and 2nd stage liquid rocket were to be launched using
a 60 ft tower.
    In July of 1945 the  flight  characteristics  of the booster were tested
with a 1/5 scale model at  Goldstone  Lake, California. The tests showed the
viability of the solid booster  system  and a three fin stabilization system
rather than four  fins  favored  by  ordnance  experts.  One wonders did any
copies of this 'baby Wac Corporal' survive to the present?
    Nine months after Malina had proposed  it the vehicles were taken to the
new facility at White Sands Proving Grounds, New Mexico. 
    Four rounds of the booster called  Tiny Tim were launched off the tower.
Two dummy rounds of the WAC  were  boosted  and then two with only partially
filled fuel tanks were flown to get experience with the radar tracking.
    These must have been counted as rounds 1 through 4 because on October 11
1945 a fully loaded round  5  was  made  ready.  The  16 foot long 1 foot in
diameter rocket stood flight ready. It  weighed 665 lbs and would be boosted
by 50,000 lbs of thrust before the 1500 lb thrust liquid motor took over. In
Malina's words the flight went like this:
" 11 October 1945 became  our  great  day  for  the  first flight of the WAC
(round 5) fully charged with propellant.  It  was a clear day. We craned our
necks to watch the  WAC's  smoke  trail  until  the engine stopped at around
80,000 ft. On the basis of radar tracking data for the 6th round of the WAC,
it was estimated that the  maximum  altitude reached was between 230,000 and
240,000 ft. The total time  of  flight  was  about  450 sec. or 7.5 min. the
velocity of the WAC at the end  of  the  burning was about 3,100 ft per sec.
The impact point of the first round  was around 3,500 ft. from the launcher,
which meant that the WAC  had  maintained a very satisfactory vertical path.
Success!"
    That 43 mile flight was a  world  record,  for even the more advanced V2
had  not  been  launched  to  such  an  altitude  yet.  It  was  an  amazing
achievement. In 10 months Malina  and  his  crew had convinced and built the
sounding rocket Goddard had dreamed of and made such a contribution to. Soon
there followed the captured V2  flights  from  New Mexico and other sounding
rocket programs.
    Malina , who had visited Goddard in  New Mexico, and had been invited by
Goddard to  work  for  him  before  WWII  intervened,  noted something about
attaining hard technological goals.  He  had  headed  a large team of people
working together just as von  Braun  had  run  a much larger team in Germany
(Malina and von Braun were both almost the same age). Malina remarked, " The
large number of people involved in this (WAC Corporal) program indicates why
the dreams of individuals  and  small  groups  of  rocket enthusiasts in the
1920's and 1930's to  design,  construct  and  test a high altitude sounding
rocket had little  chance  of  success.  Fortunately,  most  pioneers do not
foresee all of the practical implications  of their dreams. No doubt if they
were able to do so, few new wild ideas will ever be tried."
    It will be good this year  to  remember fellow Texan Dr. Frank Malina, a
man not as well known as Dr.  Goddard  or  Dr. von Braun but a rocketeer who
had profound  and  lasting  impact  on  the  American  development  of rocket
vehicles, astronautics and spaceflight.

Article: 19850 of rec.models.rockets
From: [email-masked] (Wilfred van Bergen)
Subject: Re: Could someone help with my Phoenix c.p. question ???
Date: 11 Oct 1995 14:21:41 GMT
Lines: 17
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>  <[email-masked]> <[email-masked]>

: 5) Avoid impacts with dry lake beds :-)
or high grass!

: 6) I've computed the CP on mine to be 34.14" from the nose tip, or 8.36" in
: front of the square fin leadig edge. A LOT of that forward raked fin is in
: front of the CP, decreasing the stability of the model. Unfortunately, since
: it's a scale model, there is nothing you can do about this.
I have an Estes Phoenix which I launched last weekend three times with succes
on a D12-3 motor (sorry, but D is all I can get). Anyway, I follow this
thread for a while about the position of the CP and CG. For the 30" Estes
Phoenix the CP was calculated at 21.22" by cpcalc and 19.23" by centroid . I
noticed that for my Estes Phoenix the CG is just 3/4" down the start of the
front fins, giving a CP of about 22". It still worked fine though. Does any
one have a clue how the CP influences the flight of a rocket? I mean, can you
tell by the trajectory of the rocket wether it should be more up or down?

Cheers, Wilfred.

Article: 19851 of rec.models.rockets
From: [email-masked] (Wilfred van Bergen)
Subject: Re: airfoiling fins
Date: 11 Oct 1995 15:02:01 GMT
Lines: 11
Message-ID: <[email-masked]>
References: <[email-masked]>

John P. Petrakis ([email-masked]) wrote:
: What do most folks do when airfoiling 5-ply 1/8 inch plywood?

I made the Estes Phoenix with 8 balsa fins and a lot of sanding. I don't know
what the regular guys use, but I use Perma Grit tools to do this. They are
extremely sharp and stay that way. In fact, it don't matter wether I sand 
balsa or plywood, it's just as easy. First go for a triangular shape and the
round it up. Takes only a few mninutes when you get a hand on it.

Cheers, Wilfred van Bergen
	[email-masked]

Article: 19852 of rec.models.rockets
From: Paul <[email-masked]>
Subject: Re: Hybrid Motor Manufacturers?
Date: 11 Oct 1995 15:31:12 GMT
Lines: 14
Message-ID: <[email-masked]>
References: <[email-masked]>

James,

Hybrid motor manufacturers are currently HyperTech and AeroTech. 
 Addresses for both companies can be found in their ads in High 
Power Rocketry magazine, probably available at your local hobby 
shop.  If they don't have the mag, send me E-mail with your snail 
mail address and I'll have the publisher send you a copy.

Paul Gennrich
Prefect
Tripoli Coastal Georgia

-- 
Paul                   

Article: 19853 of rec.models.rockets
From: Christopher Beard <[email-masked]>
Subject: Re: Sperachutes
Date: Wed, 11 Oct 1995 11:19:41 -0400
Lines: 7
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

There is a new site on the internet called Leonardo Park @ 
http://www.hobbies.com that will link antiques, collectibles, and craft 
sites to make it easy for collectors and hobbyists to find good information.
Feel free to send me any links that you think are good.
Contact the Editor at [email-masked]

Article: 19854 of rec.models.rockets
From: Paul <[email-masked]>
Subject: Re: Plugging booster motors
Date: 11 Oct 1995 15:49:17 GMT
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]>

Bob, you were right on: >> It is without question a violation of 
the safety code. It is also quite possible, and IMHO quite safe. 
Without endorsing the practice, I do have one tip I picked up 
from those experienced with the practice before D11-P motors
were available. Do not use booster motors, but rather one of the
delay motors. <<

Again, without condoning modification of motors, I've found 
absolutely NO problems caused by simply stuffing biodegradable 
ejection wadding (cellulose insulation material) into the open 
end of D-motors and covering it with a couple layers of masking 
tape!  Tis sufficient to contain any flame from the motor and is 
certainly a heck of a lot faster than epoxy!

Paul Gennrich

-- 
Paul                   

Article: 19855 of rec.models.rockets
From: [email-masked]  (Kevin Forsyth)
Subject: Re: A brief launch report, questions & comments
Date: Wed, 11 Oct 1995  11:55 EDT
Lines: 29
Message-ID: <[email-masked]>
References: <[email-masked]>  <[email-masked]>

In Article <[email-masked]> "[email-masked] (PaulDiming)" says:
> Kevin wrote:
> 
> >> One is silver mylar sheet, the kind of stuff they use in greenhouses 
> (and party balloons). <<
> 
> Where can I easily find this stuff?  I have heard that those emergency
> blankets sportsmen use are made of the same stuff.  True?  Should I go out
> and buy balloons? (sounds wierd).  This stuff does sound like good
> streamer and chute material!
> 
> Paul.
> Fly Baby Fly!
> 
 
The stuff I'm using was leftovers from a big roll (4 feet x 50') a friend 
bought from an indoor gardening supply shop.  It's expensive this way... but 
would give you a lifetime supply.  I'm not sure, but I tend to think 
emergency blankets would be heavier, maybe too heavy.
 
I made a chute out of the stuff, but because I was paranoid about tearing I 
reinforced it with scotch tape around the edges and across the middle (like 
seams).  Unfortunately the tape made the chute stiff and after a couple of 
flights it failed to open.  However, the mylar is not as prone to tearing as 
I thought, if you only reinforce the corners where you attach the shroud 
lines it should work well.  I'm betting party balloons would work great-- 
plus they're already in a round shape, for an instant chute.
 
/kevin

Article: 19856 of rec.models.rockets
From: Paul <[email-masked]>
Subject: Re: What causes "chuffing" *exactly?
Date: 11 Oct 1995 16:06:31 GMT
Lines: 20
Message-ID: <[email-masked]>
References: <[email-masked]>

Hey, Observer, I'd have to give you the prize for the best answer 
I've seen on this question!

Most chuffs do indeed seem to be caused by ignition of the motor 
at the nozzle end of a core-burning motor- be the core a slot, a 
moon-burn style, a center core, or Bates grain geometry.  The 
problem, as I've seen it, is failure of the motor to ignight the 
entire burn surface, causing underpressurization of the motor.
I've seen more such tendancies on low efficiency moturs, such as 
Smoky Sams, but any motor can and will chuff if not ignited 
correctly!

Good answer!

Paul Gennrich
Prefect
Tripoli Coastal Georgia

-- 
Paul                   

Article: 19857 of rec.models.rockets
From: Paul <[email-masked]>
Subject: Re: What causes
Date: 11 Oct 1995 16:15:03 GMT
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]>

Hi, Todd!!

Perhaps a bit off topic (G) you asked: >> Sorry, but I have heard 
this name many times now.  Who is Paul G??? <<

He is the one, the GREAT OZ of HPR!!------- Nah, I'm simply 
prefect for Tripoli Coastal Georgia, and have been around HPR for 
almost 10 years.  I've formed 3 different rocketry groups in 
Coastal Georgia over the last many years, from local to NAR to 
Tripoli groups, and still simply enjoy the hobby for the 
challenge it produces.

I'm also the long-haired, bearded, ugly mudsucker in the flowered 
launch shirt that is pictured in HPR  magazine on occasion, and 
the designer of one of the more infamous rockets in the southeast 
US, specifically "The Bricks", designed to prove that if you 
push a brick fast enough it'll fly!  The rocket is a full scale 
model of three 3-hole red building bricks with fins and a nose 
wedge- never heard of a cone with a rectangular base- and 2 24mm 
motor mounts.  It's retired now, but was always flown on 2 D12 
boosters, as D12-3s had far too long a delay!

Thass about it, except that I'm also a card carrying member of 
the "Vocal Minority" of TRA, as officially designated by our 
esteemed president, Bruce Kelly.  Paul Gennrich  TRA#412

-- 
Paul                   

Article: 19858 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: Launch Report Questions
Date: 11 Oct 1995 16:21:05 GMT
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

JABeecher ([email-masked]) wrote:
: I am new to the Internet rocketry scene, so I wondered about the launch
: reports I have been reading.

: I enjoy reading them, and would like to report the activities of the
: Minneapolis Space Program's attempts at experimentation and launch.  Do we
: have to be an official organization?  Is there a standard format?

This is America!  You can post anything you want.  If you read this group
for awhile, you'll notice lots of different styles, not to mention LOTS
of differing opinions (mostly on rocketry, thank God).

Write away -- it's always nice to hear what other folks are doing.  :)

Only one comment on format - watch yoour margins.  Lots of folks haven't
mastered this too well, and you see plenty of line wraps, making postings
difficult to read.

I think you will find this group a fun one to read, and I believe all
of us have learned lots from the group.  There is tons of talent to
be found and captured here.

  Lee

--
Lee Reep 
 [email-masked] 

Article: 19859 of rec.models.rockets
From: [email-masked] (nal040700-Mckiou)
Subject: Re: US Spacemodeling Team Selection Results
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Date: Wed, 11 Oct 1995 18:57:06 GMT
Lines: 17

In article <[email-masked]>,
Ryan Woebkenberg <[email-masked]> wrote:

>
>I think it was actually the 3rd round that was tough on a lot of people
>All entreys maxed the first round.  All entries but George Reibesel<sp>
>, Ben Reberto <sp>, and I maxed teh 2nd round.  And only Kevin,
>George G, and Herb maxed the 3rd.  The 3rd round also had 2 DQes 
>in it ( George R and I )  and had several flyers miss max by 
>about 15 seconds... 
>

Right. I just got my official results last night.  My memory was
obviously clouded by my adrenaline during the third round <G>.  Actually
a number of people did quite well.  S8e seems to be growing.

Kevin

Article: 19860 of rec.models.rockets
From: [email-masked] (Mark Johnson)
Subject: Re: Cone Heads (conical rockets)
Date: Wed, 11 Oct 1995 11:30:40
Lines: 19
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> [email-masked] (William Nichols) writes:
>I'd like to explore the subject of conical model rockets. What unique
>stability issues exist, if any? How does one calculate the CP? Is it a
>good or bad idea to have an air inlet up front near the pointy end of
>the cone? And, how stiff does the body need to be to avoid collapsing
>during flight?

The CP of a cone is 2/3 of the way from the front of the cone to the back. As 
for stiffness, it's trial and error, pretty much. I would conjecture that an 
air inlet would cause more problems than it solves, but I don't know for sure. 

The "standard" work on the subject of conical model rockets is a report 
written in 1969 by Gary Schwede, and published in the October 1969 issue of 
_Model Rocketry_ magazine.  [I have a copy...]
===========
Mark Johnson                       USnail: Symbios Logic, Inc
E-mail:  [email-masked]          OEM RAID Business Team
Voice: (316) 636-8189 [V+654-8189]         3718 N. Rock Rd.
Visit our web page: http://www.symbios.com Wichita, KS  67226

Article: 19861 of rec.models.rockets
From: [email-masked] (Mark Johnson)
Subject: Re: sunsite software
Date: Wed, 11 Oct 1995 11:33:11
Lines: 26
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

>Wolfram v.Kiparsky ([email-masked]) wrote:
>: I've read the RMR FAQ, and notice that there is no description any software.

>: I've downloaded a few of the programs, but

>:  does anyone have a particular fondness for any of the code that is
>: available at sunsite.unc.edu?

>: Is any of it particularly useful?

#Begin Shameless plug

I've found Larry Curcio's DIGITRAK program and the associated Cd predictor 
(which uses the USAF DATCOM method) to be highly useful...especially since it 
does not only altitude prediction but also can do "backtracking" to allow Cd 
estimation and even altitude estimation based on time to apogee. Larry is an 
r.m.r regular who's been very responsive when I've found small bugs in the 
program.

#End shameless plug
===========
Mark Johnson                       USnail: Symbios Logic, Inc
E-mail:  [email-masked]          OEM RAID Business Team
Voice: (316) 636-8189 [V+654-8189]         3718 N. Rock Rd.
Visit our web page: http://www.symbios.com Wichita, KS  67226

Article: 19862 of rec.models.rockets
From: [email-masked] (Mark Jeghers)
Subject: Re: Fins for Scratch built?
Date: 11 Oct 1995 17:46:19 GMT
Lines: 45
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, [email-masked] says...
>
>[email-masked] (MonkyTrama) wrote:
>>I was wondering if there were any companys that sell fins alone. since i
>>have no access to any adequit cutting devices, i would have to buy some,
>>or pay some one to cut them. Any information would help a great deal
>>Thanx
>>Matt
>>
>>
>
>Hey Matt, if I may suggest:
>
>I don't have alot of fancy equipment either.  So what I do is I get to know 
>people who have those nice band saws, tables saws, ect..  Then I barter my
>services, talents, or skills in trade for use of thier equipment.
>
>Also, in the R/C mags, there are companies who sell low price and decent table
>saws starting at ~$250.00.

Good point here, John.  Let me just add that I got a small Sears table
saw for slightly over $100, and it cuts plywood fins just fine, including
delicious beveling on the edges.

>I usually cut my own stuff at friend's houses,

Another good point: Networking with each other!

That's why we have rocket clubs, eh ? :-)

Let me also point out that for local rocketeers (South Bay Area),
I am glad to have them come over and use my table saw to cut their
fins out.  Especially if you are a newbie who wants to learn how
to improve upon the fins often provided in low-end HPR kits; I can
help you replace those fins with better-tabbed fins for stronger
thru-the-wall mounting.

Just look me up in the AeroPac or LUNAR listings (or email me).

Mark Jeghers

>John Dunbar

Article: 19863 of rec.models.rockets
From: [email-masked] (Francis M. Dorer)
Subject: Re: Launch Report, Birmingham, AL
Date: 11 Oct 1995 15:25:39 GMT
Lines: 22
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> [email-masked] (Tommy Usher) writes:

Misc stuff about chute separation snipped.

>In any case, an interesting experience.  I am looking forward to building
>both a payload carrying rocket, and a multi-stage.  I may also invest in
>an Astro-Cam, but I would hate to have been flying one yesterday....
>
Not too big of a worry, as the AstroCam uses two shock cords.  One from
the booster to the cone, and then a doubled up cord from the cone to the
chute.

You also may want to look at Quest's method of using a piece of Kevlar
attached to the motor mount, then a piece of shock cord between the Kevlar
and the cone.

-- 
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
Launchpad is an experimental internet BBS. The views of its users do not 
necessarily represent those of UNC-Chapel Hill, OIT, or the SysOps.
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

Article: 19864 of rec.models.rockets
From: [email-masked] (Mark Johnson)
Subject: Re: 5 minute epoxy
Date: Wed, 11 Oct 1995 12:36:48
Lines: 37
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]> [email-masked] (Dangerous Dave) writes:

>From brand to brand the quality of your epoxy will vary. It depends on what the formulator 
>decides to use for diluents and fillers. The only way you can actually know what your strength 
>should be is with a spec sheet. Most formulators and distributors will supply one upon 
>request. Be careful with your mixing proportions. If your mix is not precise, your final strength 
>will suffer greatly.

Amen to this...even with hobby-grade stuff, where the hardener is severely 
filled to get to a 1:1 ratio, I've gotten *MUCH* better results on both 
adhesive and coating epoxy resins since I started with the simple expedient of 
using a set of cheap measuring spoons to make sure I get the amounts matched. 
30 minute stuff actually sets in 30 minutes, at around 70 degrees...and is 
paintable and quite strong overnight.

Cheap advice: hit the grocery store and buy a set of plastic measuring spoons 
for model-quantities of epoxy. Often these aren't particularly accurate (e.g. 
the 1/2 teaspoon may not be exactly twice the volume of the 1/4 teaspoon) but 
for 1:1 it doesn't make any difference. Typically I wipe them with an alcohol 
soaked rag between measuring resin and hardener, and immediately after 
measuring out the second component, rinse the measurement tool in alcohol and 
wipe it down. I'm still using the original 98c set of spoons I bought 2 years 
ago. 

For most uses, even on a fairly big HPR bird, two tablespoons or less of epoxy 
at a time is all I want to handle...more than that and I for one would rather 
let it set up and do another batch. Might be different if I was resin coating 
a 10' long 8" bird, of course.

And yes, Dave, I *do* wear rubber gloves. I keep a box of examining gloves on 
my workbench. Typically, unless I'm doing *really* small batches, I change 
gloves on every batch. I only use the respirator for airbrushing.
==============
Mark Johnson                       USnail: Symbios Logic, Inc
E-mail:  [email-masked]          OEM RAID Business Team
Voice: (316) 636-8189 [V+654-8189]         3718 N. Rock Rd.
Visit our web page: http://www.symbios.com Wichita, KS  67226

Article: 19865 of rec.models.rockets
From: [email-masked] (David Klouser)
Subject: Re: US Spacemodeling Team Selection Results
Date: 11 Oct 1995 18:25:10 GMT
Lines: 16
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

Kevin,

I timed Dave O'Bryan, who maxed both the 1st and 2nd rounds.  He made 
just a slight mistake in the third round or he would easily have made it 
to the 4th round.  I was letting him know as each minute passed.  His 
usual performance was to start to bring the model down at 5 minutes for a 
7 minute max.  That's what he did in the third round, but the air wasn't 
as nice as in the first 2 rounds, so he came down faster than he 
thought.  Missed the max by ~15 seconds.  I haven't done much RC RG 
flying yet, buy I'm learning just hanging out with you guys.  Congrats - 
you had a really nice model.  My prediction for the S8E team was you, 
Herb and George R.  I was close, but instead of George R, it was George G.
Good luck.

