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Spindle bearing issues - cast bearing


Sep 9, 2022
Hey folks,
I mentioned in my first thread that my lathe wasn't taken care of the best.
The rear bearing is great, but the front bearing has significant grooving.
Personally, I'd like to hit both the spindle and the bearing with 800 or 1000 grit to help smooth the surface. A friend said given how little I'll be relying on this machine, just run it as is.
Do you guys have any advice on what to do?



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Feb 23, 2016
Houston, TX
Considering the age, that's not uncommon on chuck side. I'd clean the shaft to attempt to get high spots down.

And with new felt and new oil, clearances set correct, it will operate very nicely.

Early on in re-assembly, try to get the end thrust set reasonably close. That will sort of get high spots on shaft back to mating with low spots of bearing bore, and will spin nicer.

Again, new felts and oil. And I'd aim for .001" to .0015" on oil clearance of the two bores. Checked and adjusted using a pry bar to lift up and down, with dial indicator reading at 12 oclock each side. Set with shims.

End thrust I like .0005", but .001" wouldn't break my heart.


Jun 28, 2012
Mt Clemens, Michigan 48035
Sometimes I think a really good cleaning, being sure oil getting where it should and felts restored is a good plan. I don't see what adding abrasive to the bearing would do any benefit.
But I'm not the lathe guy here.
Guess I might run a hard India stone over to take off any highest places.


Sep 9, 2022
Thanks guys!
I didn't mention that my whole reason for digging into the bears was I had .010 to .012 in radial spindle play on the chuck side. I didn't measure the gear train side before teardown.
After only cleaning everything up, I was able to get the back bearing to .002 and the front bearing to .007 of play. I had to remove the .004 shims on either side of the spindle bearing, and add one .001 shim that I had to make to the gear train bearing. After that, I lightly clamped, set the thrust play at 7 or 8 tenths. Then loosened and tightened the bearings with a torque wrench to 15,20,25, and stopping at 29 or 30.
Now my axial spindle play is between .0015 and.002 for both spindle bearings.

I was thinking about removing the next shim lamination, but at .002, I'm afraid I would need to make my own .001 shims to give me my clearance back, and I wasn't up for the task yet.