Brass ACME nut repair

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.
I was thinking about fixing this.
Three things come to mind.
1) Buy a McMaster ACME brass nut 95270A123 and attach it to a custom made part to fit under the cross slide.
2) Do something clever like wax the screw and inject epoxy into the nut to take up the slop.
3) Make a replacement part on the mill and lathe.
Has anyone dealt with this issue. Clausing wants $750 (not a typo) to custom make this part for me.
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Is it something you can take off, measure up and have someone make for you for less? If they did this, would you be guaranteed to have less slop?
--


Regards,
Joe Agro, Jr.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I can take off the part and mail it to whoever to replicate. I would obviously pay for it, but not anywhere close to $750, of course. I looked at the nut, it looks badly worn, I do not think that it was this way originally -- but, surely I would have to ascertain that again. I may be able to do something with my mill, original nut, and the McMaster nut. (as in, mill out the original nut, insert the mcMaster nut and braze in)
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Ultimately, what could happen is that the McMaster is too loose or too tight and then you are almost back at square 1... But it's worth a try compared to $750!
--


Regards,
Joe Agro, Jr.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I think that I will buy one today.
i
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You can always return it if it doesn't fit the lead screw properly BEFORE modifying it.
If you are going to braze it in, think about getting a piece of spare male thread to put in it to make sure it holds size during the process. Don't know if that will help or not in an overheat situation, but it's low cost insurance.
Regards, Joe Agro, Jr. (800) 871-5022 01.908.542.0244 Automatic / Pneumatic Drills: http://www.AutoDrill.com Multiple Spindle Drills: http://www.Multi-Drill.com
V8013-R
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 14 Jul 2008 11:41:55 -0400, "Joe AutoDrill"

I read posts like this frequently but in reality any machine tool built before the advent of ball screws had backlash in all its adjustments. Apprentices were taught to cope with this problem by making all adjustments in the same direction - opposite to the force being applied by the cutting tool. In your lathe's case, assuming normal turning operations, you back the tool off and then readjust it toward the work until you reach the dial setting you had used for the previous cut and then as much more as you want for the next cut.
If you want less slop then just make a new nut.... after all, you've got the lathe to bore and thread the new nut.
Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You can adjust the cross slide in the opposite direction if you pull it by hand to "aid" it's motion.
i

--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

    [ ... ]

    And -- one thing which you can do is to mount a dial indicator with a two or three inch travel so it measures the motion of the cross slide. This will be more accurate than a worn leadscrew in a worn nut. (If it were just the nut worn, you would have the same backlash all the way through the range, and your dials would be accurate enough. However, if the leadscrew is worn, that will be more so in the middle of the range, and will introduce extra errors -- unless you are measuring cross-slide travel with something which does not depend on the leadscrew.
    My 5418 had the leadscrew and nut so badly worn that it was producing 0.070" of backlash in the middle of travel -- and this on a 1/2" diameter leadscrew which produced a full 0.100" travel per rotation when in good shape.
    However -- the leadscrew and nut were a lot less expensive for mine -- at least back when I got it. :-)

    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.
--
Email: < snipped-for-privacy@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

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)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
"Ignoramus22312"
message

You can also buy the appropriate acme tap and make a new nut.
The nut part number you list above is for a right-hand nut. You might want to take a closer look at your old nut/screw---most I've seen are left-hand.
Bill
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

$150
Good point, I think that you are right.
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Jul 14, 11:36am, Ignoramus22312 <ignoramus22...@NOSPAM. 22312.invalid> wrote:

i deal with it by ignoring it. There's no climb-milling issue on a lathe. Look into Moglice
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What about facing?
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Jul 14, 2:06pm, Ignoramus22312 <ignoramus22...@NOSPAM. 22312.invalid> wrote:

The free play on my lathe is 0.052" on the cross slide, 0.038" on the compound. The compound at 29 degrees would be more likely to slip forward and dig in if the tool had a large top rake, but I know better than to grind it that way. A top rake of 10 - 20 degree doesn't cause problems. I tried 60 degrees once after seeing it in an old book and did have trouble.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Jul 14, 2:06pm, Ignoramus22312 <ignoramus22...@NOSPAM. 22312.invalid> wrote:

What about facing?
John Martin
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 14 Jul 2008 10:36:05 -0500, Ignoramus22312

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

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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

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.
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

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.
Mike
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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.
--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.