Ducky

Article: 19866 of rec.models.rockets
From: [email-masked] (Bob Parks)
Subject: Re: Plugging booster motors
Date: Wed, 11 Oct 1995 11:24:01 -0700
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, Paul
<[email-masked]> wrote:
> Again, without condoning modification of motors, I've found 
> absolutely NO problems caused by simply stuffing biodegradable 
> ejection wadding (cellulose insulation material) into the open 
> end of D-motors and covering it with a couple layers of masking 
> tape!  Tis sufficient to contain any flame from the motor and is 
> certainly a heck of a lot faster than epoxy!
> 

I once had an RC RG burn up in flight when that didnt work.. and I really
CRAMMED in the wadding, and used strapping tape.  At least the only damage
was to the model.

IMHO, an epoxy plug is MUCH safer than having a flaming model start a
grass fire.  If you are doing enough engines to do serious RC RG flying,
epoxy is faster.. I used to do 30+ motors at a time... took 10 seconds
each to pour in the epoxy,

Bob

-- 
*********************************************************************
*  Bob Parks                         You can surf the Net...        *
*  [email-masked]               or you can be the one          *
*  [email-masked]         making the waves.              *
*  (408) 253-0246                           D. Plotnikoff, 1995     *
*********************************************************************

Article: 19867 of rec.models.rockets
From: Greg Glenn x1879 <glenn>
Subject: New Rocket Shop in Phoenix -  Greg Glenn
Date: Wed, 11 Oct 1995 16:36:14 GMT
Message-ID: <[email-masked]>
Lines: 5

Any rocketeers living in the Phoenix AZ metro area should check out 
Atomic Rockets.  I don't have the exact address, but they are on 32nd Street
just south of Shea Blvd, phone 602-404-1663.   They have kits (PML, AeroTech,
Quest, etc) components for low and high power , and LOTS of motors in stock.

Article: 19868 of rec.models.rockets
From: [email-masked] (Walt Rosenberg)
Subject: Re: What causes "chuffing" *exactly?
Message-ID: <[email-masked]>
References: <[email-masked]> <mgreenl.813005354@hubcap>
Date: Wed, 11 Oct 1995 19:12:25 GMT
Lines: 33

In article <mgreenl.813005354@hubcap> [email-masked] (Matthew S Greenlaw) writes:
>[email-masked] writes:
>
>>	Dear rocketeers, 
>
>>Please describe in the finest detail possible, what exactly causes the
>>chuffing effect? If I were to WANT to have my rocket to CHUFF what would 
>>I need to do?
>>Ignition temperature, initial pressure, compositions, nozzle throat 
>>diameter? A fuel with a high pressure exponent? Shape of fuel pellet
>
>Now, correct if I am wrong (Paul Gennrich esp :) ), but a chuff usually
>occurs only in Vulcan motors or Smokey Sam (Black Jack) motor compositions.
>
>Second, most motors that chuff are Smokey Sam compositions (or something
>similar that puts out black smoke). The reason Smokey Sam motors leave
>black contrails is that they have a very inefficient burn.  They burn on
>the "rich" side--spewing raw fuel out the nozzle.  This tends to make ignition
>difficult; sometimes the motor will start, and then go out [chuff] and then
>quickly reignite. Sometimes they do not reignite and you have to go out there

I have a hard time believeing this.  I thought the black smoke was the
result of the combustion of Zn in the formulation and not a "rich" mixture. 
I think the "rich" mixture theory is more appropriate to internal combustion
(piston type) engines.

Walt

-- 
[email-masked]  TRA# 1448
LDRS and Fireballs was GREAT!!!!!  The best ever launch that I have ever
attended.  A new standard was established!  Great job AERO-PAC!

Article: 19869 of rec.models.rockets
From: [email-masked] (Russell Durkee)
Subject: Re: Kid groups for Rocktrey
Date: Wed, 11 Oct 1995 20:44:01 GMT
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

Thanks for covering me Jonathan!  I was out of town recently
and have not been here for a while.

There is a Tripoli group in the twin cities area but I am not
familiar enough with that group to say if they work well or at
all with young people.   I on the other hand love doing that
sort of thing and I would be glad to help anyone in the TC
metro area.  During my stint with the CIA in Illinois I was involved
in numerous building sessions and other structured rocketry
activities for young people.  I would be happy to talk with any
of your students and direct them toward good local sources of
rocketry supplies or organize a launch or launches or give a 
demonstration....just give me a call!

Russ Durkee
[email-masked]
612-996-0401

Article: 19870 of rec.models.rockets
From: [email-masked] (Jonathan Sivier )
Subject: Re: A brief launch report, questions & comments
Date: 11 Oct 1995 21:54:23 GMT
Lines: 38
Message-ID: <[email-masked]>
References: <[email-masked]>  <[email-masked]> <[email-masked]>

[email-masked]  (Kevin Forsyth) writes:

>> >> One is silver mylar sheet, the kind of stuff they use in greenhouses 
>> (and party balloons). <<
>> 
> 
>The stuff I'm using was leftovers from a big roll (4 feet x 50') a friend 
>bought from an indoor gardening supply shop.  It's expensive this way... but 
>would give you a lifetime supply.  I'm not sure, but I tend to think 
>emergency blankets would be heavier, maybe too heavy.
> 
>I made a chute out of the stuff, but because I was paranoid about tearing I 
>reinforced it with scotch tape around the edges and across the middle (like 
>seams).  Unfortunately the tape made the chute stiff and after a couple of 
>flights it failed to open.  However, the mylar is not as prone to tearing as 
>I thought, if you only reinforce the corners where you attach the shroud 
>lines it should work well.  I'm betting party balloons would work great-- 
>plus they're already in a round shape, for an instant chute.

   Here's a tip for reinforcing the attachment of shroud lines to plastic
parachutes, commercial or home-made.  Get some of the plastic (mylar?)
reinforcement rings used on loose-leaf paper from an office supply store.  They
come in white and clear.  Put one on each side of the chute at the attachment
point and poke a hole through by the bottom inner edge.  Tie the shroud line
on like with the newer Estes chutes.  This makes a very strong connection, the
chute will rip before the shroud line comes off.

Jonathan

----------------------------------------------------------------------
|  Jonathan Sivier          |  Secretary, Central Illinois Aerospace |
|  [email-masked]        |  NAR #56437                            |
|  Flight Simulation Lab    |  Tripoli #1906                         |
|  Beckman Institute        |  Home Address:                         |
|  405 N. Mathews           |    5 The Summit                        |
|  Urbana, IL  61801        |    Champaign, IL 61820                 |
|  217/244-1923             |    217/359-8225                        |
----------------------------------------------------------------------

Article: 19871 of rec.models.rockets
From: [email-masked] (Iskandar Taib)
Subject: Re: Iron-on covering
Date: 11 Oct 1995 22:25:05 GMT
Lines: 58
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>,
Larry Klug  <[email-masked]> wrote:
>[email-masked] (Iskandar Taib) wrote:
>
>>Umm.. I don't think any paints do this. Most lose weight as the
>>solvents leave. Some do polymerize when exposed to air, and may indeed
>>absorb some oxygen, but I doubt its very much..

>This process was explained to me by my father who is a former research
>chemist for Hercules, Inc. specializing in cellulose and polymers.  He 
>said that paint does gain weight when it dries because solvent molecules 
>are replaced by chains of oxygen molecules.  And heck, he's my dad, he 
>wouldn't lie about this, what does he have to gain?

I guess it might be useful to figure out _which_ paints do this - I'm
sure a lot don't. Polyurethanes might, but I don't think
cellulose-based paints (i.e. dope) does.

>According to the RC people, dope and tissue is old technology that 
>really doesn't add much strength compared to a an iron-on covering.
>
>I have used dope and tissue in the past for light BGs, but now that I'm 
>doing far heavier RC models, I just can't see the point.  Iron on 
>covering is really easy and produces really excellent results.

>BTW, my Stratoblaster is in great shape and ready to launch with my 
>recently narrow banded futaba gear.  My modified flagship is awaiting 
>micro servos and final assembly - both models completely covered with 
>blue and silver Flitecoat.

Oh OK.. If you're talking about models the size of a Stratoblaster,
then the iron-ons would be OK. I thought you were talking about small
boost gliders. 

On the other hand - the S8E folk don't use iron-ons - the ones I've
seen all have vaccum bagged fiberglass/tissue/epoxy finishes over the
sheet balsa. Very light, and very strong.

Mind you, if you have solid (i.e. sheeted) surfaces rather than an
open framework, tissue/dope is perfectly adequate, and a lot lighter,
_and_ does add considerable strength. The iron-ons are most beneficial
on open frameworks. The CL Stunt folk wouldn't touch iron-ons - they
just look too plastic and are heavy.

-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: [email-masked] |    Frog is Frog ala Peach
Home page: http://bigwig.geology.indiana.edu/iskandar/isk2.html

Article: 19872 of rec.models.rockets
From: [email-masked] (Doug Holverson)
Subject: Re: Epoxy Setting (was:Re: Could someone help with my Phoenix c.p. ques
Message-ID: <84.307c4d48@axolotl>
Date: 11 Oct 95 07:32:55 CST
Lines: 18

MAB>
MAB> In article <[email-masked]>
MAB> [email-masked] (Mark Johnson) writes:
>
>At an air temp of 95 F, epoxy in a plastic cup gets hot enough when it sets
to

>cause first and second degree burns.

MAB> I've gotten 1st degree bruns several times from epoxy while it was
MAB> setting into the formof a fillet. That got DAMN hot!
MAB>

Jeeech! What kind of epoxy were you using?

-DGH_

Article: 19873 of rec.models.rockets
From: Justin Gleiter <[email-masked]>
Subject: Re: What causes "chuffing" *exactly?
Date: Wed, 11 Oct 95 19:56:32 PDT
Lines: 15
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, <[email-masked]> writes:

> I have a hard time believeing this.  I thought the black smoke was the
> result of the combustion of Zn in the formulation and not a "rich" mixture. 
> I think the "rich" mixture theory is more appropriate to internal combustion
> (piston type) engines.
> 
If the combustion of Zn would produce black smoke, then how come Zn/S rockets 
produce white smoke?  The addition of Zn creates a fuel rich atmosphere, and 
thus black smoke.  Black smoke can also be produced by some different ways 
besides adding Zinc to the fuel.

Justin

Article: 19875 of rec.models.rockets
From: [email-masked] (Gary Hughes)
Subject: Re: Jetex fuel comp, pt. II
Date: 12 Oct 1995 01:40:18 GMT
Lines: 22
Message-ID: <[email-masked]>
References: <[email-masked]>

In <[email-masked]>, [email-masked] (Michael Edelman) writes:
>I wonder what the catalyst is?  I suspect a metal oxide, but I don't
>have any further evidence. What color is pure guanidine nitrate?
>
No idea about the catalyst, but guanidine nitrate is colorless when pure
according to Handbook of Chemistry (Lange). I have an old Flying Models
with a lengthy article about Cmdr. Benson, of autogyro fame. Apparently
he developed the Jetex propellant but failed to patent it. The article
mentioned something about 'steam compressing' and GN is very soluble.

>It does sound like it would be simple enough to make pellets with my 
>benchtop arbor press. 
>
I've seen occasional mention of early model rocket type engines being
loaded with an arbor press. What IS an arbor press??

gary

/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
Gary Hughes                                          [email-masked]
Stargate Video Systems                Multimedia and Network Consulting
/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/

Article: 19876 of rec.models.rockets
From: [email-masked] (Tony Wayne)
Subject: Re: Streamer Recovery
Message-ID: <[email-masked]>
Date: Thu, 12 Oct 1995 01:35:24 GMT
References: <[email-masked]>
Lines: 9

The 1974 NAR tech review highlights a research project from MIT
around the effectiveness of streamer ratios.  It suggests a
ratio of 10:1 as being optimum.  This report is available from
NARTS.
-tony

---
Tony Wayne     	                              Those that can, do,
[email-masked]                          -those that understand, teach.

Article: 19877 of rec.models.rockets
From: [email-masked] (Tony Wayne)
Subject: Re: Teaching kids...
Message-ID: <[email-masked]>
Date: Thu, 12 Oct 1995 01:41:07 GMT
References: <Pine.SOL.3.91.951006122203.9819A-100000@iglou>
Lines: 10

I have written a book called "Teaching Science Through Model
Rocketry." The book contains over 300 pages of ideas,
background, tips, hints, labs, handouts, etc. It is $44.00
(including shipping). Send me e-mail if you want more
information.
-tony

---
Tony Wayne     	                              Those that can, do,
[email-masked]                          -those that understand, teach.

Article: 19878 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: LDRS XIV VIDEO!  TOO MUCH FLESH!
Date: 12 Oct 1995 05:37:36 GMT
Lines: 26
Message-ID: <[email-masked]>

Howdy Folks,

Well I have just viewed Ky's video tape of Fireballs 005 
and LDRS.  I must say that it was very interesting.
I'm not sure how to take Ky's wife smoking cigars and 
drinking beer in the tub while narrating parts of the video, but
it is interesting if you find those sorts of things 
interesting.

The video starts off with rockets blowing up and crashing into
the desert floor.  Thats cool.  Then we goto the flight line,
and watch the hobby flyers ... not too different from other 
videos.  Then we get to Ky's wife, taking a bubble bath and 
smoking.  Needless to say, I was totally shocked and embarrased.
You see I'm at work and was showing the video to co-workers.
They thought I was trying to slip a porno in on them :)

Well, all in all, its a decent video.  I give it a grade of 
B for overall cinemaphotography, and a A+ for creative talent.
Seeing Ky's wife in the tub was a pleasant digression from 
"ho hum" rocket videos of the past.  Way to go KY!!!!!!!

-- 
John Dunbar

Article: 19879 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: BAR stories  (was thermalite)
Date: 12 Oct 1995 06:11:31 GMT
Lines: 55
Message-ID: <[email-masked]>
References: <99.307a5077@axolotl>

    Talk about BARs!:) (Born Again Rocketeers) Tell me about those early days
    please because I missed them....

Ok.  Yesterday I was looking for something else, and happened to come across
an old issues of "Model Rocket News".  This is/was sort of the Estes rocket
club newletter, and includes space related news, plans (usually from "Design
of the month club" winners), and of course advertisments.

This issue is from July, 1973.

The cover story is about the Apollo-Soyuz project: "Current plans call for
a mid-1975 linkup of orbiting Apollo and Soyuz spacecraft. ..."

Inside is "Notes from Vern", speculating that the Astronauts on Skylab I
might have noticed Estes as they directed the Earth Resource Telecope
toward Colorado.

Thanks are plans for "Top Secret", a sort of neat-looking jet-styled rocket,
and "pencil rocket", a rather boring rocket with a nice paint scheme.

And the ads!  Sigh:

Exotic Designs:
   Star Blazer		$1.99
   Orbital Transport	$3.75
   Starship Vega	$4.75
   Interceptor (a whopping) $5.25
Sounding Rockets:
   Sandhawk		$3.00
   Aerobee 300		$2.00
   Arcas		$2.40
Military Vehicles:
   Mini-Bomarc		$2.49
   V-2			$2.75
   Honest John		$2.25
Also:
   Bandit (with ducted ejection!) $4.25

Of course, the apparently low price (I don't remember them seeming so
low at the time) don't tell the whole story!  On the minus side, there
was $0.45 handling charge on all orders less than $6, and postage ($.70
for up to a pound, $5.53 for 10 lbs!  (oops that's just "priority postage".
Normal postage was included.)

On the plus side, orders over $5 would give you a choice of a free
Birdie or Sprite, $10 an Apogee II or a nighthawk, and over $15 a
Cobra or Farside.

I actually still have my "Top Secret" that was built back then but never
launched, an orbital transport (my second, also never launched), an Honest
John (apparently my brothers, but I was BAR first and snagged it!), and a
Birdie (design modernized to use T motors.)  Nostaliga is a wonderful thing!

BillW

Article: 19880 of rec.models.rockets
From: [email-masked] (Wolfram v.Kiparsky)
Subject: Re: sunsite software
Date: Thu, 12 Oct 1995 01:22:30 -0500
Lines: 14
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, [email-masked] (Lee Reep) wrote:

> Our group uses RSIM, a far superior program for altitude prediction
> than the more commonly used, and known, RASP.  RSIM has a engine
> editor that is really easy to use.  I've added several newer Aerotech
> motors that were not modelled previously.  Try this with even any of
> the commercially sold programs.  I don't think any of them allow
> you to add new motor files on your own.

The Mac program, compuroc, allows the generation of new engine classes for
the software to use.  It doesn't do this in a very easy way, but it can be
done.  Compuroc is in need of some updating.

Wolfram

Article: 19881 of rec.models.rockets
From: [email-masked] (BRIAN ROBINSON)
Subject: Re: 5 minute epoxy
Message-ID: <[email-masked]>
Date: Wed, 11 Oct 95 20:48:00 -0800
References: <[email-masked]>
Lines: 11

WW| I saw DEVCON "1-minute" epoxy in the hardware store the other day.

Heh heh heh! It probably goes off while you're still stirring it!

  _______ _______ _______   __                            
 |    .  |    ___|    . _| |  |                  {o o}       W E L C O M E
 |    .  |    ___|       | |__|   ------------ooO-(_)-Ooo-   T O T H E N E
 |_______|_______|____|__| |__|   [email-masked]   X T L E V E L

 * RM 1.3 02952 * Old computers never die, they just become video games.

Article: 19882 of rec.models.rockets
From: [email-masked] (Bill Nelson)
Subject: Re: Fin Drag
Date: 12 Oct 1995 06:33:44 GMT
Lines: 28
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Onnie X. Granados ([email-masked]) wrote:

: 	Let it out a few feet, so you can see it's motion.  If you built 
: it correctly, it will fly nose first, parallel to the ground, and look 
: pretty stable, not moving side to side.

This is not necessarily a good test. For example, many stable rockets (if
started with the tail forward) will actually stay tail first under the
string test. Start it out nose first and it will stay nose first. Also,
some stable rockets will show as unstable under the string test. This is
more true will long rockets than the shorter ones.

: 	But if your CP is ahead of your CG, the rocket will be unstable 
: -- it may fly sideways, tail first, whatever.  Not a pretty sight.

See above.

: 	If it's behaving like that, there are two things you can do -- 
: change the CG forward by adding weight to the nose, or bring the CP 
: backwards by making the fins bigger.  It's usually easier to start by 
: adding a little weight to the nose.  But do what you will.

Adding a small amount of nose weight is best. The reason for this is
that increasing the size of the fins also moves the CG rearward, which
is NOT what you want to do. It can actually make matters worse - rather
than better.

Bill

Article: 19883 of rec.models.rockets
From: [email-masked] (AKhome)
Subject: Water Bottle Rocket
Date: 12 Oct 1995 03:36:34 -0400
Lines: 8
Message-ID: <[email-masked]>

     I am building a rocket out of a 2-liter pop bottle for a Physics
assignment.  I am using only water and 40psi. air for "propellant." The
object of this activity is to maximize air-time, not altitude.  Does
anyone have any ideas?  I was thinking about using a loose, large nosecone
with a 4' or larger parachute under it which SHOULD come off at apogee.

