Shop Fox M1049 Tailstock

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imagineer

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The tailstock on my Shop Fox M1049 lathe is just about locked up. I'm fairly certain the problem is the ram (#451) is, for some reason, sticking in the tailstock body (#463). It takes a significant amount of force to turn the handwheel to get the ram to move outward. However, the handwheel (and I assume the lead screw) both turn easily for 3/4 of a rotation when reversing, but as the lead screw starts pulling on the ram, it gets just a difficult to turn the hand wheel.

This problem didn't exist when I first got the lathe, but seemed to get worse, quickly. The lathe is fairly new and hasn't seem much use, and I made sure to squirt oil in all the oilers before 1st use.

I'll have some time this coming week to try and disassemble the unit and diagnose the issue. Looking at the attached diagram, am I correct in assuming that part #459 (set screw) rides in the slot in part #451 (tailstock ram), preventing it from rotating? I want to make sure there isn't a key inside, or part of, the tailstock body before I start forcing things.
 

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I would say you are correct about part #459. Silly question, #459 isn't too tight is it?
 
Any change if you loosen #469 and then #462?
 
Another wonderment, there isn't by chance two #458. One below the tail stock ram and the one you already removed?
 
All good questions...
Removing the handwheel doesn't seem to improve anything.
I suppose there could be a 2nd set screw, but I don't see another keyway on the bottom side of the ram.

I'm guessing there's some Chinese grit or grinding debris that was left inside the tailstock body that's causing the problem. The plan is to remove the handwheel and all other external parts, then position the assembly vertically in a hydraulic press and try and push the ram out from the handwheel end.

At this point, its unusable, so if I mess it up I haven't lost much.
 
I'm out of guesses. Was hoping that someone would chime in and say they had the same problem and how they fixed it. I will keep thinking on it too.
 
Fixed it. It required a hydraulic press to take it apart. I was expecting to see some linear mark or scoring on the ram (#451) to indicate what was causing the tailstock to stick, but there wasn't.

After full disassembly and cleaning, I found that the ram would insert into the tailstock body (#463) only about 1/8" before getting stuck. When I tried inserting the ram backwards, i.e., Morse taper end in first, the ram inserted about halfway before getting stuck. This meant the problem wasn't with the tailstock body.

I measured the ram with a 5 place digital micrometer and found the threaded end was .00035 to .00050" larger diameter than the Morse taper end. I chucked it in the lathe, and using #800 grit wet/dry paper a flat plate and and machine oil, managed to "stone" the ram such that it fit the tailstock body with minimal friction.

Then I found there was rust in the bore for the clamp shoe (#458). This was probably preventing the clamp shoe from backing off when the level (#457) was loosened. I cleaned up the bore and the clamp shoe, and when reassembling, I added a small spring under the clamp shoe to ensure it moved upward when the lever was loosened.

Last, I found the bushing (#454) had small burrs on the inside of the 10mm bore and was probably dragging on the lead screw (#453). I drilled out the bushing using a "X" size drill bit (.397") to clear the burrs.

It's back together and works perfectly.
 
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