Subject: tapers and how to?

From: Bob Bickers <[email-masked]>
Date: 11 May 1996 21:08:33 GMT

I have a taper attachment on my lathe but have never used it, so have been trying it out. 
Problem how does one pick up an existing taper, ie the one in my head stock? I've mounted a 
test indicator on the cross slide, adjusted taper att. to aproximate taper, but indicator will 
always encrease in value then sometimes decrease or encrease depending on how att. is set, as 
the indicator enters headstock. Should I insert indicator all the way in headstock and observe 
readings exiting or should I be reading it going in? Does anyone know the taper used by Logan, 
it's not Morse, nor Jarno, maybe 4 degress? Thanks Bob

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From: Mark Marks <[email-masked]>
Date: 12 May 1996 22:17:39 GMT

> Does anyone
>know the taper used by Logan, 
---
The spindle on the Logan 800 series is a #3 Morse.
The manual for the Logan 800 states:  "The nose is 1.5" diameter 
with 8-pitch National Form threads and has been turned internally 
to a No. 3 Morse Taper."

Mark Marks, Florida

---

From: Bob Bickers <[email-masked]>
Date: 13 May 1996 03:23:30 GMT

I should have stated that I have a model 6560  14X40. Looking in the parts book Logan used 2 
and 3.75 degrees, mine is neither, futher testing today makes me 98% sure its 4degrees.

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From: [email-masked] (Scott Logan)
Date: 13 May 1996 12:04:44 GMT

>> Does anyone know the taper used by Logan, it's not Morse, nor Jarno,
maybe 4 degress? <<
        ^^^^^^^

Bob,

You should learn to ask the source...

The Logan 11, 12, & 14" Lathes used a proprietary taper of 3 degrees, 35
minutes from center until serial number 52576 (approx. late 1949). 
After that, it was 2 degrees from center.

--
>From  Scott Logan,
http://ourworld.compuserve.com/homepages/LoganAct
Reply to [email-masked]

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From: Steve Wellcome <[email-masked]>
Date: 13 May 1996 13:59:12 GMT

Are you be careful to have the indicator lever set at center height
while you're trying to measure the taper?

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From: Bob Bickers <[email-masked]>
Date: 14 May 1996 22:30:02 GMT

Yes Very! Bob

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From: Bob Bickers <[email-masked]>
Date: 14 May 1996 22:45:34 GMT

>After that, it was 2 degrees from center.
Thanks Scott, my lathe was built in '59, but 2 degrees doesn't work out. Unless, UNLESS the 
4degrees showing on the taper attachment means encluded angle. I'm using a test indicator on 
the cross slide and run it in the spindle using the taper att. adjusting it till I get no 
movement on the gauge [+ or - .0005"] in 2+" of travel. Then with this adjustment I place a 
mandrel between centers and read with a dial indicator the travel in 4" which should equal 
sine of angleX4 and I get an angle slightly less than 4degrees but not as small as 3degrees 
35min. Maybe my spindle has been modified?  Bob

From 71165.3406
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From: "Robert A. Wise" <"71165.3406 "@ compuserve.com>
Newsgroups: rec.crafts.metalworking
Subject: Ultrasonic drill
Date: Tue, 14 May 1996 17:42:21 -0700
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I recently bought an ultrasonic drill (lapidary), made by Imahashi mfg.
It was marketed as GemSonic Mini-Drill.  I found it in a catalog from the 
now defunct Geode Industries.  It sold for $706.00 in 1977 (with optional 
slurry pump).  I would truly love to find a copy of the manual for this 
tool. Barring this,  I would also like to talk to someone who would have 
perhaps used one, knows about available parts, tuning, etc.
Thanks,

Robert Wise

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From: [email-masked] (Jonathan M. Elson)
Date: 15 May 1996 04:54:21 GMT

Bob Bickers ([email-masked]) wrote:
: I have a taper attachment on my lathe but have never used it, so have been trying it out. 
: Problem how does one pick up an existing taper, ie the one in my head stock? I've mounted a 
: test indicator on the cross slide, adjusted taper att. to aproximate taper, but indicator will 
: always encrease in value then sometimes decrease or encrease depending on how att. is set, as 
: the indicator enters headstock. Should I insert indicator all the way in headstock and observe 
: readings exiting or should I be reading it going in? Does anyone know the taper used by Logan, 
: it's not Morse, nor Jarno, maybe 4 degress? Thanks Bob

The reason you get the varying readings inside the spindle taper is most 
likely wear inside the spindle.  This makes the taper really hard to pick up.
You might try visually inspecting the internal taper to see if you can
locate an area of minimum wear.  Pick up the taper from that area.
The usual way is to find out what taper you (are supposed to ) have, and then
set the taper attachment with gauge blocks, sine bars and calipers.  
Actually, if the taper attachment provides a reference surface for zero 
taper, then all you need is a sine block and a caliper (or the right gauge
blocks) to get the angle needed.  This will be a heck of a lot more accurate
than trying to pick up the taper from a worn spindle.

Machinery's handbook provides 3 methods for measuring and setting tapers.

---

From: Bob Bickers <[email-masked]>
Date: 19 May 1996 14:25:50 GMT

[email-masked] (Scott Logan) wrote:

>
>BTW, one nit to pick.  If my math isn't completely messed up (a distinct
>possibility) you would need to use the tangent, not sine.  Tan A=a/b.
>A=angle from centerline, a=indicator reading, b=travel length (along
>bed, not along taper slide).
>
>What readings are you getting?  From my figures, you should have 0.1397"
>indicator travel in 4" bed travel for 2 degrees from center.  If 3 deg.
>35 min., it should be 0.2505".
> 
>
>--
>From Scott Logan,
Right you are Proffessor Logan, its tangent I need, can't trust 35 year old trig lessens, read 
"the brain that contains them", now all the numbers come out right.:) And yup its 2 degrees. 
>From  all this I've learned 1 when picking up a taper, ensert the test indicator as far into 
the spindle as possible and engage surface then withdraw indicator along taper, not to push 
indicater. 2, that my taper attachment reads encluded angle.
Thanks Scott   Bob

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From: Bob Bickers <[email-masked]>
Date: 19 May 1996 14:26:49 GMT

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From: Bob Bickers <[email-masked]>
Date: 19 May 1996 14:27:44 GMT

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From: Bob Bickers <[email-masked]>
Date: 19 May 1996 14:28:01 GMT

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From: Bob Bickers <[email-masked]>
Date: 19 May 1996 14:38:48 GMT

>35 min., it should be 0.2505".
Ah, right you are Professor Logan, its tangent I need, never trust 35 year old trig lessons, 
read "the brains that contain them", and jup its 2 degrees. From all this I've concluded that 
the taper attachment reads the encluded angle, 4 degrees in this case and one should not push 
a test indicater but rather pull it along a surface to get an acurate reading. Thanks Scott, 
cheers. Bob

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From: Bob Bickers <[email-masked]>
Date: 19 May 1996 23:42:13 GMT

The [my] capacity to screwup alway amazes me. Bob

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From: [email-masked] (Russ Kepler)
Date: Mon, 20 May 1996 12:04:34 GMT

In article <[email-masked]>,
>The [my] capacity to screwup alway amazes me. Bob

Hang around a while - some of us have the capacity to astonish you
with our ability to screw up.

-- 
Russ Kepler posting from home  [email-masked]

                      Please don't feed the Engineers