 Thanks
 AlexK

Article: 19884 of rec.models.rockets
From: Andrew Broderick <[email-masked]>
Subject: Re: N2O / Propane Rocket
Date: Mon, 9 Oct 1995 16:28:58 GMT
Lines: 12
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

LRocket ([email-masked]) wrote:
: I have built and fired a 700 lbf thrust LOX/propane engine which I found
: to have extremely good performance. I measured C* efficiencies in the mid

I think I speak for many when I say: great post, it's good to see liquid
rocket experimentation going on, especially by someone as knowledgeable as
yourself, and keep us posted on developments, especially when you plan to fly
this baby !

Andy B 

Article: 19885 of rec.models.rockets
From: [email-masked] (Jeffrey D. Stai)
Subject: Re: What causes "chuffing" *exactly?
Date: 12 Oct 1995 02:59:41 GMT
Lines: 20
Message-ID: <[email-masked]>
References: <[email-masked]>

In <[email-masked]> [email-masked] writes:

>	Dear rocketeers, 

>Please describe in the finest detail possible, what exactly causes the
>chuffing effect? If I were to WANT to have my rocket to CHUFF what would 
>I need to do?

Well, I would think a little before I *wanted* a rocket to chuff! I have
personally witnessed a chuffing rocket LEAVE THE PAD and hop around on its
fins before finally igniting and taking off at full speed, mercifully in
the vertical direction! I suggest standing back a bit, at least...

(and if you were wondering: yes, I have it on video tape!!!-)

jeff stai, ke6knf
[email-masked]

Article: 19886 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Water Bottle Rocket
Date: 12 Oct 1995 08:35:17 GMT
Lines: 27
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, AKhome ([email-masked]) 
says...
>
>     I am building a rocket out of a 2-liter pop bottle for a Physics
>assignment.  I am using only water and 40psi. air for "propellant." The
>object of this activity is to maximize air-time, not altitude.  Does
>anyone have any ideas?  I was thinking about using a loose, large 
nosecone
>with a 4' or larger parachute under it which SHOULD come off at apogee.
>

If you can get a sufficiently vertical launch to get a tailslide, you 
could drape the parachute >over< the nose cone -- rocket goes up, starts 
tailslide, parachute fills and assembly returns gently, and >slowly< to 
the ground.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19887 of rec.models.rockets
From: [email-masked]
Subject: Re: What causes "chuffing" *exactly?
Date: Wed, 11 Oct 95 20:36:33 PDT
Lines: 50
Message-ID: <[email-masked]>
References: <[email-masked]>

Silent Observer wrote:
> >[email-masked] writes:
> >
> >Now, correct if I am wrong (Paul Gennrich esp :) ), but a chuff usually

Duhh... Carefull what you delete. This is not what *I* wrote. I was the one who 
asked a question.

..
> I don't know anything about Vulcan motors, but I've seen several small 
> Aerotech expendable motors (24mm, E and F impulse) chuff.  On those 
> motors, it's quite spectacular, as well as >loud<, with the motor making 
> a loud SNAP, then a pause, then another, longer BRAAP, then another 
> pause, then (sometimes) still another short burn and pause, before 
> settling down to do its duty.

This seems like chuffing I meant. I forgot to mention the type of chuff I am 
looking for is repeatedly. Unlike a single "chuff" spewing out the igniter.

> My understanding is that this is usually caused by ignition at the rear 
> of a slot grain; the gas movement inside the motor does two things.  
> First, it tends to prevent the combustion from spreading to the full 
> normal burn area, thus causing the motor to underpressurize, reducing 
> the burn rate -- and second, it tends to "blow out" the burn at the 
> nozzle end of the grain; without burning propellant "upstream" of the 
> location blown out, the motor loses pressure due to reduction of burn 
> area.  After a short pause, residual surface heat, in the absence or 
> reduction of gas movement, reignites the burning surface, usually 
> spreading the burn front a bit further "upstream" in the process.  The 
> whole cycle may then repeat once or more.

Yes please, DO chuff. Chuff more than once. Because that is just what I am 
looking for. I would like to see if there is a composition and engine system 
which could triggers and sustain that oscillatory combustion. 

> The motors I've seen this on were all White Lightning propellant -- not 
> a terribly inefficient burn, nor an overly high rate exponent, as I 
> understand things.  It seems to be mainly due to ignition too near the 
> nozzle, especially prevalent in slot-grain motors in smaller sizes, 
> where the slot is narrow enough it may be hard to push that Copperhead 
> into it (or even to find it through that small nozzle throat).  Some 
> were expendable, some reloads, but all were difficult to get the 
> igniters into at full depth.

Does anyone know what kind of fuel system it is? Or is making your own rocket 
fuel outdated? (Don't say ........)

Pi-Rho

Article: 19888 of rec.models.rockets
From: [email-masked] (F Brennion)
Subject: Re: sunsite software
Date: 12 Oct 1995 05:28:12 -0400
Lines: 10
Message-ID: <[email-masked]>
References: <[email-masked]>

 [email-masked] (Lee Reep) wrote:

>> RSIM has a engine editor that is really easy to use.  I've added
several newer Aerotech motors that were not modelled previously.  Try this
with even any of
the commercially sold programs.  I don't think any of them allow you to
add new motor files on your own. <<

Rogers Aeroscience's ALT4 has a motor module that allows you to enter your
own motors.

Article: 19889 of rec.models.rockets
From: [email-masked] (BOBROWSKI)
Subject: PISTON LAUNCHERS
Date: 12 Oct 1995 06:36:27 -0400
Lines: 16
Message-ID: <[email-masked]>

Pardon this digression to what may not be HPR turf.
I am seeking information on the principle(s) and design(s) of piston
launchers.  Currently, my only source is an uncharacteristically weak
description and sketch in Stine's "Handbook".  I was looking for something
a little more in-depth.  This might also be worthwhile as an inclusion in
the rmr FAQs, as I don't recall this topic covered there.  Owing to my
lack of visualization skills, a .gif posted on the sunsite.unc.edu ftp
would be sincerely appreciated.

Besides a description of design and operation I would enjoy whatever
anyone can share in the way of their experiences, observations and
opinions of piston launchers; and, just so this question is not a total
waste of bandwidth, "Why not use upscaled pistons to launch HPR ?"  (Is
there something I'm missing, like, 'Real rocketeers don't do pistons'?)

[email-masked] (Larry)

Article: 19890 of rec.models.rockets
From: [email-masked] (BOBROWSKI)
Subject: Re: Rocket Fuels
Date: 12 Oct 1995 06:44:52 -0400
Lines: 2
Message-ID: <[email-masked]>
References: <joan.813111635@giaeb>

The components of model rocket motors are extremely cheap, compared to the
cost of a good plastic surgeon.

Article: 19891 of rec.models.rockets
From: louwers@stevin (Louwers)
Subject: Re: What causes "chuffing" *exactly?
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
Date: Thu, 12 Oct 1995 10:54:00 GMT
Lines: 25

Strange theory. 
Here's my explanation of chuffing:

Chuffing only occurs at low pressures and has to do with the coupling between
heatfeedback from the gas phase to the solid phase. 
At low pressures there is a low burning rate, and hence a broad thermal zone
in the solid phase. At these low pressures the heatfeedback from the gas
phase to the consensed phase is low, and it takes some time to ignite. The
propellant ignites after some time due to continues heating from the gas phase.
Because there is a broad thermal zone due to conduction in the solid phase, it 
keeps burning for some time. When it reaches the end of the preheated zone it
stops burning. Due to the hot gasses present the propellant heats up again,
till it ignites again, etc. 

Especially KP (KClO4) is famous for its chuffing behavior. At high pressures 
heatfeedback is larger and no problems of chuffing exist.

--
Jeroen Louwers  
[email-masked] / \
                   |N|
                   |E|
                   |R|
                  /|O|\
                 /_|_|_\

Article: 19892 of rec.models.rockets
From: [email-masked] (Ryan Woebkenberg)
Subject: Re: PISTON LAUNCHERS
Date: 12 Oct 1995 11:54:05 GMT
Lines: 17
Message-ID: <[email-masked]>
References: <[email-masked]>

AHHH!  PISTONS!  I sorta like em.  They do add performance when
done properly.... Addd crazyness when not.  They are sometimes hard
to get to work just right.  they are these mechanical things that need
the right tightness and stuff to properlly work....  Ofthen they 
are just a nusance... you also need to keep em clean.  When they do
work right, they have an unmistakable POP and wiz to em.  QCR sells 
a kit for em...  you may wish to just buy the kit, then learn how
 to make your own... Pistons are hard to ASCII.  I think the kit
is pretty cheap too.

-- Ryan "Chad can fly rc, really"  Woebkenberg

--------------------------------------------------------------------------
[email-masked]  NAR 49363  TRA 1253 AMA 544846 
Come to NARAM 38.  If you do, I will try and have some interesting crashes 
--------------------------------------------------------------------------

Article: 19893 of rec.models.rockets
From: [email-masked] (Michael Edelman)
Subject: Re: What causes "chuffing" *exactly?
Date: 12 Oct 1995 12:37:31 GMT
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]> <mgreenl.813005354@hubcap> <[email-masked]>

Walt Rosenberg ([email-masked]) wrote:
: In article <mgreenl.813005354@hubcap> [email-masked] (Matthew S Greenlaw) writes:
: >
: >Second, most motors that chuff are Smokey Sam compositions (or something
: >similar that puts out black smoke). The reason Smokey Sam motors leave
: >black contrails is that they have a very inefficient burn.  They burn on
: >the "rich" side--spewing raw fuel out the nozzle.  This tends to make ignition
: I have a hard time believeing this.  I thought the black smoke was the
: result of the combustion of Zn in the formulation and not a "rich" mixture. 
: I think the "rich" mixture theory is more appropriate to internal combustion
: (piston type) engines.

Solid fuel motors used in aerospace sometimes are formulated to burn a
bit on the "rich" side- i.e., an excess of fuel. This is done not to produce
smoke, but to shoft combustion products to less CO2 and more CO. CO,
being lighter, is accelerated faster and proiducers a bit more thrust.

--mike

Article: 19894 of rec.models.rockets
From: [email-masked] (Tom Savard)
Subject: Nichrome wire and reliable second stage ignition Q's
Date: 12 Oct 1995 13:12:33 GMT
Lines: 27
Message-ID: <[email-masked]>

A week ago, I read a post about wrapping Nichrome wire around the Copperhead
pyrogen to get a more reliable igniter. Where can I get some nichrome wire?
I've found it being sold from a high purity alloy company, but the price
seemed high:  $66 for 10 m of .5 mm diam.

If I new some of the popular uses for nichrome, I might be able to find it
locally. Any suggestions?

Another alloy wire that might work well as an iginiter and with a
resistivity 30% higher than Nichrome is Fecralloy, an Iron/Chromium blend.
It was cheaper than Nichrome in the high purity market. Has anybody used
this stuff?

I'm searching for a more reliable igniter because I'd like to start a second
stage AP engine in the D-G range without the use of Thermalite. Does an
electric match work for these smaller engines? Does the match require a
supplemental pyrogen like the Copperhead tip or Thermalite? Are matches
difficult to obtain (ie regulated)?

Thanks-
Tom Savard
NAR #60293
-- 
Tom Savard			  	(919) 660-2515
Optical Physics Group		    	[email-masked]
Duke University Physics Department	

Article: 19895 of rec.models.rockets
From: [email-masked] (Robert J. Kinder)
Subject: Re: Video camera fitted in rocket
Date: 12 Oct 1995 09:16:11 -0400
Lines: 11
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Trash ([email-masked]) wrote:
: [email-masked] (Trevor Finnie) wrote:
: >
: > Has anyone ever tried to put a video camera in a rocket? Where would you get
: > one that would withstand such high g-forces (somehow I don't think wacking a
[snip!]

Super Circuits catalog: http://www.scx.com/catalog.html

Complete line of miniature single-board CCD video cameras, TV trasmitters 
and accessories.

Article: 19896 of rec.models.rockets
From: [email-masked] (Jason L. Eckhardt)
Subject: alt prediction?
Date: 12 Oct 1995 08:38:05 -0500
Lines: 17
Message-ID: <[email-masked]>

Q1:
I'm a reborn rocketeer and I'm trying to figure out how to predict my rocket's
altitude. The Aerotech kits I've built are nice in that they give a very 
detailed list of engines and predicted altitudes on those engines. The loc/p
kit I built, however (ezi-65), just listed a few engines and nothing else. 
In fact, the weight of the rocket wasn't even mentioned. 
Is there a cookbook formula one can use to make the determination (maybe
ignoring some factors such as shape, smoothness of rocket)?

Q2:
I still launch a few of my old estes favorites from years ago. But now they
all see to keep wrinkling up on the body tube where the nose cone fits in. Do
I have my nose cones too snug or what? I don't remember them doing this when
I was younger, maybe the engines are different (these were C-D estes engines).

thanks, jason

Article: 19897 of rec.models.rockets
From: [email-masked] (Tommy Usher)
Subject: Re: Launch Report, Birmingham, AL
Date: 12 Oct 1995 13:41:09 GMT
Lines: 49
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>,
The Silent Observer <[email-masked]> wrote:

>There are three likely possibilities for the cause of this accident.
>First, you may have used an engine with a too-short delay (for that 
>particular combination of thrust, impulse, and rockets, anyway); this 
>would cause ejection to occur before apogee, at a much higher velocity 
>that is desirable, possibly overstressing the shock cord and causing a 
>separation.  This can also cause "zipper" damage to the tube, and "Estes 
>dents" when the nose cone snaps back and slams into the body tube.

I am beginning to suspect it was the delay.  This WAS a short delay engine
(Walmart does not offer a very wide selection...) and when I checked the
instruction sheet, it was not the C class engine that was recommended.  I 
will know next time....

>Second possibility is, as you surmised, a burnt shock cord.  While I'd 
>have pooh-poohed that idea 20 years ago, at least for a rocket on only 
>its fourth flight, Estes is apparently using much less robust shock 
>cords than they used to -- and making them too short, into the bargain.

This is very possible....but given the engine used, that seems the most 
likely problem.

>The third possiblity relates to the too-short Estes stock shock cords -- 
>which also contribute to "Estes dents".  If the ejection charge in the 
>motor was on the hot side, a too-short shock cord might part when the 
>nose cone came to the end of its leash at higher velocity than on 
>previous flights; this might have been happening gradually through the 
>previous three flights, unnoticed during ground inspections, and taken 
>its final turn on the C-engine flight.

Very possibly.  I did check everything, and it seemed secure.  Of course,
the actual stresses would have possibly been higher.

>I'd suggest using a longer (approximately three times body length) and 
>more robust (something like twice the weight of the original) shock cord 
>for a replacement.  I'd also suggest thinking about whether the 
>parachute might have ejected early, and if you think it did, try the 
>next longer delay on the next C flight.

Yes, I think it was clearly a delay problem.... When I replace the chute,
shock cord, and nose cone, I will have to get some better engines.

-- 
+----------------------------------------------------------------------------+
| Tommy Usher  No Frills Software | Lubarsky's Law of Cybernetic Entomology: |
| [email-masked]             | There's always one more bug.             |
+----------------------------------------------------------------------------+

Article: 19898 of rec.models.rockets
From: "Steve Gaucher Jr." <[email-masked]>
Subject: Re: Launch Report
Date: 12 Oct 1995 16:49:38 GMT
Lines: 47
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

Okay looks like it works...I'm back into medel rocketry after about a 
15
year hiatus. Since the beginning of September, I've built 5 Estes 
products and flown each of them at least twice. Here is a brief 
synopsis.

Estes Beta Test Vehicle: Flew 6 times on a variety of B engines I had. 
Didn't survive landings very well as the plastic fin unit fractured. 
Lost is on it's first flight with a c6-5. Forgot how much higher the 
old c's go. Great flight... straight up and almost straight down... 
Landed in the trees.

Estes SR-71 Blackbird: Enjoyed building this one and it looked great 
when finished- almost didn't want to fly it- but of course, I did. 
First flight was on a B of some sort and it was great, though not very 
high. Next flew it on c6-5s twice and it flew just fine although one 
of the stabilizers broke on a hard landing. the next launch attempt 
was not as successful. Upon ignition, the Blackbird rose about 40 feet 
and then nosed over to horizontal, apparently wanting to fly much like 
it's namesake. It was a beautiful sight too... right until it steve 
austined right into a light pole. Part of the ship actually landed in 
a trash can at the base of the pole... quite fitting. The most 
spectacular part had to be the parachute deployment as it sat in a 
heap on the ground. 
Post accident investigation revealed the nose weight had become 
dislodged in a previous landing ( a good guess I believe ). I'll have 
to build another one of those. 

Estes Pheonix: Great looking rocket, relatively easy to build. Has 
flown 3 times in D12-3's and has looked great. Seems to go higher than 
advertised but certainly no higher than 400'. Had to modify the base 
fins as they broke on the first flight but no it seems fine. Using a 
24" nylon chute for recovery. 

Estes Maniac: This one really gets attention but it's had some 
problems on its 3 flights. First flight the parachute snagged (D12-3) 
but it was recovered just 25 feet from launch site. Second flight the 
parachute ripped but again, it was recovered just a few feet away. 3rd 
flight the shock cord was severed- the body was recovered undamaged 
just a few feet away. However, we watched the nose cone drift for what 
seemed like 2 or 3 minutes until it settled into trees probably 1/2 
mile away. Still seeking a nose cone replacement. 

Also got an Estes Space Shuttle and flew it several times with limited 
success... might just leave that one as a display rocket....
Next time I fly or buy I'll post again. 

Article: 19899 of rec.models.rockets
From: [email-masked] (nal040700-Mckiou)
Subject: Re: US Spacemodeling Team Selection Results
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Date: Thu, 12 Oct 1995 19:19:08 GMT
Lines: 44

In article <[email-masked]>, David Klouser <[email-masked]> wrote:
>Kevin,
>
>I timed Dave O'Bryan, who maxed both the 1st and 2nd rounds.  He made 
>just a slight mistake in the third round...start to bring the model 
> down at 5 minutes for a >7 minute max.

I can understand why he did.  He told me in the first round he was
in very strong lift and did not have enough experience to get it down
fast.  The result was that his model simply disappeared into the
blue void, never to be seen again.  Expensive!

Both Dave and Ed LaCroix did very well.  Ed finished 4th, just 1 second
ahead of Dave.  If this trend keeps up, in a couple of years we
will significantly expand the number of active S8e pilots.  This is
really nice since 8 of the 12 team members who already fly S8e will
be able to compete in the S8e World Cup expected to be held at the 
1996 World Champs.  The US will probably have the largest team in 
the World Cup.

Sort of on another subject, one area where we really need more participation
on the US Spacemodeling Team is in Scale and Scale Altitude.  I know
there are many NAR scale modelers out there.  The number of people involved
in the scale events has not changed much in the last few years.  We 
certainly have two or three of the best scale modelers in the
world.  But, that's about where it ends.  Essentially anyone who put forth
an effort in Scale or Scale Atitude made the team.  I *was* glad to
see Ross Hironaka make the scale altitude team.  At least that expanded
by 1 the number of scale modelers.

Ohhh!  Here's an item of general interest.  Who says FAI
competition is boring <G>.  The 1996 WC will have a provisional
event called "Rocketplane" or "Starship" (S 11 P) competition.
This is a "scale" competition of rocketplanes or future starships
(past or present).  The French got this provisional event
accepted. They were flying these futuristic looking models at
the '94 WC in Poland.  One of them was huge.  This event should
be really fun to watch.   Hmmmm...I wonder if I could get a
Starship Enterprise to fly????   Oooooo...Launch it with a single
motor behind the saucer and then, in flight, kick in the warp drives
(two D3s).  Kewl..big <G>.

