On 2008-07-16, DoN. Nichols wrote:
_/ \_/ \_/ \_/ \_

But the middle looked like this:

_/\__/\__/\__/\ _

The nut was worn too -- but not nearly as much as the leadscrew.


I have this too, but not much. I received the nut today and it does
fit the leadscrew. I machined it today to be of yoke shape instead of
square. I need to solder a little extra brass padding to complete the
shape, and drill/tap that for the screw. I hope to have a replacement
in a few days. I will not in any way disturb the original nut, so this
is all quite safe.

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On 2008-07-15, Ignoramus22312 wrote:
On 2008-07-15, catguy wrote:

"Ignoramus22312" wrote in message
...
Now that I have my lathe "working", I started looking at its condition
a little more closely. On my lathe, the cross slide is moved by a
3/4-5 ACME screw, that moves a brass nut attached to the cross slide.

There is a lot of wear in this, as in, maybe 1/16 to 1/8" of slop.

snip stuff

Is this what you are refering to?....Paul

http://cgi.ebay.com/ws/eBayISAPI.dll...m=140238453069


Looks like a great find, but this is for a different Clausing.

It also is for a different part of the lathe. This is a
leadscrew and nut for the compound, not the cross-slide.

Enjoy,
DoN.

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DoN. Nichols wrote:
... The nut was worn too -- but not nearly as much as the leadscrew.

!!! That's not good - it would be much better to have to replace the
nut than the lead screw. Or do you suppose that the nut had already
been replaced, perhaps more than once?

If not, do you suppose that the nut being softer had picked up steel
dust & had acted as a lap on the screw?

Is this normal?

Bob

"Ignoramus19502" wrote in message
...
On 2008-07-15, Mike Henry wrote:

"Ignoramus22312" wrote in message
...
On 2008-07-14, Ned Simmons wrote:
On Mon, 14 Jul 2008 10:36:05 -0500, Ignoramus22312
wrote:


Has anyone dealt with this issue. Clausing wants $750 (not a typo) to
custom make this part for me.

4) Split the nut and make it adjustable. I've done this on two
machines, a lathe and a surface grinder.

It is in such a bad shape, that doing so would not help.

On the lathe, the nut was rectangular and there was enough material
around the thread to install two guide pins and two adjusting
screws. Drill and ream for the guides before cutting the nut in
two.

The grinder's nut was cylindrical with a thin wall. I cut it in half
and turned a fine male thread on each piece. A coupler with matching
threads and the same OD as the nut allows for lash adjustment.

None of these options will account for the inevitable unequal wear in
the lead screw.

The lead screw is just $22 at McMaster-Carr, I will just buy it if I
find a lot of wear on the existing one, but I expect (and saw) most of
the wear on the brass nut. So I will start with the nut first.


I'm not positive, but suspect that the nuts and leadscrews sold by
McMaster-Carr might be somewhat low precision. That might not be
important
for the compound or cross slide where travel is usually short, but you
should be aware of it so you can make an informed decision.


I think that all cross slides should have backlash, I just want to
have it smaller. I think that I can do it without breaking anything
and can always reuse the old nut.


I was thinking more in terms of the error per unit of screw length, such as
an error of 0.003"/inch of screw. That number is pulled out of thin air so
is probably not typical and may not even be close to typical. And again,
the issue is probably not a show stopper, just sonething you should be aware
of.

On 2008-07-16, Mike Henry wrote:

"Ignoramus19502" wrote in message
...
On 2008-07-15, Mike Henry wrote:

"Ignoramus22312" wrote in message
...
On 2008-07-14, Ned Simmons wrote:
On Mon, 14 Jul 2008 10:36:05 -0500, Ignoramus22312
wrote:


Has anyone dealt with this issue. Clausing wants $750 (not a typo) to
custom make this part for me.

4) Split the nut and make it adjustable. I've done this on two
machines, a lathe and a surface grinder.

It is in such a bad shape, that doing so would not help.

On the lathe, the nut was rectangular and there was enough material
around the thread to install two guide pins and two adjusting
screws. Drill and ream for the guides before cutting the nut in
two.

The grinder's nut was cylindrical with a thin wall. I cut it in half
and turned a fine male thread on each piece. A coupler with matching
threads and the same OD as the nut allows for lash adjustment.

None of these options will account for the inevitable unequal wear in
the lead screw.

The lead screw is just $22 at McMaster-Carr, I will just buy it if I
find a lot of wear on the existing one, but I expect (and saw) most of
the wear on the brass nut. So I will start with the nut first.


I'm not positive, but suspect that the nuts and leadscrews sold by
McMaster-Carr might be somewhat low precision. That might not be
important
for the compound or cross slide where travel is usually short, but you
should be aware of it so you can make an informed decision.


I think that all cross slides should have backlash, I just want to
have it smaller. I think that I can do it without breaking anything
and can always reuse the old nut.


I was thinking more in terms of the error per unit of screw length, such as
an error of 0.003"/inch of screw. That number is pulled out of thin air so
is probably not typical and may not even be close to typical. And again,
the issue is probably not a show stopper, just sonething you should be aware
of.


I think that I will simply buy a dial indicator with a long stem. Kind
of a poor man's digital readout.
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On 16 Jul 2008 04:24:23 GMT, "DoN. Nichols"
wrote:

And at least you have a larger bore than I did. Beware that you
will probably need to make a left-hand thread ACME, not just a normal
ACME if your cross-slide is like mine. Check it out before you order
anything.

Good Luck,
DoN.
If he's making nut and screw, he COULD use a RH thread - the
cross-slide would just work backwards and take a bit of getting used
to (and the scale would read backwards)
** Posted from http://www.teranews.com **

On 2008-07-16, Bob Engelhardt wrote:
DoN. Nichols wrote:
... The nut was worn too -- but not nearly as much as the leadscrew.

!!! That's not good - it would be much better to have to replace the
nut than the lead screw. Or do you suppose that the nut had already
been replaced, perhaps more than once?

I suspect the nut was replaced many times.

This lathe came with a matching serial number bed turret and no
tailstock, and I believe that the longitudinal feed was almost never
used (the threading dial was in a drawer, and showed no signs of ever
being mounted), and that all threading was done using Geometric die
heads (or the like) in the turret.

However -- the cross-feed was used for parting off work
regularly, so I suspect that it had been through several nuts on that
one leadscrew. Nobody cared that the dial was not accurate, because
nothing was being turned to diameter with it. The precision turning was
done with box tools in the turret, so they just tossed in a new nut (the
cheapest part) to keep it working at the parting function.

I had to chase down a tailstock for normal use, though I do use
the turret for production runs of certain parts from time to time.

If not, do you suppose that the nut being softer had picked up steel
dust & had acted as a lap on the screw?

The nut (being bronze not brass) is not *that* much softer than
the mild steel of the leadscrew. I suspect that the lubing of the
leadscrew and nut was ignored more than the rest of the lathe, because
the lube point tends to get buried under chips.

Is this normal?

In a turret lathe used for production -- I think so. The next
replacement would probably have needed a new leadscrew as well even for
that function.

But the compound leadscrew has very little wear or backlash,
because that was ignored most of the time.

Enjoy,
DoN.

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On Jul 16, 10:11*am, Ignoramus30183 ignoramus30...@NOSPAM.
30183.invalid wrote:
...
I think that I will simply buy a dial indicator with a long stem. Kind
of a poor man's digital readout.

I don't depend on the dials on my lathe for accuracy. Take a cut,
measure the work, use the dial only to advance the bit. This works
well with HSS bits that can shave off half a thousandth.