Help with compound assembly issue

[DiscoDan]

Ever since I bought my Craftsman 12x36 at an auction I have had issues with the compound feed screw and handle assembly. I have the parts manual and it looks like I have all of the correct parts. The problem is that when I assemble it the parts to the outside of the face-plate want to keep threading toward the face-plate, which then sandwiches the face-plate between the outside assembly and the collar at the end of the acme screw and then the whole shebang won't turn. You can see that there are obvious wear marks on the face-plate from before my ownership so it looks like a long-standing issue.

I believe I have the "commercial" compound. I have considered buying a different version that looks like it has different hardware that may assemble better. They aren't too expensive on that auction site.

Thoughts?

 

[mickri]

I just took mine apart. Two differences that I see in your pictures from my lathe. First the washer in my lathe is different. My washer is very thin, 0.0125 thickness, with a 3/8 id and a 7/8 od. The washer is not plastic and not metal. Don't know what it is made out of.



Second the order of the parts on my lathe is different from your picture.



On my lathe the assembly is the lead screw goes through the face plate. Then the thin washer goes on. Next you have the dial followed by the nut/sleeve that the slips into the dial as you screw it onto the lead screw. The nut/sleeve was not tight. As best as I can tell its purpose is to control the play between the lead screw, the face plate and the handle if that makes any sense. Next is the serrated lock washer, handle and nut. This nut was very tight. I had to use a socket to break it loose.

 

[DiscoDan]

mickri, that is interesting. Can you tell me what model lathe you have? I would like to see what your parts list shows as far as sequence of parts since the way you have yours laid out is different than mine. Specifically, the threaded nut (5th part from the right) is oriented backward from mine. If I assembled mine that way the numbered dial would no longer be next to the face-plate and would be on backward. And from my parts list the washer goes on the threaded nut against the collar portion of the nut.

FYI, my lathe is a 101.28940.

Never mind with the model number, I found the documentation and yours is exactly as it should be.

 

[DiscoDan]

It seems like there should be a way to lock the whole assembly to the shaft so that it can't keep threading toward the face-plate but I don't see any way to do that.

 

[BaronJ]

Is there not a grub screw in the sixth part from the right like in Micks picture ?

 

[DiscoDan]

No, there is no grub screw in anything. In the parts guides for other versions of the Craftsman lathe it seems like there is, but not in mine.

 

[BaronJ]

Hi Dan,
I wonder ! Would adding a grub screw help ?

From what I can see that threaded bit sets the clearance between the two faces and once set shouldn't move.

 

[pdentrem]

I was thinking that the shouldered bushing is or should be just a little longer than the dial and that washer is there to as a thrust washer?

 

[markba633csi]

There are two versions of this thing. One has the thumbscrew dial and the other (101.28940 for example) has the knurled ring arrangement. If you check the manual for the latter there is a factory procedure for setting the preload on the dial, but it is touchy. Clearly the thumbscrew design is less hassle. I have a 28940 also and while I was able to get a reasonable adjustment on the cross and compound dials, I am planning to tear into them both and do some massaging. Too many projects at the moment though.
Mark

 

[DiscoDan]

Issue resolved for now but the way this assembly is put together seems less than ideal. I may look for the other style since the are not real expensive. Thanks everyone.