Kevin

Article: 19900 of rec.models.rockets
From: [email-masked] (Konrad Hambrick)
Subject: Re: Could someone help with my Phoenix c.p. question ???
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Date: Thu, 12 Oct 1995 15:16:02 GMT
Lines: 84

In article <[email-masked]>,
William  <[email-masked]> wrote:
>Can the "cardboard cutout" technique be generalized by having the rocket
>"cast its shadow" at multiple angles of attack, and ensuring that the cg
>of the projection (~Cp)is always behind of the cg of the actual model?
>
>Ought to be something a computer would be good at!
>
>It would be rather nice, cause I think it generalizes even further into
>asymetric fin configurations and such by rotating the model around all
>axis of non-symetry, right?
>
>You would have to have a mathematical model of what your rocket looked
>like, but after that standard computer graphics algorithms for projecting
>3d objects onto 2d planes would handle most of the work.
>

Bill --

I wondered the same thing when I wrote program profiler
to do the centroids of the projected area and the BEq's. 
Profiler works by taking data entered as cylindrical
coords and projects them onto a cartesian plane (y,z).
It would be simple to translate the entered data by first 
applying a shear equal to the angle of attack before the 
projection onto the y,z plane and I planned on doing so.
But here is what I have learned so far about the derivation
of the BEq's.

The BEq's incorporate the lift and moments of the various 
rocket components and they should work up to the stall angle 
or angle of zero-lift.  For example, a fin based upon an 
NACA 0006 airfoil ( the symetrical, uncambered, tear-drop 
shape where the max thickness is 6% of the chord length ) 
stalls at +/- 8 Deg.  Between these angles of zero-lift, 
the Cl ( which is the slope of the lift coefficient ) runs 
from -0.8 at -8 Deg, thru (0.0,0.0) to +0.8 at +8 Deg -- 
or 0.1 per degree alpha.

The pitching moment, measured 25% back from the leading
edge ( the 'quarter chord' ) is zero between -8 deg and
+8 deg.  Once the fin stalls, the moment increases for
negative angles and decreases for positive angles as a
parabola.  This means that the lift is concentrated at
the quarter chord between +/- 8 deg angle of attack ( the
CP of this fin is at the quarter chord ).  When the fin 
stalls, the center of pressure moves back along the chord 
and all bets are off.

Anyhow, the lift and the associated moments of the fins
would really complicate the problem as alpha approaches
0 deg angle of attack ( from 90 deg ) -- not to mention 
the effects of the nose and transitions.

I am trying to work this problem out so it can be factored
into an off-vertical altitude simulator but I have a
**long** way to go toward understanding stability enough
to include it in that program ( called overt (c) ;-).

>The info input into the current Barrowman programs ought to be sufficient
>to build the internal model.

Yes it would be.  One thing about program profiler is that
it calculates the BEq input from the (z,r) cylindrical
coords of the vertices of one of the fins.  I thought it 
would be easier to measure consistantly, given that the 
leading, root edge of the fin is (0,0) and each vertex is
measured as a distance back and a distance out from that
reference point.

>
>I don't know if it would handle tube-finned rockets (significant airflow
>in "hidden" areas), or surfaces that actually generate lift, however.
>

Me neither, but one thing at a time ;-)

-- kjh

-- 
------------------------------------------------------------
Konrad J. Hambrick           |  email:  [email-masked]  |   
310 Third Ave - Suite C21    |  work:   (619) 585 8611     |
Chula Vista, CA  91910       |  home:   (619) 423-4451     |

Article: 19901 of rec.models.rockets
From: "Steve Gaucher Jr." <[email-masked]>
Subject: Re: Launch Report
Date: 12 Oct 1995 16:19:36 GMT
Lines: 2
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Just trying to see if I can post some launch reports to this group....

Article: 19902 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Launch Report
Date: 12 Oct 1995 18:14:38 GMT
Lines: 22
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, Steve Gaucher 
Jr. ([email-masked]) says...
>
>Just trying to see if I can post some launch reports to this group....
>

Please do!  Just ignore the politics and flamewars -- we're really here 
to read and type about rockets.

B)

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19903 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: What causes "chuffing" *exactly?
Date: 12 Oct 1995 18:14:48 GMT
Lines: 81
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In article <[email-masked]>, 
[email-masked] ([email-masked]) 
says...
>
>
>Silent Observer wrote:
>>The 
>> whole cycle may then repeat once or more.
>
>Yes please, DO chuff. Chuff more than once. Because that is just what I 
am 
>looking for. I would like to see if there is a composition and engine 
system 
>which could triggers and sustain that oscillatory combustion. 
>

I don't know for sure how you'd start and sustain a chuff intentionally 
-- for rocketry, most of the effort goes into preventing chuffs, since 
they make for low-apogee flights which, with "proper" delays for the 
performance you expect from the motor, can lead to lawn-darts.

I can speculate, however, that what you probably want is some means of 
allowing repeated catastrophic depressurization of the motor, without 
preventing repressurization.

As a first approximately, some kind of spring-loaded nozzle or relief 
valve might allow this; the idea is, when the motor comes up to 
pressure, the nozzle throat "blows out" temporarily, as if you'd 
suddenly switched to a much larger nozzle; this will reduce the motor 
pressure suddenly.  It might put out the burn, and will surely slow it 
greatly; that would be the cue for the nozzle system to return to 
"normal" or even a little tight for the propellant used, so that the 
motor can relight from residual heat, or resume normal-rate burning as 
the pressure comes back up.

I can picture a nozzle spring-loaded so it slides in and out along a 
tube; when pushed out by pressure (and I do >not< know if the thrust 
generated would prevent this from working -- I'm not sure where, 
internal to the motor, the thrust is applied) the nozzle would uncover a 
set of ports feeding vents or additional nozzles that would provide 
additional exit for the combustion gasses.  If the nozzle has enough 
mass to oscillate, rather than seeking a steady state with the ports 
partially open, you might be able to at least simulate a chuff over a 
number of cycles.

Sounds like a lot of work to go to to get an effect, though -- you could 
probably get more of less the same thing with a core-burning grain cast 
in layers of different burning rates, equivalent to, say, Blue Thunder 
and Black Jack; the motor would pressurize while the BT burns, then when 
you get to the BJ on the same nozzle, the pressure would drop and the 
fire might nearly go out.  You might have to play with the layer 
thicknesses, and this kind of propellant grain would be neither cheap, 
nor tested for safety prior to the experiment.

>
>Does anyone know what kind of fuel system it is? Or is making your own 
rocket 
>fuel outdated? (Don't say ........)
>

These are ammonium perchlorate composite propellants, whether Blue 
Thunder, White Lightning, or Black Jack -- I think even Smoky Sam is an 
AP composite, with additives to make the smoke.  The differences are in 
what's there besides the oxidizer and the synthetic rubber binder/fuel. 
 Some might contain accelerants, retardants, smoke producers, different 
mixture ratios, and even other chemicals intended to affect the burn 
rate exponent (i.e., how much pressure affects the burn rate).

The exact formulae of the Aerotech propellants cited are most likely 
trade secrets.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19904 of rec.models.rockets
From: [email-masked] (x )
Subject: Re: Rocket Fuels
Date: 12 Oct 1995 18:16:47 GMT
Lines: 11
Message-ID: <[email-masked]>
References: <joan.813111635@giaeb> <[email-masked]>

In <[email-masked]> [email-masked] (BOBROWSKI)
writes: 
>
>The components of model rocket motors are extremely cheap, compared to
the
>cost of a good plastic surgeon.

I had no idea plastic surgeons could be used as rocket fuel. What
proportion of oxidizer to plastic surgeon do you use?

-Bob

Article: 19908 of rec.models.rockets
From: [email-masked] (Mark Jilson)
Subject: Re: Launch Report, Richmond, VA (family style!)
Date: 12 Oct 1995 19:31:21 GMT
Lines: 24
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, 
[email-masked] (PaulDiming) writes:

>BullPup           A8-3, 1st launch.  Not a high flier, but impressive!

>BullPup is a great display rocket as well as one that can actually fly! 
>....  Looks great.  Flew straight.  Apparently it's
>not a high flier on A motors.  But I hear a lot of folks like this
rocket.

I also really enjoy the BullPup.  Make a bottom stage for it out of BT20
and some oversized fins (I made mine almost rectangular).  Since there is 
no engine hook and a boat tail it stages very nicely with just scotch tape
to
hold the engines together.  I made the BT20 about 3/8" shorter than an
Estes
18mm engine.  C6-0 to C6-7 makes it a nice high flier.

-- 
Mark D. Jilson  - Digital Customer Support Center
                  Colorado Springs, Colorado

NAR #54156,  COSROCS -- In Thrust We Trust

Article: 19909 of rec.models.rockets
From: Justin Gleiter <[email-masked]>
Subject: Re: LDRS XIV VIDEO! TOO MUCH FLESH!
Date: Thu, 12 Oct 95 15:39:24 PDT
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, <[email-masked]> writes:

> The video starts off with rockets blowing up and crashing into
> the desert floor.  Thats cool.
Neat, if it isn't your rocket.  Was my K1100 powered 5.5" Standard ARM 
included?  It was blown to bits at 2000' from an airstart cato.(F104Sil)

  Then we goto the flight line,
> and watch the hobby flyers ... not too different from other 
> videos.  Then we get to Ky's wife, taking a bubble bath and 
> smoking.  Needless to say, I was totally shocked and embarrased.

Hmmmmm...Really?  What's this video rated?

Justin

Article: 19910 of rec.models.rockets
From: Lawrence Jared Baskett <[email-masked]>
Subject: Re: Camera Payload
Date: Thu, 12 Oct 1995 13:36:39 -0700
Lines: 32
Message-ID: <[email-masked]>
References: <[email-masked]>

	I decided to build a 35mm camera rocket when I flew my Aerotech 
Initiator once (my only rocket to be powered by anything over an E) and 
thought, "So what?"  I wanted it to DO something, not just go up and 
down.  So I bought another two feet of tube from Aerotech to use as a 
payload section, wired the electronic shutter of a cheapie 35mm camera 
to a circuit made with a 555 chip, cut a hole in the side of the payload 
tube for the camera to peer through, rigged up a parachute harness with 
some shock cord, and voila! I had my camera rocket.  Including the G 
motor reload casing, all of this cost about $120, which is a heck of a 
lot less than the $300 for which the Cotriss Observer sells, although the 
Cotriss kit is a 3 inch diameter true high power model.  Cotriss also 
sells a pre-wired Ricoh camera for use in scratchbuilt camera rockets for 
around $125, although I doubt that it would fit into the Initiator's 2.6 
inch diameter tube.
	To go into more detail about my own project, the timer circuit 
takes some knowledge about electronics to put together (I had some help 
from an electrical engineer friend).  Adept used to sell a camera 
timer, but they discontinued it.  My trigger for the timer circuit is 
simply a slip of paper tied to the launch pad and inserted into a clip 
that breaks the timer circuit.  On liftoff, the paper pulls out and the 
clip closes to complete the circuit.  The camera then starts taking 
pictures continuously once every two seconds.  While the rocket is 
ascending, the photos are blurry due to the speed, but as soon as the 
parachute opens you get a nice panoramic view.  The parachute harness 
runs in a ^ shape to each end of the payload section so that it falls 
sideways, allowing the wide-angle view.
	I don't have any drawings for this configuration as of yet,
but I plan to someday write up this project for Sport Rocketry.  It's
the cheapest way that I can come up with to get a 35mm camera to a
respectable altitude.

				-Larry Baskett

Article: 19911 of rec.models.rockets
From: Larry Klug <[email-masked]>
Subject: Re: Iron-on covering
Date: 12 Oct 1995 20:52:09 GMT
Lines: 12
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

Iskandar,

Your points are well taken.
I haven't thrown away my dope and tissue supplies.

So far I've built a strato and a flagship.  I am curious...

What is an "S8E"?

Larry Klug

Article: 19912 of rec.models.rockets
From: [email-masked] (March A. Briner)
Subject: Re: Tripoli  Membership
Date: 12 Oct 1995 16:49:59 -0400
Lines: 11
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> [email-masked] (DavidlB145) writes:
>I  renewed  my  membership  a  couple  of  months  ago  yet  have  heard 
>nothing  back.  Is  this  typical?

I'm thinking of sending e-mail to the TRA membership HQ to confirm that 
they got the renewal application I mailed them  1 1/2 weeks ago. I'll let 
you know how it all goes...

					Marc

Article: 19913 of rec.models.rockets
From: [email-masked] (Robert B. Sisk)
Subject: BATTLE PARK LAUNCH FINAL INFORMATION
Date: 12 Oct 1995 20:46:34 GMT
Lines: 52
Message-ID: <[email-masked]>

I have had a number of email requests for this information.  It is
being posted because several of the return email addreses bounced.
Everyone who requested the info by email should have it unless yours
was one of the bad addresses.

Bob
  Sisk
------------------------------------------------------------------------
CENTRAL VIRGINIA / TRIPOLI #25 
INVITES YOU TO ITS FALL INVITATIONAL ROCKET LAUNCH
AT BATTLE PARK, CULPEPER, VA.

Date: November 18-19, 1995
Time: 9 AM to 6 PM
Location: Battle Park Launch Site
FAA Wavier: 15,000 feet
Launch Fee $10.00 (covers both days) Spectators can watch for free

For Additional Information Call:
Mike Showalter (703) 547-2539
Sonny Thompson (804) 733-8500
email [email-masked]

We will need volunteers to man the pads as well as RSO, LCO, PAD MGR, etc..
As usual all workers will get a GOLD CARD. This card will allow you to 
go to the head of the launch lineö when you are flying. If interested contact
Sonny Thompson. Some vendors will be attending and selling at the field.

DIRECTIONS:

Take ROUTE 29 South (from the Washington DC area) or ROUTE 29 North (from
the Charlottesville, Va.) to Culpeper Va.  Stay on 29 by pass when you get
to Culpeper and look for the ROUTE 3 exit. Take the ROUTE 3 exit towards
FREDERICKSBURG.  VERY IMPORTANT! You will only be on ROUTE 3 for a short
distance (I do not remember the exact distance, maybe less than a mile).
Look for ROUTE 522 (should be a right turn).  Take ROUTE 522 for about
5-6 miles to the launch site.  ROUTE 522 actually runs through the
middle of the launch complex.  Look for a sign (usually small) and cars
out in the fields.  We usually launch from the field that will be on your
right, however, this depends upon several factors and may no be decided
until the morning of the launch, so look in both fields. Just about 2-3
miles before you get to the field you will pass by a horse show area. 

NOTE: It may be faster for some people to take Interstate 95 to Fredericksburg
Va. Where you can pick up Route 3 to Culpeper.  If you do this Route 522 will
be a left turn. If you go over Route 29 on your way into Culpeper the you just
missed Route 522 by about 0.5-1 mile.
-------------------------------------------------------------------------------
-- 
---------------------------------------------------------------------------
- Dr. Robert B. Sisk			      Internet: [email-masked] -
---------------------------------------------------------------------------

Article: 19914 of rec.models.rockets
From: [email-masked] (kingrat)
Subject: Re: LDRS XIV VIDEO! TOO MUCH FLESH!
Date: 12 Oct 1995 21:20:31 GMT
Lines: 27
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Justin Gleiter ([email-masked]) wrote:

: In article <[email-masked]>, <[email-masked]> writes:

: > The video starts off with rockets blowing up and crashing into
: > the desert floor.  Thats cool.
: Neat, if it isn't your rocket.  Was my K1100 powered 5.5" Standard ARM 
: included?  It was blown to bits at 2000' from an airstart cato.(F104Sil)

:   Then we goto the flight line,
: > and watch the hobby flyers ... not too different from other 
: > videos.  Then we get to Ky's wife, taking a bubble bath and 
: > smoking.  Needless to say, I was totally shocked and embarrased.

: Hmmmmm...Really?  What's this video rated?

: Justin

Yeah, what's it rated and where can I get a copy? Is she pretty? Do any 
rockets blow up in the bathtub? Is the bathtub out on the flight line? 
Hmmmmmm.... I'm doing video at Danville the 28th. Maybe I could round up 
a few gorgeous babes and boost (pun intended) my sales. *snicker*

Eric Specht 
Tripoli 1755

Article: 19915 of rec.models.rockets
From: [email-masked] (Ryan Woebkenberg)
Subject: Re: US Spacemodeling Team Selection Results
Date: 12 Oct 1995 21:32:00 GMT
Lines: 48
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>,
nal040700-Mckiou <[email-masked]> wrote:
>In article <[email-masked]>, David Klouser <[email-masked]> wrote:
>
>Sort of on another subject, one area where we really need more participation
>on the US Spacemodeling Team is in Scale and Scale Altitude.  I know
>there are many NAR scale modelers out there.  The number of people involved
>in the scale events has not changed much in the last few years.  We 
>certainly have two or three of the best scale modelers in the
>world.  But, that's about where it ends.  Essentially anyone who put forth
>an effort in Scale or Scale Atitude made the team.  I *was* glad to
>see Ross Hironaka make the scale altitude team.  At least that expanded
>by 1 the number of scale modelers.

I think some of that may be due to a bit of an intimidation factor.
It is pretty obvous that the US scale team is world class..  The NARAM
entrys from the Scale Team (IE George and Jay) usaully win in Team 
Division...... Plus one tends to freak out at the amount of
hours needed to build a Scale bird compared to a PD bird, not to belittle
a PD bird.  Maybee I will try out for Scale in 98...  of course my 
resumay is pretty weak....  Just ask Peter Alway.

>
>Ohhh!  Here's an item of general interest.  Who says FAI
>competition is boring <G>.  The 1996 WC will have a provisional
>event called "Rocketplane" or "Starship" (S 11 P) competition.
>This is a "scale" competition of rocketplanes or future starships
>(past or present).  The French got this provisional event
>accepted. They were flying these futuristic looking models at
>the '94 WC in Poland.  One of them was huge.  This event should
>be really fun to watch.   Hmmmm...I wonder if I could get a
>Starship Enterprise to fly????   Oooooo...Launch it with a single
>motor behind the saucer and then, in flight, kick in the warp drives
>(two D3s).  Kewl..big <G>.
>

The French must have had a bad cheess year or something.  This is just
gone too far.  Mabee we can piss off some people by adding this to NARAM
38!!!!

-- Ryan "Chad can fly rc, really"  Woebkenberg

--------------------------------------------------------------------------
[email-masked]  NAR 49363  TRA 1253 AMA 544846 
Come to NARAM 38.  If you do, I will try and have some interesting crashes 
--------------------------------------------------------------------------

Article: 19916 of rec.models.rockets
From: [email-masked] (David Perry)
Subject: 100k feet altitude attempt?
Date: 12 Oct 1995 21:39:47 GMT
Lines: 18
Message-ID: <[email-masked]>

I wonder if this is really possible.  I have a 27 kilo (54 lb.), 3 stage 
rocket, using Aerotech's (N9600 (1st)/ N3050 (2nd & 3rd stages)).  The 
rocket has a drag of Cd=.37  .   I ran many simulations using various 
programs, including Larry Cursio's latest, to test if this could be done.
Can someone tell me if these simulations are accurate or they are way off 
on reality?  If the later then could you imagine N clusters? We might 
even reach low-orbital altitudes!

Please reply soon, I want to start this project soon if it is a reality.

Rocketgoon man--------------dave !

--

David Perry
[email-masked]

Article: 19917 of rec.models.rockets
From: [email-masked] (James G Horner (transfered to HPL))
Subject: Re: Camera Payload
Date: 12 Oct 1995 22:28:19 GMT
Lines: 17
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Lawrence Jared Baskett ([email-masked]) wrote:

: pictures continuously once every two seconds.  While the rocket is 
: ascending, the photos are blurry due to the speed, but as soon as the 
: parachute opens you get a nice panoramic view.

Why don't you have the camera start taking pictures when the ejection
charge blows instead of at liftoff?  That way you won't get the blurry
shots. 

