Subject: Please enlighten me on tapers.

From: <[email-masked]>
Date: Sun, 11 Sep 1994 13:02:06 CDT

Can someone give me the lo' down on the various tapers available?

I have a Sheldon lathe which I think has a #3 Morse taper in the
tailstock spindle.  The problem is I'm not sure I trust the
greasy piece of paper that this was written on.  Is there some
way that I can verify this by miking the taper of the center?
(No the center is not marked with its taper.)

Also are Morse and Jacobs tapers mutually exclusive?  I have a
taper mounted drill chuck wich is stamped as MT-3 and JT-2.

Are there other important tapers I can expect to run into?

I didn't see any of this addressed in the FAQ.

By the way, this is consistently the most helpful, to-the-point,
and civil group I've yet found on the net.  I tip my hat to
you all.

Thanks in advance for any info.

Chris Wieczorek
[email-masked]
University of Illinois at Chicago - Engineering Physics

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From: [email-masked] (Tim Kirby)
Date: 12 Sep 94 10:15:06 CDT

[email-masked] wrote:
: Can someone give me the lo' down on the various tapers available?

Hmmm. We have discussed it before but not for a while...

I just picked up my handy copy of Machinerys Handbook and realized that they
(it?) only lists Morse, Browne & Sharpe, Jarno and American National Std.
tapers... I don't see the rather common "R8" listed so this isn't
particularly exhaustive. Perhaps someone else can come up with a better list.

: I have a Sheldon lathe which I think has a #3 Morse taper in the tailstock
: spindle.  The problem is I'm not sure I trust the greasy piece of paper that
: this was written on...

Tailstock tapers are usually Morse (meaning "i've never seen one that wasn't")
:)

Large drills with tapers on the end are almost always morse tapers, I think,
so a tailstock with a non-morse taper would be a pain.

MT3 has a taper per foot of 0.60235 (taper per inch of 0.05205)

: Also are Morse and Jacobs tapers mutually exclusive?  I have a
: taper mounted drill chuck wich is stamped as MT-3 and JT-2.

Usually you have a Jacobs taper in the chuck and a morse taper in the
tailstock; the bit that joins them is a shaft with two tapers, which is
presumably the thing marked as you mentioned...

: By the way, this is consistently the most helpful, to-the-point,
: and civil group I've yet found on the net.  I tip my hat to you all.

Hey guys, we have a fan!.... :)

Tim
--
Tim Kirby _________ Cray Research Inc., Eagan, MN, USA __________ [email-masked]
Software Division              System Support                +1-(612)-683-5390
__________________________ Consider it disclaimed ____________________________
If all else fails, Immortality may always be assured by spectacular error(JKG)

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From: [email-masked] (Ken Toews)
Date: Mon, 12 Sep 1994 17:52:31 GMT

>Can someone give me the lo' down on the various tapers available?

You really need a machineries handbook, there are more tapers than
I have time to type.
>(No the center is not marked with its taper.)

Gently place a drill in the taper if it stays its a morris
>taper mounted drill chuck wich is stamped as MT-3 and JT-2.

Morse taper is apx 5/8 of an inch per foot, Jarno tapers that
are on many lathes spindles are .600 on the diameter

JT-2 will be the taper on the inside of the drill chuck, you
can take the taper part of the chuck part. The two are held
together by a taper.
>Are there other important tapers I can expect to run into?

Brown and sharpe tapers on dividing heads, R-8 on small mill
spindles, it really goes on and on...
>and civil group I've yet found on the net.  I tip my hat to

For the reaal flame wars you have to check out crafts.metalwork.progressive
it can get really dirty.

--
Ken Toews    *            In life effects are certainty while causes
                          a however conspicuous are always harder to pin down.
***************************************************************************
.....Stay Hungry Stay Foolish...Otherwise you'll end up fat and boring.....

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From: [email-masked] (Peter Wiley - Poultry)
Date: 12 Sep 1994 06:13:03 GMT

There is every taper known to mankind then some listed in Machinerys Handbook.

Better alternative; clean out the tailstock ram and try a 2 and 3 MT drill
sleeve, drill arbor or other known size MT. Only 1 will fit. Most prob 2 or
3 unless it's a really big lathe.

As for the chuck arbor tapers, the JT goes into the hole on the back of the
chuck. The MT goes into the machine spindle. Therefore, 2 taper designations.
Simple after you play with this stuff for a while but confusing to start.

My advice is to buy a copy of Machinerys Handbook. Doesn't have to be new. This
has so much useful information for metalworking in it that you'll never even
agree to *lend* your copy...

Peter Wiley

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From: [email-masked] (J.R. Stoner)
Date: Mon, 12 Sep 1994 23:16:11 GMT

In article <[email-masked]>,
Tim Kirby <[email-masked]> wrote:
;[email-masked] wrote:
;: Can someone give me the lo' down on the various tapers available?

;Hmmm. We have discussed it before but not for a while...

;I just picked up my handy copy of Machinerys Handbook and realized that they
;(it?) only lists Morse, Browne & Sharpe, Jarno and American National Std.
;tapers... I don't see the rather common "R8" listed so this isn't
;particularly exhaustive. Perhaps someone else can come up with a better list.

;: I have a Sheldon lathe which I think has a #3 Morse taper in the tailstock
;: spindle.  The problem is I'm not sure I trust the greasy piece of paper that
;: this was written on...

;Tailstock tapers are usually Morse (meaning "i've never seen one that wasn't")

;Large drills with tapers on the end are almost always morse tapers, I think,
;so a tailstock with a non-morse taper would be a pain.

;MT3 has a taper per foot of 0.60235 (taper per inch of 0.05205)

;: Also are Morse and Jacobs tapers mutually exclusive?  I have a
;: taper mounted drill chuck wich is stamped as MT-3 and JT-2.

;Usually you have a Jacobs taper in the chuck and a morse taper in the
;tailstock; the bit that joins them is a shaft with two tapers, which is
;presumably the thing marked as you mentioned...

A little more rare, is a taper-mount end mill.  If one of these puppies are
found, it had better have a Weldon shank, and not a clean taper.

The purpose of the flattended shank, is to provide a place to land a setscrew
so that the cutter is truly rigid in the headstock (or mill quill).  You will
be truly amazed at the axial forces to be found by an endmill worming out of
a lathe chuck, no matter how tightly you crank it in.  At minimum you ought to
have some kind of drawbar setup (HSM this month has a pretty good plan for one)
to pull in the cutter into your headstock.  Otherwise go and buy a taper
arbor adapter, so that you get a rigid lock.
-- 
.J.R. Stoner, Ferroequinologist - [email-masked] - [email-masked]