Subject: Home Foundry, At Last!

From: [email-masked]
Date: 22 Jul 1996 14:44:53 GMT

Well, it finally has happened!  Thanks to all the people that responded to my questions, I am 
finallly casting aluminum.  I bought a #4 furnace setup from Pyramid (in the FAQ) . That took
care of the crucible,tongs,propane regulator etc.  A trip to a local foundry took care of aluminum
stock, I bought 100# of their gates and sprues at slightly less than the price for virgin ingots.
I knew that I wanted to use Petrobond sand for casting.  Bought some Petrobond II and found that
it was just the bonding agent; sand and "petrobond" oil was required.  Being impatient, I mixed up 
some green sand using playbox sand from the local hardware store and made some castings.  
They turned out great!  

Am now getting the right stuff for Petrobond.  Despite what I have seen in this newsgroup, very fine
silica sand is still available from the local sandblasting suppliers ( 120-400 grit).  The petrobond oil
was a major pain in the ....  They will only sell it in 5 gallon pails (2 pints will do 100# of sand).  After 
much checking, I found an equivalent oil available thru Grainger Supply, a Mobil product (circulating
oil, ISO grade 100) available in quart and gallon containers.  Hint, this oil is also recommended as an
air compressor oil.

I have just purchased a small sand muller to blend Petrobond.  Should be here this week.  If anyone in the
WI area wants some petrobond sand, I should be able to help you.

Many thanks to Winston Harness (brnzcaster) for his web page that led me to the muller!

John Lovallo

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From: [email-masked] (BrnzCaster)
Date: 22 Jul 1996 13:05:00 -0400

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

> The petrobond oil was a major pain in the .... 

Congratulations John on your first pours.
You can use 30W NON-detergent motor oil for the bond oil in PetroBond and
Aridry casting sands.
It's been a few years since I used any PetroBond, so I've lost track of
the Part No. If anyone is using Aridry (Borden) sand, specifiy J-82MX for
the pre-blended mix (just J-82 is the binder).
Winston
--
Winston W. Harness
http://ourworld.compuserve.com/homepages/brnzcaster/
--

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From: [email-masked](J.A.Harvey)
Date: 23 Jul 1996 00:33:06 GMT

In <[email-masked]> [email-masked] writes: 
>
>Well, it finally has happened!  Thanks to all the people that 
Congratulations John!

You will find that dealing with pyramid is a real pleasure. Merle ( the
owner) is a very knowledgable fellow and will help you rihgt along. His
furnace is a gem and really works beautifully!

And if Winston gives you any advice TAKE IT! That man is an
encyclopedia of casting knowledge.

Next time you talk to Merle, tell him I said hello!

Best of luck with your casting.

Jim Harvey
[email-masked]
http://hre.com/

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From: [email-masked] (Greg Lewis)
Date: 24 Jul 1996 12:27:56 -0700

In article <[email-masked]>,
>the pre-blended mix (just J-82 is the binder).

So if 30 non-detergent works, why can't you just get some fine sand
>from  the local sandblast supply and add the 30 wt. oil?

Is there something else in the PetroBond?

___________________________________________________________________
[email-masked]      	   	     They don't
Photojournalism sequence      	   	     Call this place
Department of Mass Communication   	     An institution
     and Journalism 	      	   	     For nothing
CSU Fresno, Fresno, CA 93740-0010

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From: [email-masked] (BrnzCaster)
Date: 25 Jul 1996 10:10:42 -0400

>Is there something else in the PetroBond?

Yes, there is some sort of resin, plastic, etc bonding agent. I've tried
for several years to determine what it is but haven't found the answer
yet.
I have seen several postings and book/article reference making an
oil-bonded casting sand without this mystery compound ... even Bill Ammen
has given various brews ... but none are viable for use as far as I can
determine.
I buy both the premixed casting sands and the straight binder for making
my own special facing sands. You can take the binder compound powder (red
or tan powder about the fineness of body talc) and hit a small pile with a
propane torch flame and it will burn, so it is some sort of organic
material.
Winston
--
Winston W. Harness
http://ourworld.compuserve.com/homepages/brnzcaster/
--

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From: [email-masked] (Kurt Rieder)
Date: 26 Jul 1996 16:03:31 GMT

J. Kimberlin ([email-masked]) wrote:
: In article <[email-masked]>,
: BrnzCaster <[email-masked]> wrote:
: >Yes, there is some sort of resin, plastic, etc bonding agent. I've tried
: >for several years to determine what it is but haven't found the answer
: >yet.
: >I have seen several postings and book/article reference making an
: >oil-bonded casting sand without this mystery compound ... even Bill Ammen
: The only thing I can think of that is red or tan powder would be powdered 
: rosin.  It is organic, burns, and is certainly a binder used for 
: castings.  I think we used it for shell mold manufacture at Link-Belt 
: when I was their foundry chemist in 1962.  Don't quote me, that was 34 
: years ago.  I could analyze it if I had some.

I think that perhaps what is being referred to is a phenolic resin.
If it has an odor which reminds you of old fashoned library paste... 
that's probably what it is.  Sort of an "uncured bakelite" in fine 
powder (golden, tan, light brown).  At oven temperatures the resin
will cure and bond the core, and at higher temperatures the resin
will be destroyed and the core crumbles.  One maker... in the past
at least... was Union Carbide.  If you use the term "phenolic resin",
foundry suppliers should know what your talking about.

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From: [email-masked] (J. Kimberlin)
Date: 25 Jul 1996 16:12:04 -0700

In article <[email-masked]>,
>propane torch flame and it will burn, so it is some sort of organic

The only thing I can think of that is red or tan powder would be powdered 
rosin.  It is organic, burns, and is certainly a binder used for 
castings.  I think we used it for shell mold manufacture at Link-Belt 
when I was their foundry chemist in 1962.  Don't quote me, that was 34 
years ago.  I could analyze it if I had some.

JerryK