--
-------------------------------------------------------------------------
 Jim Horner, MS 26U-4                     Hewlett-Packard Laboratories
 High Speed Electronics Department        email: [email-masked]
 3500 Deer Creek Road                     Phone: 415-857-6185
 Palo Alto CA, 94304-1392                 Fax:   415-857-3637
-------------------------------------------------------------------------

Article: 19918 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: Re: Video camera fitted in rocket
Date: 13 Oct 1995 00:57:49 GMT
Lines: 30
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

Trash <[email-masked]> wrote:
>[email-masked] (Trevor Finnie) wrote:
>>
>> Has anyone ever tried to put a video camera in a rocket? Where would you get
>> one that would withstand such high g-forces (somehow I don't think wacking a
>> camcorder into a HPR would be very good for the camera ;-))? Anyway, it 
>> would be fun, so if you have any ideas please let me know!
>> 
>> Trev.
>> 
>
> CCD cameras can handle high G's quite well.  Check out an magazine
>called   73 Amateur Radio.     August 1990 issue #359
>
>It has lots of info on how to put television into your rocket.
>A UHF live downlink is used to retrieve your pictures.
>
> Most small rockets have problems with space. So a CCD camera and lens
>are mounted in the main body of the rocket facing upwards and using
>a mirror to look back down through a window. The results are nothing
>short of spectacular.
>
> - Trash
>

Send me your address and I'll mail you a catalog for video 
tv from rocket products.
-- 
John Dunbar

Article: 19919 of rec.models.rockets
From: "Mark W. Howe" <[email-masked]>
Subject: Review of the Rocketman "LDRS XIV" Video Tape
Date: 12 Oct 1995 23:52:59 GMT
Lines: 65
Message-ID: <[email-masked]>

I'm a YABAR and have been mostly a "lurker" in the R.M.R. newsgroup for
the past 6 months.  I have found the information posted in RMR to be
extremely valuable since my resurgence into this hobby 2 years ago,(I
took a "brief" leave of absence from 1975 to 1993).  My return to the
hobby was due to my eldest son, who at age three found some old unbuilt
kits in our basement and asked me about them.  When I told him what they
were...and what we could DO with them... he looked at me with a very
serious expression on his face and stated, "Daddy, we HAVE to do this"!
I built the kits, (an "AS Missle" and a "Big Bertha"), found my old
"Cherrokee-D", and we literally had a blast.  We were both hooked,(I
build and prep, he and his friends push the button).  Since that time
I've built over 60 models, but nothing more powerful than a triple "E"
cluster (Estes Maxi-Force).  However, I am digressing...I did not
originally intend to post my personal rocketry history.

Reading all the RMR threads related to HPR has really got me hungry for
more power.  I've never been to an HPR launch (I'm working on it...), 
so I thought a video would be the next best thing,(I know it can't
compare to actually being there).  With this in mind I recently purchased
the "LDRS XIV & FIREBALLS 005" video by "ROCKETMAN ENTERPRISES HIGH
THRUST VIDEOS" from Kevin Nolan at Countdown Hobbies for $19.99.  What
follows is a brief review of that video.  Note that this is the first HPR
rocket video I have ever watched, so I cannot make comparisons to
others...I'll have to leave that up to the "experts" in the field.

Video running time: 68 minutes

PROS:
The opening sequences of the video are excellant.  The prepping of Ky
Michaelson's "D.R. HERO" was interesting and it's (unfortunate)
subsequent destruction spectacular.  Awesome is the way I would describe
the crash of Chuck Sackett's "PROJECT 463".  I only wish there had been
some close ups of the rocket before launch to bring its' massive size
into perspective.  The pre-flight banter and women's record altitude
launch of Jodi Michaelson's "J.D. CRUISER" proves that she's not just a
pretty face, but intelligent and able to build one heck of a rocket!  I
must say those HPR birds really move.  The video action advances quickly
through many launches, and even included the launching of a Estes "C"
powered bird by a couple of youngsters (I could really relate to that!).
It was also nice to put faces with the names I have been reading
about on RMR, such as the Vaughn brothers.

CONS:
The audio during the brief dissertations by the various rocket builders
could have been boosted up a bit, sometimes it was hard to hear what they
were saying,(You could definitely hear the roar of the birds in the
background as they were talking, so maybe the volume was kept low for a
reason).  As mentioned above, I feel that more closeups would have been
nice as well.  Also, a number of rockets with their builders/owners were
shown, but you never got a chance to see those rockets launched, (I was
looking forward to seeing GODZILLA and the DCX blast off, but they were
not captured on tape).  Lastly, I thought the "Bedtime Story" ending was
rather campy in nature, but that's the directors prerogative.

All in all it was a fine tape, and my thirst for HPR is now starting to
overwhelm me!  I would like to solicit the opinions of others after they
have viewed the tape. 

Best Regards,
Mark W. Howe
"Eschew Obfuscation"

Article: 19920 of rec.models.rockets
From: [email-masked](Paul Hamilton)
Subject: Long, boring historical essay
Date: 13 Oct 1995 01:50:59 GMT
Lines: 130
Message-ID: <[email-masked]>

                      Model Rocketry in the 1950's and 1960's 
 
How it all began 
 
The model rocket industry started with Model Missiles, Inc,.in 1958. 
Interestingly, Model Missiles sold what amounted to a "starter set" -- 
they would sell you engines, a kit for an Aerobee-Hi, and a launch stand. 
The first engines were generally quite similar to modern ones.  They were
11/16 of an inch in diameter and a little shorter than the present 2.75
inches.  The case material seemed to be some sort of resin or plastic
impregnated material.  It was definitely not the modern rolled paper tube. 
There was a green wrapper which was mostly hidden by the white paper label
which covered 
most of the motor.  They became the "A" engine.   In modern terms, they
were probably an A4-3. They were made in small lots, using shotgun
reloading equipment.  Ignition was with Jetex fuse, bent into a narrow "V"
and inserted into the nozzle.  They started well with a car battery and
twenty 
feet of zip cord.  G. Harry Stine was the co-developer of the engines. 
They were given the name "Rock-A-Chute", and marketed through America's
Hobby Center, a large New York area mail order firm. 
 
The Aerobee would not look out of place next to a modern model rocket.  It
was quite heavy -- about 1.5 ounces if I recall correctly.  Performance was
about 300 feet or so.  The body tube was a parallel wound paper tube, the
nosecone lathe-turned pine, and the fins were balsa.  The shock cord was
model airplane rubber.    Later versions of the Aerobee kit had a plastic
nosecone, so the turned wood was obviously expensive to make. 
 
How it developed 
 
Model rocketry developed quickly in the 1950's and 60' s.  The most
important thing was that Stine wrote frequently for American Modeler
magazine.  American Modeler  was an excellent magazine which found its way
into drugstores in the smallest hamlets in the country.  Interestingly,
there was better national coverage of model rocketry back then.  Today, the
"mainstream" model magazines ignore it completely, and the only sources of
info are a few specialty magazines with very limited circulation. 
 
Early model rockets were conservatively designed.  The only method we knew
for checking center of pressure was the paper cutout method.  This led to
models being either lightweight, with monsterous fins, or heavy and
small-finned with lots of nose ballast.  Neither nose cones nor paper 
tubes were available commercially, so one made one's own.  (Given the
prices today, this is still a good idea.  Besides, rolling body tubes and
sanding nosecones to shape with a drill is fun and a good way to unwind
after a hard day.)  One interesting note concerns rocket slang -- it has
changed.  Early engines were overbuilt and never failed.  I never read the
word "CATO" untill last year, and had no idea what it meant.  The word that
was used was "APE" (Almost Perfect Experiment) which referred to the flight
behavior of an unstable rocket. 
 
The NAR appeared in 1960 or so.  It took a while for a twelve year old to
track them down and write, so I  "only" got to be NAR 928.  1961 brought
boost gliders, and a "new look" as we began to read aerodynamics books and
learn that blunt noses produced less drag than pointed ones at subsonic
speeds.  Fins got longer and more swept as we tried to minimize frontal
area, weight, and induced drag.  We had a lot to learn.  High powered
rocketry appeared at about the same time with the Coaster F engines of 16
and 40 pounds thrust.  Coaster engines had only about a three second time
delay so were best suited to heavy rockets or rockets with payloads.  They
were covered with light green paper, looked like dynamite, and had to be
shipped railway express.  They were big, smokey black powder rockets --
loud and impressive. 
 
Meanwhile, Model Missiles had evidently sold out to Estes.  Vernon Estes
had an automatic machine (dubbed "Mable") which could turn out motors far
more quickly and inexpensively.  I guess Estes bought out MMI after being
their subcontractor for a while, because the last MMI motors and the first
Estes motors looked identical except for the names stamped on them. The 
1960 Estes motor was identical in appearance to the modern ones.  Estes
began bringing out rocket kits -- the Astron Scout (a small, sturdy, tumble
recovery job in which the engine slid back, but did not eject) and the
Astron Alpha (I don't need to describe this one.) 
 
In those days, Estes catalogs were more technical and emphasized parts and
motors, rather than kits.  They had an amazing variety of nose cones, nylon
screws, contact paper for B/G elevons, NAR payload weights, and many other
things.  Estes was mail order only, and shipped motors three to a 11 inch
by 1 inch mailing tube.  Ignition was by nicrome wire and car battery.  For
a 
while, Estes marketed a battery launcher which used a nicrome element to
light a Jetex fuse inserted "firework style" into the engine.  This device
a) worked only in warm weather, b) often burned fins c) encouraged many
rocketeers just to light the fuse and run.  It didn't help our image. 
 
What was good about the "good old days" ? 
 
There was good national coverage through American Modeler and G. H. Stein. 
Prices were low.  I think about a dollar for three B8-6 motors.  The Estes
catalog was virtually a model rocket handbook in itself.  It offered a
better variety than today.  Best of all, the theory and practice of 
model rocketry was growing every year.  There was the adventure of a new
field.  I would say that the best period was about 1961 - 1968, but I'm
biased because that was when I was most active. 
 
What is good about today? 
 
Engines are available everywhere.  You even find them in toy stores.  No
more one or two week waits.  Personal computers are great for drag,
stability, and performance calculations.  In the old days, we started out
with very little theory.  Then, in the mid 60's - 70's, we had the theory,
but it often did not help us because a computer was required to do the
calculation.  (I remember all the university physics projects which had a
rocket simulation deck tucked in next to them.)  Finally, the 'Net allows
rapid dissemination of knowledge.  Estes finally has a self-contained
launcher that works well (although cost considerations cause me to stick to
my zip cord and car battery).  I should also mention cyanoacrylate glue. 
 
What do you think would help the hobby? 
 
I get the feeling that rocketry has kind of stagnated in terms of growth
and activity.  (Compared to model aviation, which has really shrunk except
for high-end R/C, this really isn't doing too badly).  I 
think it would be a good idea to find someone to do a rocket column in
Flying Models.  Model aircraft and rocket folk have much in common and both
hobbies could be helped by bringing the two groups together.  The early
NARAMS had proxy entries.  You mailed them your rocket and they prepped and
flew it for a small entry fee.  This gave people far from major cities a
chance to take part in competition flying.  I wish we had that today. 
Finally, I've learned a lot by reading RMR -- I think this group is really
great. 
 
It is amazing how little the hobby has really changed.  You could come out
for a launch with 1965 motors, engine, and accessories and nobody would
ever notice.   It is something of a disappointment that there has been so
little progress in some  ways.  The good side of this is that the enjoyment
of flying a rocket is one of these things that have not changed.  On a nice
sunny day with light winds, does anything else really matter? 

Article: 19921 of rec.models.rockets
From: [email-masked] (Pierre Kerr)
Subject: Re: Water Bottle Rocket
Message-ID: <[email-masked]>
References:  <[email-masked]>
Date: Fri, 13 Oct 1995 03:35:53 GMT
Lines: 33

AKhome ([email-masked]) writes:
>      I am building a rocket out of a 2-liter pop bottle for a Physics
> assignment.  I am using only water and 40psi. air for "propellant." The
> object of this activity is to maximize air-time, not altitude.  Does
> anyone have any ideas?  I was thinking about using a loose, large nosecone
> with a 4' or larger parachute under it which SHOULD come off at apogee.
> 
>  Thanks
>  AlexK

I've tried a few things, not so much to maximize air-time, but to prevent
hard crashes.  The simplest has been to have an arm pivot from near the
nose.  The end of the arm has a fin that while in flight is held back with
the air pressure.  Once the speed reduces, an elastic will provide the
force to make this arm flip out to the side and cause the rocket to spin
slowly back to Earth.  My problems have been making a pivot hold the arm
solidly when extended out, and yet survive the fall.  If the rocket
happens to fall on the arm, it usually snaps something. 

I posted a question here about 6 months ago asking for ideas for recovery
systems and someone mentioned a commercially sold water or some kind of
gas pressure rocket that had a nose cone that was held by  rubber which,
when the rocket was presurized, pushed out to hold the nose on.  When the
pressure was gone the nose was pushed off with a spring and a chute
deployed.  Sounds good, but not easy to make with a glue gun and pop bottle.

Good luck

--
Pierre A. Kerr                                <>
   Someone once told me to "go fly a kite",  /  ~~
   so I did, and I liked it.               /

Article: 19922 of rec.models.rockets
From: Lawrence Jared Baskett <[email-masked]>
Subject: Re: Camera Payload
Date: Thu, 12 Oct 1995 21:17:46 -0700
Lines: 23
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

On 12 Oct 1995, James G Horner wrote:

> Lawrence Jared Baskett ([email-masked]) wrote:
> 
> : pictures continuously once every two seconds.  While the rocket is 
> : ascending, the photos are blurry due to the speed, but as soon as the 
> : parachute opens you get a nice panoramic view.
> 
> Why don't you have the camera start taking pictures when the ejection
> charge blows instead of at liftoff?  That way you won't get the blurry
> shots. 
> 
> --
	You're right, I could just have the paper slip pull out of the 
trigger clip on ejection, but my clip is not very tight and the paper 
slip would stand a good chance of being blown out by the airflow.
Seeing the sequential shots of blurred ground falling away is kind 
of cool anyway:), plus it lets me analyze the rocket's roll as it 
ascends.  After all, what are a few frames out of a roll of 36?
	If you want to have all of your photos come out as nice, clear 
panoramas, then the trigger-upon-ejection method is a good idea.

				-Larry Baskett

Article: 19923 of rec.models.rockets
From: [email-masked] (William )
Subject: Re: Launch Report, Birmingham, AL
Date: 13 Oct 1995 06:07:03 GMT
Lines: 12
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>
	<[email-masked]>

    (Walmart does not offer a very wide selection...)

My wife has a grudge against "Michael's Crafts", because the bought out Lee
Wards, which was better for the sorts of crafts she is into.  To give credit
where it is due, however, Michael's has a better (broader) selection of both
Estes Rockets AND motors than most of the "mass market" stores.  They run a
coupon ever couple weeks (so it seems) for 40% or 50% off anything (one
item) in the store, on a particular day (and particular hours.)  Could be
a good deal...

BillW

Article: 19924 of rec.models.rockets
From: [email-masked] (William )
Subject: Yet more cheap tricks: Tube peeling...
Date: 13 Oct 1995 06:36:21 GMT
Lines: 51
Message-ID: <[email-masked]>

I've mentioned (relatively recently) various sources of "found tubing" that
can be used by the frugal to make model rockets, including the 38mm ID
plastic bag cores from Safeway produce departments, and 3 inch ID tubing
widely used as cores for all sorts of rolled paper and packaging products
like plastic wrapping (shrink wrap?) used for tying together boxes on
pallets and such.  Several people have mentioned having access to the cores
from plotter paper...

The problem with such tubes is usually that they are TOO tough.  With wall
thickness of an eighth of an inch or more, they can be so heavy that you
need an HPR motor to get low power performance.  While this might be cool
from the noise and smoke perspective, most of use would like the best
performance possible out of our models...

Enter "tube peeling"!  Most of these tubes are spiral wound heavy craft
paper.  The technique is interesting - think of a narrow strip of paper
wound in a spiral on a rod WITHOUT overlapping.  Now apply some glue and
wind another strip offset by some fraction of the width so that it covers
the gap in the previous layer.  Repeat until the wall is as thick as you
want.  Since the seams don't show up in the same place, the tube is nearly
as strong as a parallel wound tube.

Anyway, the point is that you can REMOVE a couple of the layers, and wind up
with a thinner wall.  Since each layer is actually separate, it's pretty
easy to remove an integral number of layers so that the tube retains an even
thickness along its length, and you can tell when to stop.  The secret is
simply to get the outer layer of paper wet.  The glue used is usually both
water soluble and somewhat water resistant.  So the water soaks into the
outer layer, softening the paper and starting to soften the glue.  Then
you find a corner along one of the seams (that you'd normally fill with
putty of some kind to get a nice finish?) and simply unwrap the strip of
paper.  Usually some shreds will get left behind, but they're easy enough
to go back and peel off, or attack with sandpaper.  The combination of
the glues water resistance and the surface polish of the next layer will
tend to prevent it from getting too wet, so you get left with a pretty
nice and distinct surface for the next layer (and you can go hunting
for its seam as well.)  Repeat until the tube is the desired thickness.
(But don't get it TOO thin.  Remember that you need at least two layers
to have any stength at all!)

Last night I took about half the wall thickness off of a plotter paper core.
It's now about the same thickness as US Rockets' Heavy wall 3" tubing.

It's also possible to peel a tube from the inside, although this works
better with shorter tubes.

Near as I can tell from NARTS plans, competition modelers have been peeling
the outer layers from ESTES style tubing for some time, although it's not
clear whether that's been an advantage...

BillW

Article: 19925 of rec.models.rockets
From: [email-masked] (Jon Pike)
Subject: Thermalite timing...
Date: 13 Oct 1995 08:04:33 GMT
Lines: 16
Message-ID: <[email-masked]>

	Hello again..
I was wondering the aprox burning speed of Thermalite.. in its different 
classes (however many there are of those...).  How many inches/sec, that 
kind of thing.

	Also while we're at it.. what kind of delay do various rocket 
motors have in igniting?  Blackpowder C's and D's?  AP motors?  I'm 
looking to have a short delay (1-2 seconds, from flashbulb to engine on)
and am wondering what an inch of fuse or so will get me..

PS... someone please let me know if there is a faq on these subjects that 
I dont know about!

Thanks!

Jon

Article: 19926 of rec.models.rockets
From: [email-masked] (Smcello)
Subject: Re: 5 minute epoxy
Date: 13 Oct 1995 07:00:09 -0400
Lines: 15
Message-ID: <[email-masked]>
References: <[email-masked]>

What's the big problem with 5 minute epoxy? I used 5 minute Zpoxy (Pacer)
for the fillets on my Thoy Falcon. No problem flying that rocket on a
Kosdon 2550ns K1000, although the fins were heard to hum after motor
burn-out. On a Kosdon 2550ns K1700 the fins did come off at about 90%
through the thrust phase, but inspection of the debri showed the fillets
still attatched to the rocket. The fins had shredded off about 1/2 inch 
out from the body tube. maybe I'll try saturating the plywood fins with
thin CA next time around.

Steve "cardboard can go fast" Cello

PS: the debri was held together by 20 ft of clothes line running from the
foreward bulkhead of the motor to the electronics bay of the payload
section, allowing tumble recovery. Motor casing and electronics survived
the tumble from 800-1000ft agl.

Article: 19927 of rec.models.rockets
From: [email-masked] (Hank Eyring)
Subject: Rocketry greenie needs advice!
Date: Fri, 13 Oct 1995 01:54:10 GMT
Lines: 12
Message-ID: <[email-masked]>

I have been browsing various WWW pages and reading this newsgroup for
a while now.  I have had quite a bit of experience with your basic
department store variety of ESTES rockets.  I am 6'2'' tall and have a
rather strong urge to build one of these larger rockets that is taller
than me and spits out some fire and smoke before it rockets into the
wild blue yonder.  Anyone got advice as to where to start???
ie: kits, suppliers, books, magazines, etc  (I'm in Phoenix AZ area)

**** Phoenix SUNS will reign supreme in 96! ****
 **** Hank Eyring - Chandler, AZ - SUNS!  ****

Article: 19928 of rec.models.rockets
From: [email-masked] (David P. Dpahr)
Subject: re: Rocket Fuels
Date: Fri, 13 Oct 1995 07:34:41 GMT
Lines: 62
Message-ID: <[email-masked]>

If a outsider may inject a 'few' words about the use of Zinc and
Sulphur  as a propellant.

