Ignoramus25487 wrote:
On Mon, 23 May 2005 15:11:59 GMT, Lloyd E. Sponenburgh
wrote:

"Ignoramus25487" wrote in
message ...
I tried threading a 3/4" shaft with it recently.

My problem with it is that the lathe is very slow to stop. When I
turn
the lathe off, it takes a few revolutions for it to stop. There is
no
automatic way to stop, like on a lathe that I practiced on 18 years
ago. So my threading bit can end up anywhere.

What is the standard approach to this problem.

First, turn a "land" at the point where you wish the threads to
stop. Make
the diameter just at, or a couple-thou under the minor diameter of
the
thread.

IF you have a threading dial, and don't have to reverse your lathe
to get
back to the start of the threads --

When the tool enters the land, disengage the longitudinal feed
(halfnuts),
then stop the lathe with the tool still in the land.

Watching carefully, you can stop in a land barely more than one
thread pitch
wide.

If you don't have a threading dial, be right quick on the
cross-feed, and
back the tool out rapidly when it hits the land. Then stop the
lathe,
reverse, etc.,etc..

Thanks. What about simply reversing the lathe, would that not keep the
bit exactly where it needs to be on the thread?

i
NO!
Backlash will have it all over the place.
Ken.