Just a couple of pictures of an internal taper I made using the
compound slide on my SB Heavy 10 lathe. The workpiece in the photos
is the underside of a shop-made turret-type tool post for the same
lathe. For scale, this is a 4" square tool post that takes 1/2"
square tool bits, and the clamping screws are 7/16".

The reason for the taper was an experiment based on the idea
that the taper presents more surface area per unit of length,
and therefor better grip when the indexing lever is tightened.
I forget the included angle of the taper (I made this last year)
but it is obvious that it is a self-releasing type.

http://pages.cthome.net/fcf/tp-taper1.jpg

I post pictures of this because I'm particularly proud of the fine
finish I was able to achieve with just the (hand-fed) compound slide.

http://pages.cthome.net/fcf/tp-taper2.jpg

The mating post (what would that be called?) has a similar finish (no
pictures available).

Thanks for indulging me!

Artemia Salina wrote:
Just a couple of pictures of an internal taper I made using the
compound slide on my SB Heavy 10 lathe. The workpiece in the photos
is the underside of a shop-made turret-type tool post for the same
lathe. For scale, this is a 4" square tool post that takes 1/2"
square tool bits, and the clamping screws are 7/16".

The reason for the taper was an experiment based on the idea
that the taper presents more surface area per unit of length,
and therefor better grip when the indexing lever is tightened.
I forget the included angle of the taper (I made this last year)
but it is obvious that it is a self-releasing type.

http://pages.cthome.net/fcf/tp-taper1.jpg

I post pictures of this because I'm particularly proud of the fine
finish I was able to achieve with just the (hand-fed) compound slide.

http://pages.cthome.net/fcf/tp-taper2.jpg

The mating post (what would that be called?) has a similar finish (no
pictures available).

Thanks for indulging me!


Nicely done.

In article , Artemia Salina
says...

The reason for the taper was an experiment based on the idea
that the taper presents more surface area per unit of length,
and therefor better grip when the indexing lever is tightened.

Another way to do this is to put a circular pattern of centerdrill
holes in both parts. Then if you put steel balls in there, you
index according to the patterns. This is they way the Enco
toolposts work. They use an O-ring to keep chips and junk out of
the mechanism.

The obvious disadvantage is that they only index in fixed increments.

Your setup will be infinitely adjustable.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

Artemia Salina wrote:
... I post pictures of this because I'm particularly proud of the fine
finish I was able to achieve with just the (hand-fed) compound slide.
...

I was turning a Morse taper using the compound once and got so
frustrated with the inconsistent hand feed that I took a cordless drill
and chucked up the end of the compound feed screw. Reeaall nice.
Reverse, too. Bob

On Fri, 02 Sep 2005 22:47:32 -0400, Bob Engelhardt wrote:

Artemia Salina wrote:
... I post pictures of this because I'm particularly proud of the fine
finish I was able to achieve with just the (hand-fed) compound slide.
...

I was turning a Morse taper using the compound once and got so
frustrated with the inconsistent hand feed that I took a cordless drill
and chucked up the end of the compound feed screw. Reeaall nice.
Reverse, too. Bob

*Great* idea! I suppose you could make a bit for the drill that
would slip over the hand crank. Something shaped like a tuning fork
with short tines and wire insulation over them (to prevent marring
up the hand crank).

I'll have to play with that!