Back in the early 1950s, the Pacific Rocket Society's  Cal Tech
chapter did some work with the combination. They found that 
by segmenting the total charge they got more reliable and
consistant operation.

What they did was to make propellant packets from heavy
cardboard tubing , tissue paper and the Zinc/Sulphur  mixture.
Similar to the powder bags that the Navy uses in their large
caliber guns.

A cardboard tube, with an O.D. that would just slip into the aluminum
motor tube and  1\8  or 1\4 inch wall thickness, was cut into approx 
3 inch lengths and one end was sealed with a sheet of tissue paper and
the excess paper trimmed. After the glue had dried, a measured amount 
of the Zinc/Sulphur mixture was put into the tube segment and the open

end was sealed with another piece of tissue paper and the paper again,
trimmed.

When the rocket was to be fueled, all that was required was to slip
the packets into the motor tube and close it up. I don't recall if the
nozzel was tight against the bottom packet or if they had a spacer
in place. For firing, an igniter was placed against the bottom face of
the bottom packet.

This method of loading the motor has several advantages:
 1. It didn't require trying to pour a large quantity of the mixture

     into the motor tube. 
 2. The powder density was constant throughout the length of
     the motor, therefore combustion was more uniform, throughout
     the burn.
 3.  As the bottom powder burned, the possibility of the upper
     mixture trying to move into the lower part of the motor, via
    the mixtures own weight and acceleration was reduced.
 4. As the propellant burned, the 'chamber pressure' had less chance
    of trying to pack the mixture ahead of the flame front.

I wasn't a member of the PRS. I was a member of a student chapter
of the old American Rocket Society. in the mid-50s. One of our
grad-student members, David G. Elliot, had been a member of the PRS
when he was an undergrad at Cal Tech,. Dave gave a film resentation of
some of the Zinc/Sulphur work he had done with the PRS. He also showed

some film of a Hydrogen-Peroxide rocket that they had tried and lost
when it shed  its fins , they guessed, going through Mach-1. This one 
employed a booster and was aerodynamically tested in one of Cal Techs 
wind tunnels. 

I don't know if the PRS left any papers regarding their work with
 Cal Tech. If someone has access to Cal Tech's archieves they might
find something.

Sorry about the length, but I thought the information might be of 
interest.

David P. Spahr
[email-masked]

Article: 19929 of rec.models.rockets
From: [email-masked] (Patrick Frazer)
Subject: Re: Wiring an Adept Altimeter on a PML
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>
Date: Fri, 13 Oct 1995 13:40:49 GMT
Lines: 56

In article <[email-masked]>, [email-masked] (William ) writes:
|> Speaking of ejections charges, can you put the ejection charge of a
|> moderately sized rocket AHEAD of the parachute?  (requiring the separatation
|> to drag it out by the shock cord.)  That stage coupler (3" by 6" in a 3"
|> rocket) is an awfully tempting spot to mount electronics and ejection
|> charges.
|> 
|> 	 PAY
|> 	 LOAD                            PAY
|>         [_____]   	How about:       LOAD
|>         [| A |]   		        [_____] 
|>         [| A |]   		        [|A E|]   A == Altimiter
|>         [| A |]   		        [|A E|]   E == Ejection charge
|>          |   | Coupler	        [|A E|]  	(in tube) 
|>          |E  |    		         |--E|    Coupler
|>          |E  |    		         |CCC|  
|>         [ E   ]   		         |CCC|    C == Chute
|>         [     ]   		        [     ] 
|>         [     ]   		        [     ] 
|>         [ CCC ]   		        [     ] 
|>         [ CCC ]   		        [     ] 
|>         [     ]   		        [     ] 
|>                   		        [     ] 
|> 				                
|> 
|> In both case, I'm worried about the ejection charge blowing the chute
|> deep down into the body tube where it won't get pulled out.

How about something like this?  Extend the tube containing the ejection
charge so that it ends _below_ the chute.  The charge would have a
tendancy to push the chute into the coupler, not the body.  (Might
also be less likely to damage the chute)  However, you obviously need
a way to make sure the chute is pulled from the coupler.  This is
left as an exercise for the reader.  <grin>

[_____]
[|A E|]
[|A E|]
[|A E|]
 |A E|
 |--E|
 |CCE|
 |CCE|
 |CCE|
[     ]
[     ]
[     ]
[     ]

-Patrick

-----------------
Patrick M. Frazer                    [email-masked]
Systems & Security Admin             http://www.beacon.com/~frazer/
Beacon Graphics Corporation          419 289 0558 VOX  289 8923 FAX

Article: 19930 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: re: Rocket Fuels
Date: 13 Oct 1995 17:26:35 GMT
Lines: 39
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, David P. Dpahr 
([email-masked]) says...
>
>Back in the early 1950s, the Pacific Rocket Society's  Cal Tech
>chapter did some work with the combination. They found that 
>by segmenting the total charge they got more reliable and
>consistant operation.
>
>What they did was to make propellant packets from heavy
>cardboard tubing , tissue paper and the Zinc/Sulphur  mixture.
>Similar to the powder bags that the Navy uses in their large
>caliber guns.
>

<snip>

This method was touched on briefly in Brinley's book (not the best 
source, but some useful information, if you can figure out what's good 
and what's crap).  I see two major questions, mainly about >why< it 
works, assuming it does.

First, how does a tissue "bulkhead" keep several pounds of powder from 
shifting under a couple hundred Gs?  Second, related, how does a tissue 
bulkhead keep chamber pressure of a couple thousand psi from blowing 
through to pack the powder forward ahead of the combustion front?

In other words, it seems a sensible method, but I wonder if tissue paper 
is strong enough.  Has anyone else tried this method?

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19931 of rec.models.rockets
From: [email-masked] (Thomas Vandemerkt )
Subject: Re: Launch Report, Richmond, VA (family style!)
Date: 13 Oct 1995 14:46:55 GMT
Lines: 35
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]>

In <[email-masked]> [email-masked] (Mark 
Jilson) writes: 

>
>
>In article <[email-masked]>, 
>[email-masked] (PaulDiming) writes:
>
>>BullPup           A8-3, 1st launch.  Not a high flier, but impressive!
>
>>BullPup is a great display rocket as well as one that can actually 
fly! 
>>....  Looks great.  Flew straight.  Apparently it's
>>not a high flier on A motors.  But I hear a lot of folks like this
>rocket.
>
>I also really enjoy the BullPup.  Make a bottom stage for it out of 
BT20
>and some oversized fins (I made mine almost rectangular).  Since there 
is 
>no engine hook and a boat tail it stages very nicely with just scotch 
tape
>to
>hold the engines together.  I made the BT20 about 3/8" shorter than an
>Estes
>18mm engine.  C6-0 to C6-7 makes it a nice high flier.
>
>-- 
>Mark D. Jilson  - Digital Customer Support Center
>                  Colorado Springs, Colorado
>
>NAR #54156,  COSROCS -- In Thrust We Trust
>

It makes a cool lookin' dummy upper stage, too!

Article: 19932 of rec.models.rockets
From: [email-masked] (March A. Briner)
Subject: Re: alt prediction?
Date: 13 Oct 1995 13:26:29 -0400
Lines: 34
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> [email-masked] (Jason L. Eckhardt) writes:
>Q1:
>The loc/p kit I built, however (ezi-65), just listed a few engines and 
>nothing else. In fact, the weight of the rocket wasn't even mentioned. 
>Is there a cookbook formula one can use to make the determination (maybe
>ignoring some factors such as shape, smoothness of rocket)?

Yes, there is. All you'd need to know is the average thrust of the motor 
(given in the motor's designation in Newtons), the weight of the rocket 
(I believe an EZI-65 comes out to be something like 36 to 38 oz...that's 
what mine weighed anyway), and some very basic division. Divide the 
thrust of the motor by the weight of the rocket (get both numbers in the 
same units, of course!), and if the number comes out to be 3 or greater, 
you should be okay. In shorter terms, this is called a 3:1 thrust:weight 
ratio. 3:1 is the absolute minimum that you can get while still having a 
safe flight. I try to avoid such a low ratio myself...

>Q2:
>I still launch a few of my old estes favorites from years ago. But now they
>all see to keep wrinkling up on the body tube where the nose cone fits in. Do
>I have my nose cones too snug or what? 

Not sure what to tell you there. But then, I'm having a bit of a hard 
time picturing it. Sorry...

******************************************************************************

	Marc Briner		    *		nin    ei nc hn    ail
   Plymouth State College	    *		sn in  ei nc ch  ai ls
       New Hampshire		    *		ni  ne in ch na il  sn
   Live, Freeze, and DIE!	    *		in    ein ch nai    ls

******************************************************************************

Article: 19933 of rec.models.rockets
From: [email-masked] (March A. Briner)
Subject: Re: LDRS XIV VIDEO!  TOO MUCH FLESH!
Date: 13 Oct 1995 13:30:20 -0400
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]> John Dunbar <[email-masked]> writes:
>Howdy Folks,
>
>I'm not sure how to take Ky's wife smoking cigars and 
>drinking beer in the tub while narrating parts of the video, but
>it is interesting if you find those sorts of things 
>interesting.
>
>Then we get to Ky's wife, taking a bubble bath and 
>smoking.  Needless to say, I was totally shocked and embarrased.
>
>Seeing Ky's wife in the tub was a pleasant digression from 
>"ho hum" rocket videos of the past.  Way to go KY!!!!!!!

Hmm...wonder if Cagle's video has such material in it...

					Marc

Article: 19934 of rec.models.rockets
From: [email-masked] (Michael Park)
Subject: Re: Launch Report Questions
Date: 13 Oct 1995 15:24:08 GMT
Lines: 9
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

[email-masked] (Lee Reep) writes:
...
>This is America!
...

No, this is the net.

--m

Article: 19935 of rec.models.rockets
From: [email-masked]  (Kevin Forsyth)
Subject: Wanted: plans for Centuri SAM-5
Date: Fri, 13 Oct 1995  13:24 EDT
Lines: 16
Message-ID: <[email-masked]>

The Centuri SAM-5 model, a BT-20 version of a Russian ICBM, was the last
rocket I tried to build before my hiatus from rocketry.  At 11 I didn't 
understand the need for running balsa grain along the leading edge, and when
I discovered my mistake I got discouraged and gave up.
 
Somehow in the intervening 15 years the rocket has vanished from my parents'
house.  Anyone have a copy of the original plans so I can reconstruct one?
 
/kevin
---------------------------------------------------------------------------
 Kevin S. Forsyth, Programmer/Analyst
 Political Science Dept./School of Labor & Ind. Relations
 College of Social Science, Michigan State University
 226 South Kedzie Hall                    email: [email-masked]
 East Lansing, MI.  48824-1032            phone: (517) 353-8481
---------------------------------------------------------------------------

Article: 19936 of rec.models.rockets
From: [email-masked] (Matthew S Greenlaw)
Subject: Re: What causes "chuffing" *exactly?
Date: 12 Oct 95 14:59:47 GMT
Lines: 29
Message-ID: <mgreenl.813509987@hubcap>
References: <[email-masked]> <[email-masked]>

Justin Gleiter <[email-masked]> writes:

>> I have a hard time believeing this.  I thought the black smoke was the
>> result of the combustion of Zn in the formulation and not a "rich" mixture. 
>> I think the "rich" mixture theory is more appropriate to internal combustion
>> (piston type) engines.
>> 

I posted the original reply to the question about "chuffing". My term for 
describing the combustion as rich was a relative term.  All chemical reactions
occur in certain proportions, including combustion. In an internal combustion
engine, fuel (gasoline) is mixed air (oxidizer) in the carburetor and then
combusted. The terms "rich" or "lean" are used to describe the divergence
of the mixture from the optimal mix. Hence, rich describing too much fuel in
the mixture and lean describing too much air in the mixture.
   If a motor manufacturer puts too much fuel in a mixture, the excess fuel
will not react (burn, combust), but be throw out as a waste product. In the 
same way a car with a rich fuel mixture will have a very strong smell of
gasoline in the exhaust (raw, unburned fuel exiting with the exhaust). 
   So, If there is too much fuel in the mixture (or not enough oxidizer to
fully combust all the fuel present), it will be wasted out the nozzleœ' of the
motor as unused reactant.  Hope this clears it up.

-- 
Matthew Greenlaw        |  Is 40:31 - "They shall mount up with wings
[email-masked]     |              as eagles..."     
Mechanical Engineering  |---------------------------------------------
Clemson, S. Carolina    |  http://Hubcap.Clemson.Edu/~Mgreenl 

Article: 19937 of rec.models.rockets
From: [email-masked] (Jeff Pleimling)
Subject: Re: BAR stories  (was thermalite)
Date: Fri, 13 Oct 95 10:49:17 GMT
Lines: 51
Message-ID: <[email-masked]>
References: <99.307a5077@axolotl> <[email-masked]>

In article <[email-masked]>,
   [email-masked] (William ) wrote:
>    Talk about BARs!:) (Born Again Rocketeers) Tell me about those early days
>    please because I missed them....
>
> Ok.  Yesterday I was looking for something else, and happened to come across
> an old issues of "Model Rocket News".  This is/was sort of the Estes rocket
> club newletter, and includes space related news, plans (usually from "Design
> of the month club" winners), and of course advertisments.
>
> This issue is from July, 1973.

The only things I have left after my parents tossed most of my rocket stuff 
are a couple of engines (C6's), a Model Rocket News date April/May 1974,
and the Centuri Model Rocket Designers Manual (copyright 1971).

>[snipped]
> Thanks are plans for "Top Secret", a sort of neat-looking jet-styled rocket,
> and "pencil rocket", a rather boring rocket with a nice paint scheme.

I just built a slightly upscaled (bt20 -> bt50) "Intruder", the Honorable
Mention Design of the Month from my MRN.  Like the "Top Secret", this is
a jet-styled rocket.  Flys pretty nice.

> And the ads!  Sigh:
>
> Exotic Designs:
>[snipped]
>    Interceptor (a whopping) $5.25
There must have been a price increase, mine lists it at $5.95!

>[snipped]
> On the plus side, orders over $5 would give you a choice of a free
> Birdie or Sprite, $10 an Apogee II or a nighthawk, and over $15 a
> Cobra or Farside.

Mine charges for the bonus kits!  A Little John or Beta is $.35 for orders
over $6, Arcas or Goblin $.50 for over $9, and an Avenger or Cherokee "D"
for $.75 for over $12.

The cover of my issue introduces the "New Maxi-Brutes", an "almost 3 feet
tall" V-2 and an "over 3 feet tall" Pershing 1-A.  Only $13.95 each.  I
remember thinking (back then) that they looked nice but that I would never 
be able to afford them!

Jeff
--
Jeffrey A. Pleimling | [email-masked]
In Time, all things come to pass;
The Neglected become Loved, The Loved become Hated,       -Arthur Samuel Hyun
And the heroes feel the cold grip of death around their throats...

Article: 19938 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: Tripoli  Membership
Date: 13 Oct 1995 16:14:28 GMT
Lines: 9
Message-ID: <[email-masked]>
References: <[email-masked]>

DavidlB145 ([email-masked]) wrote:
: I  renewed  my  membership  a  couple  of  months  ago  yet  have  heard 
: nothing  back.  Is  this  typical?

You should be getting close.  Mine took 2-3 months recently.
--
Lee Reep 
 [email-masked] 

Article: 19939 of rec.models.rockets
From: [email-masked]
Subject: Lifting Body Technology Homepage
Message-ID: <[email-masked]>
Date: 13 Oct 95 07:11:02 CST
Lines: 46

Although still under construction, please visit my homepage dedicated to
"Lifting Body Technology".  I have put it together because I was having 
problems finding any data out there to help me with my lifting body model
rockets.  NASA does a wonderful job of informing the public but references 
are spread out on the net at different locations and all I have done is be a
focus to what I think is the neatest potential space vehicle ever.

 Lifting Body Technology HomePage  http://www.phoenix.net/~rocket/rocket.html

Also, please visit my personal homepage for my model rocket development.
Again, still under construction but I have places some photos out there to
show and tell what I'm up to.  These are only the phase I development vehicles
but I still have to use up the film in my camera before I place the beginings
of the phase II vehicles out there.  I will also be placing some of the
basic stamp programs I have developed out there as I finish them.

 My Lifting Body Model Development http://www.phoenix.net/~rocket/mac.html

Further, I have placed my club homepage out there.  It also has pointers to
all the neat sites I have found associated with model rocketry as well as
a mechanism of informing our menbers and others clubs of what we are up to.

 NASA/Houston Rocket Club HomePage http://www.phoenix.net/~rocket/club.html

I will try to update my pages every month so look out for a posting telling
you when I have or just visit for a while after the first of every month.
I think this is the best hobby ever and I just want to share it with you all.

                                 Cheers,
                                        Mac

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Mac 'Lifting Bodies' McGarrigle               | Work   :(713) 753-DUDE(3833)
 ([email-masked])                          | Fax    :(713) 753-5353
                                               | Club   :NASA/Houston
 "He who dies with the most friends wins"      | ICBM   :Not Telling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 NASA/Houston Rocket Club HomePage http://www.phoenix.net/~rocket/club.html
 Lifting Body Technology HomePage  http://www.phoenix.net/~rocket/rocket.html
 My Lifting Body Model Development http://www.phoenix.net/~rocket/mac.html
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Article: 19940 of rec.models.rockets
From: [email-masked] (William Walby)
Subject: Re: PISTON LAUNCHERS
Date: 12 Oct 1995 13:52:21 GMT
Lines: 20
Message-ID: <[email-masked]>
References: <[email-masked]>

BOBROWSKI ([email-masked]) wrote:
: Pardon this digression to what may not be HPR turf.

RMR is for ALL rocketry. So your questions are quite appropriate.

: Besides a description of design and operation I would enjoy whatever
: anyone can share in the way of their experiences, observations and
: opinions of piston launchers; and, just so this question is not a total
: waste of bandwidth, "Why not use upscaled pistons to launch HPR ?"  (Is
: there something I'm missing, like, 'Real rocketeers don't do pistons'?)

It is my understanding that using a piston launcher with composite motors 
does not work very well due to overpressurizaton produced by the piston.
But I have seen Aerotech D21's successfully launched from a piston by 
Warren Massey of LUNAR.

Get a piston from QCR and use that for your guide. 

Good Luck-
William

Article: 19941 of rec.models.rockets
From: [email-masked] (William Walby)
Subject: Re: Nichrome wire and reliable second stage ignition Q's
Date: 12 Oct 1995 13:59:20 GMT
Lines: 24
Message-ID: <[email-masked]>
References: <[email-masked]>

Tom Savard ([email-masked]) wrote:
: A week ago, I read a post about wrapping Nichrome wire around the Copperhead
: pyrogen to get a more reliable igniter. Where can I get some nichrome wire?
: I've found it being sold from a high purity alloy company, but the price
: seemed high:  $66 for 10 m of .5 mm diam.
SNIP

: I'm searching for a more reliable igniter because I'd like to start a second
: stage AP engine in the D-G range without the use of Thermalite. Does an
: electric match work for these smaller engines? Does the match require a
: supplemental pyrogen like the Copperhead tip or Thermalite? Are matches
: difficult to obtain (ie regulated)?

: Thanks-
: Tom Savard

Tom- Firefox Enterprises sells nichrome wire at reasonable prices. For 
non-thermalite ignitors get some of Firefox's Squibb pyrogen and make 
your own using pyrogen and nichrome. Warren Massey archived a document on 
this subject on Sunsite several months ago. I think it is entitled 
"Ignitor Talk". It is an excellent treatise on the subject.

