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Compound Bushing BINDING on Compound Screw

silver star

Aluminum
Joined
Sep 19, 2013
Location
OK USA
New Guy Here to my South Bend 10" 4 1/2' bed.
I am cleaning everything south of head stock while I am waiting for electrician.
I have the Taper Attachment/Saddle off, apart, cleaned and going together.
I would like to think I am mechanically apt because I can rebuild any muffler bearing but...here is my question.

I am trying to adjust compound screw to turn free when bushing is tight to housing.
When I tighten bushing, shaft binds.
I have tried shaft in bushing when out and in my hands, smooth without binding. I have rolled on glass top to check for bent shaft, I have checked face of compound where busing mates, seems true, I have loosen rest nut and measured shaft OD and bushing ID.

Can someone advise me please what is going on.
PS, I did search here and there is a ton of stuff but I'm not finding this problem.
Thanks,
Michael
 
Yup, that stopped the binding.
So let me take this up a notch.
I have found on this forum a modification or more specific;
Revival & Improvement of the 10L Crossfeed Taper Screw, by TJ Schmidt.
Is there a similar improvement for the compound screw.
It still is not as user friendly as I think it can be.
Thanks
 
As the compound wears with use, it shifts away from the gib, which tends to bind the screw.You might find a slight 'relocation' of the nut to cure the problem. It is not designed to be 'user friendly' it is designed to be fixed by a machinery repairman with years of experience :)

allan
 
Thanks for reply.
I did not intend "user friendly" to apply to the repair, rather the rotation of screw in & out. It still is a chore.
Thanks again.
 
Diagnose the problem:

Remove the screw and bushing from the compound.

Shift the compound slide so the nut is as close to the bushing as possible, snug the gib.

Insert a shaft into the compound nut, sized to be a snug fit into the minor diameter of the
somewhat worn nut.

The shaft should extend out of the front of the assmbly in the exact center of the threaded hole
for the bushing, and directly in line with the direction of slide travel.

If it is offset in either plan (up/down or left/right) then that is your problem and the screw will bind
then especially at the extreme close end of the travel.
 
Thanks Allan & Jim.
I understand and can see where you are coming from.
I will go this route and update.
Wish you guy's an easy Labor Day weekend.
 
We have good news.
Like, OMG!
Homerun!
First I turned the brass rest nut around, no help.
Then separated compound top from the swivel.
Cleaned and sprayed blue lay out on top and bottom contact surfaces and rubbed one side at a time. Watching some YouTube scrapers helped me there a bit.
Then looked at the gib.
It looked rough to me, for something that slides.
So in the vise it went and went at it with 400/600 then 1200 grit sand paper using a file for backbone. I think that helped some.
But I think where the bulk of the resistance was is where the top face met the bottom face. With the file I located nicks or hi spots. Knocked them off and did the sand paper thing, cleaned, oiled, put together and adjusted gib and feels good enough to be new for me.
I mean really nice, I mean very user friendly.
Thanks!
 








 
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