crossslide screw/nut repair - was Re: Re: some notes


gorvil
 

You can "bootstrap" the repair. Lock the cross slide by tightening
the gibs and use the compound to feed the tool into the work. I've
done it. I made a small boring bar to accept a piece of 1/8" drill
rod for a cutting tool and ground the end of the drill rod to match
the shape of the thread on the screw. There is not much room inside
the nut for manuvering.

Glen Reeser


--- In southbendlathe@yahoogroups.com, Ed Beers <sreeb@b...> wrote:
I just finished up my screw rework and nut fabrication. The
crossslide
moves smoothly over the entire range and backlash is 0.006. I
could
probably improve the backlash with another nut or splitting the
nut but
I'm pretty happy with it as is so I'm going to just call it a
success.

Thanks to Ron for suggesting this method and point out a few
misconceptions I had.

A few comments on doing this:

1) My screw appeared to made from 12L14 and machined nicely. I
don't
know if they all are. My machine has a War Board sticker on it so
it is
older and may have been built in a hurry or with limited resources.

2) You need a functioning lathe to do this so you can't bootstrap
the
repair.

3) I found grinding the tool to thread the nut the hardest part.
The
hole is small and deep while the threads are also deep. Getting
the
necessary clearances while retaining rigidity was difficult.

4) I don't think it would be very hard to make a new lead screw so
that
would be my first option if I didn't have access to a second lathe.
This would also allow use of a tap to make the nut.

Ed

Join SouthBendLathe@groups.io to automatically receive all group messages.