Hope this helps
William

Article: 19942 of rec.models.rockets
From: [email-masked] (Paul Campbell)
Subject: Re: Nichrome wire and reliable second stage ignition Q's
Date: 13 Oct 1995 17:10:25 GMT
Lines: 15
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>
[email-masked] (Tom Savard) writes:

> If I new some of the popular uses for nichrome, I might be able to find it
> locally. Any suggestions?

Toasters - as a kid we used to use the elements of old toasters,
these are designed for higher current applications, you might
want to try and thin out one of those flat wires in toaster elements

---------------------------------------------------------------------
Paul Campbell - Taniwha Systems Design - Oakland CA USA
$cientology - the 'religion' for the '50s, where brainwashing is
a sacrament - if you think your newsgroup has wackos check out
alt.religion.scientology! (SP2 and bar)

Article: 19944 of rec.models.rockets
From: [email-masked] (Brian Day)
Subject: Re: Nichrome wire and reliable second stage ignition Q's
Date: 13 Oct 1995 14:41:04 -0500
Lines: 18
Message-ID: <[email-masked]>
References: <[email-masked]>

[email-masked] (Tom Savard) writes:

>A week ago, I read a post about wrapping Nichrome wire around the Copperhead
>pyrogen to get a more reliable igniter. Where can I get some nichrome wire?
>I've found it being sold from a high purity alloy company, but the price
>seemed high:  $66 for 10 m of .5 mm diam.

I've been saving the pieces of nichrome from the little bit of
Thermalite that I've got.  Each Thermalite ignitor that I use
results in (5?) extra pieces of nichrome wire.

I've been meaning to order some of the liquid "dipping" pyrogen
from Firefox to make some of my own ignitors.

bd
-- 
Brian Day                      [email-masked]
opinions blah blah disclaimers blah blah blah.

Article: 19945 of rec.models.rockets
From: [email-masked]
Subject: Re: Super Vega Body Tube...
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:07:38 CST
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Lines: 31

In article <[email-masked]>, [email-masked] (The Silent Observer) writes:
> This would be especially true if you can find some of the last 
> generation of metal film cans before the general conversion to plastic 
> -- they were aluminum, which is about as non-sparking as brass.

Boy, I haven't seen these for YEARS! You don't want to know what I used to
do with these.

> On the "bad news" side of this, a couple brands of film now come in 
> one-use, peel-top >fiber< cans (same stuff as old oil cans, or Comet 
> cleanser cans) that are just garbage after use.  Not reusable for 
> anything, AFAIK, not recyclable, and I'd question whether they save 
> resources relative to the plastic (though the wood pulp they're made 
> from is renewable).
> 
> The one brand I remember being packaged this way is Fuji -- but I've 
> made myself a mental note to avoid any brand I find with this packaging, 
> just on principle.

I haven't seen the paper only packs yet. I always liked Fuji because the
cans were clear, and I could see what I had in them. They are also moisture
proof, which is good for those who refrigerate their film...

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19946 of rec.models.rockets
From: [email-masked]
Subject: Re: Cone Heads (conical rockets)
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:37:33 CST
References: <[email-masked]>
Lines: 25

In article <[email-masked]>, [email-masked] (William Nichols) writes:
> I recall many years back that Centuri had a kit that was simply a cone
> w/o fins, and I know that Quest has a couple of kits that rely on body
> shape for stability.
> 
> I'd like to explore the subject of conical model rockets. What unique
> stability issues exist, if any? How does one calculate the CP? Is it a
> good or bad idea to have an air inlet up front near the pointy end of
> the cone? And, how stiff does the body need to be to avoid collapsing
> during flight?

The CP of a cone is easy to compute with Barrowman: it's 2/3 back from the
tip. To stabilise it, put the motor up forward in the cone. Be careful to
avoid the evil Krushnik effect. The old Centuri Point did this by putting
vents at the tip of the cone. If properly vented, stiffness is not much of
an issue. My Happy Meal food containers are basicly cone rockets.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19947 of rec.models.rockets
From: [email-masked]
Subject: Re: Could someone help with my Phoenix c.p. question ???
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:09:13 CST
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Lines: 16

In article <[email-masked]>, [email-masked] (Lee Reep) writes:
> I've used Slow Cure and not noticed any (detectable anyway) heating of
> the plastic, but you can set epoxy filled nose cone in the appropriate
> diameter jar of water to keep the plastic cool while the epoxy is curing.

Do this and it may not cure. Epoxy depends on heat to cure, usually
self-created. If you keep it cool, it may remain gooey for a long time...

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19948 of rec.models.rockets
From: [email-masked]
Subject: Re: Iron-on covering
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:30:24 CST
References: <[email-masked]> <[email-masked]> <[email-masked]>
Lines: 18

In article <[email-masked]>, Larry Klug <[email-masked]> writes:
> According to the RC people, dope and tissue is old technology that 
> really doesn't add much strength compared to a an iron-on covering.

Bull! You can't beat a good Tissue and dope finish for strength or weight.
For small models it's the ONLY way to go. An S8E sized RCRG is about the
smallest model you should even consider using iron-on coverings. If you want
the truth about tissue & dope, talk to free flight modellers. Their models
are more like our gliders than what the RC folks fly...

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19949 of rec.models.rockets
From: [email-masked]
Subject: Re: airfoiling fins
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:26:17 CST
References: <[email-masked]>
Lines: 35

In article <[email-masked]>, "John P. Petrakis" <[email-masked]> writes:
> What do most folks do when airfoiling 5-ply 1/8 inch plywood?
> I assume few people out there have the patience to put a full
> circular arc supersonic airfoil over the entire surface.  What is
> the most favored practice when it comes to this?  Leading and
> trailing edges sharp, rounded or what?

Contrary to comments so far, I don't recommend a Dremel tool for this. The
cutting area is so small compared to the edges of HPR fins, that it's too
easy to gouge them up. It also tends to be too agressive to too small of an
area for my taste.

I've had much better luck with a belt sander. I bought a Delta 4" belt/6"
disk sander many years ago. It's the only thing to use when airfoiling
plywood fins. You can sand the whole edge at once, making it much easier to
get a uniform airfoil. With a jig they turn nice circles for centering rings
too.

No, I don't use a "real" airfoil, but probably round back 1/2" from the LE,
and taper 1" up from the TE.

BTW, I strongly recommend abrasives (belts, disks, etc) from a place called
the Sanding Catalog. Their belts are all industrial quality, and last much
longer than anything else I've ever used. Their bargain boxes give you a
lifetime supply of useful sandpaper scraps. I can't find their 800 #, but
I'll post it here for those interested.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19950 of rec.models.rockets
From: [email-masked]
Subject: Re: launch report for central Illinois, 9/9
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:04:51 CST
References: <[email-masked]> <[email-masked]>  <[email-masked]>
Lines: 24

In article <[email-masked]>, [email-masked] (Jonathan Sivier ) writes:
>    5 minute epoxy has it's uses, but DON'T use it to glue together your motor
> mount, especially in high power rockets.  We had a incident here at one of
> our launches a few years ago which really illustrated the dangers.  Luckily
> no harm was done, but a valuable lesson was learned.  One of our members
> launched a high power rocket with a reloadable motor in which he had glued the
> motor mount together with 5 minute epoxy.  The heat from the motor was such 
> that the glue was melted.  Luckily the rocket recovered Ok, but when he pulled
> out the motor the whole motor mount came out as well.  The glue had become
> liquid with the heat.  While an Estes motor might not produce enough heat to
> make the glue run, it certainly will reduce it's strength.

Actually, an A3-4T casing can get as hot as most composites, and since they
are often used in minimum diameter models, the heat on the fin joints is
worse than most HPR models.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19951 of rec.models.rockets
From: [email-masked]
Subject: Re: Anyone with Estes nose cone information?
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:34:17 CST
References: <[email-masked]>
Lines: 29

In article <[email-masked]>, [email-masked] (Jeffrey A. Pleimling) writes:
> I've been trying to re-create some of my favorite, old Estes
> designs but have run into a problem - I don't know what their
> nose cone item number mean.  I know that a BNC-20N fits a BT-20,
> but what shape and length?

The letters don't mean anything in particular, except to distinguish one
shape from another.

> I know that BMC has replicas of *some* Estes nose cones, but
> they don't have every one.  With the right information, they
> can make them, however.

At NARAM-37, I talked with Bill of BMS. The patterns he is using came from
random cones bought in stores. Some of them are VERY POOR examples of what
they should be (the little BNC-5 "mosquito" cone for example). I've promised
to get him line drawings of all the old cones back to my 1963 catalog so
that he can reproduce them accurately. Actually, the BMS copies of the Estes
cones aren't very accurate IMHO: The Estes cones never fit very well, the 
BMS cones all fit correctly :-)

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19952 of rec.models.rockets
From: [email-masked]
Subject: Re: Confirmed at 14 years?
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:14:21 CST
References: <mgreenl.813338256@hubcap>
Lines: 21

In article <mgreenl.813338256@hubcap>, [email-masked] (Matthew S Greenlaw) writes:
> I got confirmed to fly class B motors at only 14 years old.
> I heard someone say you had to be 18--is this true? I have flown
> lots of class B motors, even clusters of class B. Thanx.

It's true. It's a federal regulation for use of motors over 80 ns, and it
isn't likely to get changed any time soon. If you want to fly for the next 4
years, you need to get an adult to purchase the motors and to "officially"
fly the model for you.

TRA used to confirm folks under 18, but stopped a while back. The NAR forms
specifically always stated that you must be over 18. Perhaps someone goofed. 

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19953 of rec.models.rockets
From: [email-masked]
Subject: Re: Igniting flashbulbs?
Message-ID: <[email-masked]>
Date: 13 Oct 95 13:11:08 CST
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>
Lines: 24

In article <[email-masked]>, [email-masked] (The Silent Observer) writes:
> As owner of an SX-70, I can confirm this last -- the Flashbar (R) is 
> fired by current direct from the 6V Polapulse (R) battery in the film 
> pack -- current drawn in competition with the motors that flip the 
> reflex mirror and drive the shutter circuits and light metering system, 
> as well as (on newer models than mine) operating the sonar and focusing 
> system.  AFAIK, there's not even a buffering capacitor to allow drawing 
> more current than the battery can supply -- though this would be less 
> needful with the Polapulse (R) battery, since it's designed to supply 
> power in shortish, high-current pulses, and is replaced every tenth 
> shot.

These batteries are ideal for launching rockets too. Short high-current
pulses are exactly what we need. For a while Estes had a launcher that used
this battery, but it seems it never caught on.

	Bob Kaplow			INTERNET: [email-masked]
USPO:	HealthCare COMPARE Corp, 5ISD, 3200 Highland Av. Downers Grove, IL 60515
TPC:	(708) 241-7919 x5327		ICBM:	41°49'48" North 88°0'51" West

	Apollo 13? Hell, I haven't even seen 1 thru 12 yet!

Disclaimer: If this message is caught or killed, the secretary will disavow
any knowledge of my actions. These bits will self destruct in 5 seconds....

Article: 19954 of rec.models.rockets
From: [email-masked] (Thomas Vandemerkt )
Subject: Re: Quote about Goddard
Date: 13 Oct 1995 23:15:50 GMT
Lines: 17
Message-ID: <[email-masked]>
References: <[email-masked]>

In <[email-masked]> [email-masked] 
(Frank J. Burke) writes: 

>
>I just saw this and thought it would be interesting:
>
>>  "Professor Goddard does not know the relation between action and 
>>  reaction  and the need to have something better than a vacuum 
>>  against which to react.   He seems to lack the basic knowledge 
>>  ladled out daily in high schools."
>>       --1921 New York Times editorial about Robert Goddard's 
>>  revolutionary rocket  work.
>
>

That just shows you that the media didn't know any more back then than 
it does now

Article: 19955 of rec.models.rockets
From: yuval kashtan <[email-masked]>
Subject: mail ordering
Date: 13 Oct 1995 20:55:42 GMT
Lines: 6
Message-ID: <[email-masked]>

Hello!
i wanna mail order rocket engines,
does any one know where from can i make mail order?
10x ahead for any answer...
byebye

Article: 19956 of rec.models.rockets
From: [email-masked] (Frank J. Burke)
Subject: Quote about Goddard
Date: 13 Oct 1995 22:29:24 GMT
Lines: 9
Message-ID: <[email-masked]>

I just saw this and thought it would be interesting:

>  "Professor Goddard does not know the relation between action and 
>  reaction  and the need to have something better than a vacuum 
>  against which to react.   He seems to lack the basic knowledge 
>  ladled out daily in high schools."
>       --1921 New York Times editorial about Robert Goddard's 
>  revolutionary rocket  work.

Article: 19957 of rec.models.rockets
From: [email-masked] (Matthew S Greenlaw)
Subject: Re: 100k feet altitude attempt?
Date: 13 Oct 95 03:28:41 GMT
Lines: 38
Message-ID: <mgreenl.813554921@hubcap>
References: <[email-masked]>

[email-masked] (David Perry) writes:

>I wonder if this is really possible.  I have a 27 kilo (54 lb.), 3 stage 
>rocket, using Aerotech's (N9600 (1st)/ N3050 (2nd & 3rd stages)).  The 
>rocket has a drag of Cd=.37  .   I ran many simulations using various 

   First, let me start off by wishing you the best of luck!  I think the 
vehicle you describe is quite capable of reaching 100K (just running 
through it roughly) assuming EVERYTHING goes right.
   The problem I have seen with many altitude attempts (especially staged
rockets) is that they do not boost straight up.
   IMHO, in order to reach that altitude, the vehicle is going to have to
have some kind of guidance system to help it maintain perfectly verticle 
flight.  Some method of fin control (VERY small movements) would likely seem
to be effective method of accomplishing this.
   Another thing to consider is a perfectly aerodynamically designed vehicle.
All three of those motors have a rather high impulse.  Assuming you ignite
all the motors, one after the other, the burnout velocity of the third stage
will be getting quite close to hypersonic velocity.  Fin sweep angle, nose
cone design, etc will be very critical.
   You did not mention if the CD was for subsonic or supersonic speeds.
Just because a vehicle has a low subsonic CD, does not mean the supersonic
CD will be equally attractive.  Many times, a higher subsonic CD transition
to a lower supersonic CD due to the effects of pressurization and shock
wave formation.
   Keep us informed on your progress of the vehicle!  I will be anxious to 
hear how it goes.

f

-- 
Matthew Greenlaw        |  Is 40:31 - "They shall mount up with wings
[email-masked]     |              as eagles..."     
Mechanical Engineering  |---------------------------------------------
Clemson, S. Carolina    |  http://Hubcap.Clemson.Edu/~Mgreenl 

Article: 19958 of rec.models.rockets
From: [email-masked] (Tony Wayne)
Subject: RotoRoc Questions
Message-ID: <[email-masked]>
Date: Fri, 13 Oct 1995 23:01:46 GMT
Lines: 28

ROTO ROC HELP NEEDED...

IUm trying to make a 1/2A Rotoroc. I hope I'm
using the term correctly. I'm trying a simple
design that I got from Qualified Competition 
Rockets, QCR. It is the cheap rocket. The fins
are fixed. The tops are flat and the bottom
is curved -like a wing air foil. The fins are
angled down at about 20 degrees from horizontal.
The nose cone is glued in and three holes are
drilled in the top. The motor is retained during
the flight with an engine hook.
	Anyways the rocket is supposed to rotate 
like a helocopter on the way down. Using an A3-4T
The rocket flew about 50 feet. On the way down 
is rotated around ...maybe 3 times total. Is
this flight why nobody uses this fixed fin
design?

	Are there any good tips to making this
thing rotate better? I've worked hard the air
foil w/o results.
-tony

---
Tony Wayne     	                              Those that can, do,
[email-masked]                          -those that understand, teach.

Article: 19959 of rec.models.rockets
From: [email-masked] (Tony Wayne)
Subject: Misquito Helped needed (URGENT)
Message-ID: <[email-masked]>
Date: Fri, 13 Oct 1995 23:02:37 GMT
Lines: 15

Misquito Questions

I know it would be easier to buy one, but
that is not an option this week.

1 How long is the Estes' Misquito body tube?
2 How long are the fins?
3 How wide are the fins? (Width perpendicular 
  to the leading edge).
4 What angle are the fins from the horizontal?
-tony

---
Tony Wayne     	                              Those that can, do,
[email-masked]                          -those that understand, teach.

Article: 19960 of rec.models.rockets
From: [email-masked] (Richard Gaff)
Subject: Re: Quote about Goddard
Date: 14 Oct 1995 02:47:31 GMT
Lines: 23
Message-ID: <[email-masked]>
References: <[email-masked]>

In <[email-masked]> [email-masked]
(Frank J. Burke) writes: 
>
>I just saw this and thought it would be interesting:
>
>>  "Professor Goddard does not know the relation between action and 
>>  reaction  and the need to have something better than a vacuum 
>>  against which to react.   He seems to lack the basic knowledge 
>>  ladled out daily in high schools."
>>       --1921 New York Times editorial about Robert Goddard's 
>>  revolutionary rocket  work.
>

  It was written in response to an article about Goddard and his idea
of sending a rocket to the moon that had been published the day before.
Not too surprisingly many people considered it farfetched.  Goddard
later conducted an experiment to show that rockets could operate in
space. Some years ago I looked up the entire editorial that quote is
from, maybe I should reprint it.

Rick Gaff

Article: 19961 of rec.models.rockets
From: [email-masked] (Richard Gaff)
Subject: Re: Yet more cheap tricks: Tube peeling...
Date: 14 Oct 1995 02:53:22 GMT
Lines: 26
Message-ID: <[email-masked]>
References: <[email-masked]>

In <[email-masked]> [email-masked] (William )
writes: 
>
 SNIP...

>Near as I can tell from NARTS plans, competition modelers have been
peeling
>the outer layers from ESTES style tubing for some time, although it's
not
>clear whether that's been an advantage...
>
>BillW

  Tube peeling by competitors was very common many years ago. It
reduced the weight of the model by a fairly significant amount. It's
kind of a pain to do however and if not done carefully the tube can be
ruined. I think that and the availablity of CMR parts and later Apogee
parts have made the technique obsolete for competion. Your use of
peeling for cheap sport rocket tubes however is rather interesting.

Rick Gaff

Article: 19962 of rec.models.rockets
From: [email-masked] (Paul Fossey)
Subject: Recovery Wadding
Date: 14 Oct 1995 02:48:09 GMT
Lines: 44
Message-ID: <[email-masked]>

In an attempt to reduce the cost per launch, I have been using cellulose wall 
insulation in place of the somewhat expensive Estes recovery wadding. This 
seems to work as well as or better than the commercial wadding.

I purchased the following at a Home Depot in Nashua NH.

Brand Name: Nature Guard Insulation.
Made from 100% Recycled paper.
Meets CPSC standard for flame resistance.
Cost: $3.00 for 25 Cu. Ft.
(Enough for many years of flying.)
--------------------------------------------------------------------
This helps, but there has to be a better way.....
--------------------------------------------------------------------
I have read some snippets in r.m.r about "gas cooling baffles", but there has 
not been any detailed descriptions.

The burn damage from the recovery deployment charge seems to be from burning 
embers rather than from exposure to a high source of heat spread over a wide 
area. If this is true, then the purpose of recovery wadding is to prevent 
these embers from reaching the recovery device.

Do you folks think the following would work?:

(Side view of motor mount)

Body Tube --->|              | 
              |=====    =====|<-- Baffle 1
              |              |     (Centered Hole)
              |=  ========  =|<---Baffle 2
              |              |     (Holes Around Outer Edge)
              |=====    =====|<---Baffle 3
              |              |     (Centered Hole)
              |  ||      ||  |
              |  ||      ||<-|----Engine
              |  ||      ||  |
              |  ||      ||  |

What could the baffles be made of so that they would not burn up over time? In 
this configuration, they would be difficult to repair or replace.
 
(Pardon my ASCII art....)

Article: 19963 of rec.models.rockets
From: [email-masked] (Buzz McDermott)
Subject: Re: Long, boring historical essay
Message-ID: <[email-masked]>
References: <[email-masked]>
Date: Sat, 14 Oct 1995 05:46:37 GMT
Lines: 40

A very interesting posting. Thanks for posting it. It so happens I've
been looking over a borrowed set of 1971-1972 'Model Rocketry' magazines
this week and G. Hary Stine had articles on the early history of Model
Missiles and model rocket motors in two of them.

  July 1971...The Old Rocketeer: Engines Full Circle

In this article Mr. Stine reports that Vern Estes came to MMI saying that he
could mass produce rocket motors for them. At the time, the Zenith Fireworks
Company had made the first big batch of motors for MMI, out of the casings 
for the 'Buzz Bomb' helicopter fireworks. It was made with an 18x70mm casing,
and that's where the 'standard' motor size came from. Vern Estes 'invented'
the first Mabel out of 'an old lathe that didn't have a starting capacitor
on the motor, with an old drill press, and with a tremendous amount of
ingenuity...'. Estes ended making far more motors than MMI could absorb and
sell, so Estes started up a mail order business to sell the surplus. Thus
the beginning of Estes Industries.

  December 1971...The Old Rocketeer: Letter to a Young Rocketeer

A history of MMI in this article. Mr. Stine says the MMI Arobee Hi with a
Rock A Chute 'Type A' motor weighed about 1.6 oz. He also mentioned that
the NAR started in 1959.  MMI sold one body tube and one nose cone, and only 
with the kits, not as separate items. All other rockets were made from 
paper tubes found around the house or hand-rolled tubes.

Again, thanks for the nostalgic look back. I got started in rocketry
in 1966 and was a NAR member the first time around starting in '69. I dropped
out of the hobby from sometime in the early 70's until about 1991. I agree
that the late 60's were a very unique set of years for the hobby. I agree
that a basic model rocket is muched unchanged from what MMI offered in 1957
or Estes offered in 1965. But we've learned a lot, made a number of significant
advances, and certainly upped the power range since then.

Buzz McDermott
YABAR
NAR 13559      (no where near as 'old fart' a number as 928, though! :-)

Article: 19964 of rec.models.rockets
From: [email-masked] (Steve Glines)
Subject: Re: First Wac Corporal Flight 50 Years Ago 10/11/45
Message-ID: <[email-masked]>
References: <[email-masked]>
Date: Sat, 14 Oct 1995 00:52:17 GMT
Lines: 19

	Just a quick follow up to this excellent history. Frank Malina
left JPL in 1951 (I think) and moved to Paris with the intent of founding
an intelectual salon. He suceeded and published a small magazine
called Leonardo (Pergamon Press). Franks son Roger Malina came to MIT in
1971. In 1973 he joined a Cambridge salon (well he hung around anyway) 
consisting of (among others) Jay Apt and Gorden Mandel. Roger moved to
Berkeley, became a professor and married Rupert Murdock's daughter, thus
saving Leonardo from the axe. Leonardo is (or was - I haven't seen a
copy in years) edited by the remnants of our commune in Cambridge.

ain't trivia grand.

PAX
Steve Glines
-- 

Steve Glines
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
<A HREF="ftp://ftp.netcom.com/pub/sg/sglines/homep.html">
My Home Page</A>
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Article: 19965 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: Re: 100k feet altitude attempt?
Date: 14 Oct 1995 05:35:20 GMT
Lines: 9
Message-ID: <[email-masked]>
References: <[email-masked]>

Howdy David,

I would love to fly one of my payloads on a vehicle of 
this caliber.  If you would like telemetry, I would love
to help in any way possible :)

-- 
John Dunbar

Article: 19966 of rec.models.rockets
From: John Dunbar <[email-masked]>
Subject: Re: mail ordering
Date: 14 Oct 1995 05:44:05 GMT
Lines: 20
Message-ID: <[email-masked]>
References: <[email-masked]>

yuval kashtan <[email-masked]> wrote:
>Hello!
>i wanna mail order rocket engines,
>does any one know where from can i make mail order?
>10x ahead for any answer...
>byebye
>

Glad you asked,  I would highly recommend Common Wealth Displays
located in Michigan.  They give great discounts for bulk and 
club orders.  If memory serves me, thier phone number is:
but I better not give it, because I'm not sure of it.  I'm sure 
its in the rmr faq, or someone reading this will email it to you.
If you get no reply, let me know and I will bring in the address 
from home for ya.  Ok, good luck!

-- 
John Dunbar

Article: 19967 of rec.models.rockets
From: [email-masked] (Wolfram v.Kiparsky)
Subject: Re: Recovery Wadding
Date: Sat, 14 Oct 1995 02:53:52 -0500
Lines: 27
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, [email-masked] (Paul Fossey) wrote:

> 
> Do you folks think the following would work?:
> 
> (Side view of motor mount)
> 
> Body Tube --->|              | 
>               |=====    =====|<-- Baffle 1
>               |              |     (Centered Hole)
>               |=  ========  =|<---Baffle 2
>               |              |     (Holes Around Outer Edge)
>               |=====    =====|<---Baffle 3
>               |              |     (Centered Hole)
>               |  ||      ||  |
>               |  ||      ||<-|----Engine
>               |  ||      ||  |
>               |  ||      ||  |
> 

This baffle ejection system is similar to one used in certain Centuri
kits, like the Nike Smoke.  The Centuri baffle ejection had just two
baffles, one with a series of holes around a small radius, and another
with a series of holes around a larger radius.  I recall that the baffles
worked well, and we never had our chutes melt.

Wolf

Article: 19968 of rec.models.rockets
From: nEtwAtchEr <[email-masked]>
Subject: Estes Sweet Vee Rocket Glider
Date: 14 Oct 1995 04:41:04 GMT
Lines: 6
Message-ID: <[email-masked]>

I have recently purchased the Estes Sweet Vee Glider.  I am considering
strapping on a motor instead of using a "D" engine.  Has anyone else?
Any tips?  Do you know of any good, related homepages?  Are there any
other newsgroups at which I should look.

Thanks.  Email me at [email-masked] for any answers.

Article: 19969 of rec.models.rockets
From: [email-masked] (AKhome)
Subject: Re: alt prediction?
Date: 14 Oct 1995 04:14:48 -0400
Lines: 5
Message-ID: <[email-masked]>
References: <[email-masked]>

     To find altitude all you need to do is some trigonometry.  mark off a
specific distance from the pad, (the bigger the better.)  Use an angle
measurer of some sort to find the angle of the rocket relative to you at
apogee.  Then take the distance from the launch pad and multiply it by the
tangent of the angle.

Article: 19970 of rec.models.rockets
From: GEORGE GASSAWAY <[email-masked]>
Subject: Re: US Spacemodeling Team
Date: Sat, 14 Oct 95 02:09:00 -0600
Lines: 60
Message-ID: <[email-masked]>
References: <[email-masked]>

Kevin McKiou mentieond he didn't know what happened to me in the flyoff round
in S8E. I came within a few second of the THIRD round ending by the time my
model finally got ignited - it had four misfires (I like the new E4.5 but
it's chamber pressure at ignition is such that it's hard to ignite, gotta
work on a better ignitor). One more misfire and I'd have been out of it. But
thanks to Jay Marsh & Ed LaCroix the final ignitor prepped worked, and there
happened to be tremendous lift by that time so maxing was easy. I had no idea
only three people had maxed all three rounds - I was very surprised when
after landing Jerry Gregorek came over to ask me about "the three of you"
doing the flyoffs in about 30 minutes, meaning I'd made the team, which was a
huge surprise.

As for my flyoff flight, the boost got off screwy, literally , as the bird
did a yawing slow roll that I was uneasy in trying to correct so I let it go
that way, hurt altitude a bit. But things otherwise were OK. I'd not had
trouble keeping the model penetrating into the wind all day, but in the
flyoff round it started to lose ground - drifting backwards while pointed
into the wind. Possibly I didn't have the same amount to trim set into it. I
was tempted ot give more downtrim to make it go upwind, but thought I'd lose
too much altitude, so let it go a bit. It kept getting worse, and in the end
got too far away downwind, where I lost orientation of it in left/right, it
was a silhouette in that very late near-sundown lighting conditions.  Could
not get it in control pointed into the wind, and it went down close to a
treeline in those VERY thick deep weeds. Nobody could find it. 
  Bad enough losing the model and gear was that it was a "virgin" model until
that day, 2 test boosts and 4 contests flights and that was it (Had planned
to do a good bit of practicing with it on Friday, but when the CHICAGO guys
won't practice fly you KNOW it's too windy....<g>). With the weather
conditions so unusual, I never really got a feel for whether that new design
flew like I wanted or not. At 250 sq inches and 186 gram glide mass, it was
meant to exploit light air, the kind of model I think would have been good
for the early morning final flyoff round in Poland last year. So, I'll have
to build another like that one and do some testing to see if I really like
that or want to vary the approach in yet another design iteration.

As for Scale & Scale Altitude,  as you said there is need for more people to
become active in that. There is a new prospect for Scale the next time, Jay
Marsh is "mentoring" Tom Campbell to prepare to try out for the 1998 scale
team, bulkding a Saturn-IB the same scale as Jay's.

Regarding the provisional "Rocketplane"/"Starship" event, that's a wierd one.
As I mentioned to Ben R., one model I've thought of making the last couple of
years is a "Original shuttle", based on the early concepts of winged booster
and piggyback orbiter.  Both would be R/C, of course. But then could FAI
judges accept the concept of one "entry" needing two pilots? Ah well, it's
not like I have a lot of time to try to make such a thing amid all the other
stuff to do in the next 10.5 months.

If some team member might like to try that event but not devote a lot of time
in building and so forth, maybe get hold of the Hobbylabs SR-71 kit? And for
those who might like to talk to an "idea man", they should contact Tom
Blakeney	(CIS#74242,272). He worked at Hobbylabs (SR-71), and has a personal
interest in building jet-like R/C and F/F rocket boosted gliders. 

- George Gassaway

 -> Alice4Mac 2.4.2 E QWK Eval:02Aug95

Article: 19971 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Igniting flashbulbs?
Date: 14 Oct 1995 08:09:44 GMT
Lines: 47
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, [email-masked] 
([email-masked]) says...
>
>In article <[email-masked]>, [email-masked] 
(The Silent
> Observer) writes:
>> As owner of an SX-70, I can confirm this last -- the Flashbar (R) is 
>> fired by current direct from the 6V Polapulse (R) battery in the film 
>> pack -- current drawn in competition with the motors that flip the 
>> reflex mirror and drive the shutter circuits and light metering 
system, 
>> as well as (on newer models than mine) operating the sonar and 
focusing 
>> system.  AFAIK, there's not even a buffering capacitor to allow 
drawing 
>> more current than the battery can supply -- though this would be less 
>> needful with the Polapulse (R) battery, since it's designed to supply 
>> power in shortish, high-current pulses, and is replaced every tenth 
>> shot.
>
>These batteries are ideal for launching rockets too. Short high-current
>pulses are exactly what we need. For a while Estes had a launcher that 
used
>this battery, but it seems it never caught on.
>

Unforunately, AFAIK, the Polapulse batteries are no longer sold separate 
from the film packs -- there were only ever a couple devices that used 
them (a traffic flasher, one sonar measuring unit based on the sonar off 
the SX-70 sonar-focus cameras, and the Estes launcher are all I know 
of).  One problem is that the battery is only designed to last ten flash 
shots, plus a reasonable amount of "camera unfolded" overhead -- the 
sonar cameras, especially the model with built-in strobe, would 
occasionally have a battery poop out on shot 8 or 9 (of 10).  That's 
about like launching a couple dozen models...and the batteries were 
>not< cheap.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19972 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Iron-on covering
Date: 14 Oct 1995 08:02:16 GMT
Lines: 34
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]> <[email-masked]>

In article <[email-masked]>, [email-masked] 
([email-masked]) says...
>
>In article <[email-masked]>, Larry Klug 
<larry_klug@studi
>o.disney.com> writes:
>> According to the RC people, dope and tissue is old technology that 
>> really doesn't add much strength compared to a an iron-on covering.
>
>Bull! You can't beat a good Tissue and dope finish for strength or 
weight.
>For small models it's the ONLY way to go. An S8E sized RCRG is about 
the
>smallest model you should even consider using iron-on coverings. If you 
want
>the truth about tissue & dope, talk to free flight modellers. Their 
models
>are more like our gliders than what the RC folks fly...
>

And let's not forget, if the model's a little too big for tissue, there 
are always Silkspan, and real silk -- both with real nitrate dope, of 
course!  B)

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19973 of rec.models.rockets
From: [email-masked] (The Silent Observer)
Subject: Re: Recovery Wadding
Date: 14 Oct 1995 08:16:25 GMT
Lines: 49
Message-ID: <[email-masked]>
References: <[email-masked]>

In article <[email-masked]>, Paul Fossey ([email-masked]) 
says...
>
>The burn damage from the recovery deployment charge seems to be from 
burning 
>embers rather than from exposure to a high source of heat spread over a 
wide 
>area. If this is true, then the purpose of recovery wadding is to 
prevent 
>these embers from reaching the recovery device.
>
>Do you folks think the following would work?:
>
>(Side view of motor mount)
>
>Body Tube --->|              | 
>              |=====    =====|<-- Baffle 1
>              |              |     (Centered Hole)
>              |=  ========  =|<---Baffle 2
>              |              |     (Holes Around Outer Edge)
>              |=====    =====|<---Baffle 3
>              |              |     (Centered Hole)
>              |  ||      ||  |
>              |  ||      ||<-|----Engine
>              |  ||      ||  |
>              |  ||      ||  |
>

Congrtulations!  You've reinvented baffle ejection!  B)

>What could the baffles be made of so that they would not burn up over 
time? In 
>this configuration, they would be difficult to repair or replace.
> 

Card stock, of similar weight to centering rings, or (for larger 
rockets) light plywood -- again, same weight as the centering rings in 
the model is a good starting point.

-- 
+----------------------------------------------------------------------+
| [email-masked] | Mass advertising on the Internet may become  |
| Owner/Operator of     | necessary, eventually ...                    |
| TableTop Publications |             ...but it will still be an evil! |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of the reader.                                             |
+----------------------------------------------------------------------+

Article: 19974 of rec.models.rockets
From: [email-masked] (PaulDiming)
Subject: Re: Launch Report Questions
Date: 14 Oct 1995 05:33:46 -0400
Lines: 13
Message-ID: <[email-masked]>
References: <[email-masked]>

Lee wrote:

>>I think you will find this group a fun one to read, and I believe all
of us have learned lots from the group.  There is tons of talent to
be found and captured here.<<

I'd like to second that!  When folks use meaningful subjects and keep the
content consistent within a thread, you can quickly scan 75-100 new
postings, picking up just want you need from the subject alone to know
whether to traverse the thread.  This group is worth definitely reading!

Paul.
Fly Baby Fly!

Article: 19975 of rec.models.rockets
From: [email-masked] (GordonMcD)
Subject: Re: Teaching kids...
Date: 14 Oct 1995 07:03:35 -0400
Lines: 6
Message-ID: <[email-masked]>
References: <[email-masked]>

Have you considered (gasp) soda pop bottle Water rockets?  Send them home
with a rocket of their own (and if you feel generous, the makings of a
launcher of their own, or at least one their class can keep.)
Gordon McDonough  InterPlanetary Water Rocket Society
Gordon McDonough
InterPlanetary Water Rocket Society

Article: 19976 of rec.models.rockets
From: [email-masked] (GordonMcD)
Subject: Re: Water Bottle Rocket
Date: 14 Oct 1995 07:50:56 -0400
Lines: 9
Message-ID: <[email-masked]>
References: <[email-masked]>

4' of parachute for 2 liter bottle sounds really big.  If you use the body
of an identical bottle for your nosecone, take a lap or two around your
motor bottle at the edge of its curve to keep the nose from jamming on and
to provide a stable shoulder.
You will find the bottle tumbles, and the trick is delaying the 'chute
deployment, I wrap them tight in their shrouds.

Gordon McDonough
InterPlanetary Water Rocket Society

Article: 19977 of rec.models.rockets
From: [email-masked]
Subject: New publication for rocketeers
Date: Sat, 14 Oct 95 10:10:09 EST
Lines: 19
Message-ID: <[email-masked]>

Danny Sagstetter, a model rocketeer for more than 40 years, is publishing "The 
Rocketeer Collector's Journal.  The RCJ contains articles on all aspects, 
current and historical, of collecting model & high power rockeets and products 
as well as for sale & trade sections.

I have known Danny for many years and have shared his interests.

If there is any interest, His address is:

Danny E. Sagstetter
4432 North Fourth Street.
Columbus, Ohio 43224-1035
Voice: (614) 268-6927
Fax: (614) 268-3247

He does not have an E-Mail address but if you would like, send requestes for 
info to [email-masked] and I will forward them to him.

Article: 19978 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: RMR Political? (was Re: Launch Report Questions)
Date: 14 Oct 1995 16:34:58 GMT
Lines: 20
Message-ID: <[email-masked]>
References: <199510101704.MAA00800@cybl35>

Mark Bundick ([email-masked]) wrote:

: Hey!  Have I been THAT heavy handed?  I mean, seriously, when was the
: last time there was a POLITICAL dogfight here???  And I read the launch
: reports, too!

: (whimper, whipmer......)

: ======================================================================
: Mark B. Bundick                "Running a NARAM will never be harder 
: NAR President                   than licking your political wounds. "

You've been awfully even-tempered, understanding, informative, ...

And call yourself a POLITICIAN?  :)

Lee Reep 
 [email-masked] 

Article: 19979 of rec.models.rockets
From: [email-masked] (Lee Reep)
Subject: Re: 5 minute epoxy
Date: 14 Oct 1995 16:38:50 GMT
Lines: 13
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

Mark Johnson ([email-masked]) wrote:

[...]

: And yes, Dave, I *do* wear rubber gloves. I keep a box of examining gloves on 
: my workbench. ...

Gosh, remind me never to visit your workshop.   :)

--
Lee Reep 
 [email-masked] 

Article: 19980 of rec.models.rockets
From: [email-masked] (Paul Gray )
Subject: New Web Site
Date: 14 Oct 1995 17:53:31 GMT
Lines: 10
Message-ID: <[email-masked]>

If any of you are new to this usenet newsgroup, or new to model
rocketry, check out my home page at this address:

http://www.wwebcom.com/pmgray/

The page covers up the basics of flying your first rocket. Hope this
helps!

Paul

Article: 19981 of rec.models.rockets
From: [email-masked] (LarryC)
Subject: Re: Plugging booster motors
Date: 14 Oct 1995 14:46:12 -0400
Lines: 26
Message-ID: <[email-masked]>
References: <[email-masked]> <[email-masked]> <[email-masked]>

I have a related problem. I want to do a series of high flights to measure Cd,
and a series of low flights to measure impulse for the same motor lot. The low
flights would be arranged by adding weight to the same air frames. Problem is
that a long delay is required for the high flights and a short delay for the
low flights. 

A possible solution is to buy short delay motors and modify them. The ejection 
charge would be removed, and replaced by thermalite or green fuse, wrapped 
in epoxy/cloth or something of that nature. When the plug/fuse is dry, the 
ejection charge would be replaced atop the new inlay, and plugged with a wad of
crepe paper. In effect, the fuse would serve as an extra delay for the same
ejection charge. 

It's a small modification, and a useful one, for those of us who want motor
specs on a given batch of motors chosen for Cd work. 

-Larry Curcio

PS I recently flew to Baltimore to get special dispensation from the Pope, but
I was dragged away and beaten when I tried to get close to him. I came to in
an alley behind the Bromo Seltzer Clock Tower. I'm almost recovered from the 
head injuries now, except for some residual pychopathic lying ... :-)