Bought a used lathe, Sheldon 10". It's in really good shape other than being encrusted in 3 decades worth of crud from sitting. I'm new at this BTW, so still pretty clueless.
2x non-elbow grease issues noted;
(1) Had a 1" drill bit chucked in the tailstock, frozen in place. Pulled the tailstock spindle, gently tapped the bit (chuck and all) out with a tie rod puller. Predictably, they'd spun the bit and galled the shank (and spindle). Solution? My guess is to re-ream the spindle to MT #2. Y/N?
(2) Excessive backlash in the carriage. On examination, they'd ran it with the bolt that goes into the cross-feed nut loose. Bolt itself is worn. Work the carriage crank, watch it flop around. This brings up multiple sub-issues.
(a) It looks like it's the wrong bolt. It's fully threaded, the wear is on the threads. Looks to me like this should have a bolt with a shoulder where it goes through the top of the lower slide and threads into the nut. Y/N?
(b) Should the new bolt (shouldered or not), be hard or soft? My guess is about a grade 5. Not too hard, not too soft. Or is hard better, as long as it's properly tightened and not working back and forth on the threads?
(b2) Wouldn't a spring washer on the bolt help take up play?
(c) The threads in the cross-feed nut (the bolt threads, not the feed screw) took some damage. I'm pretty sure, run a bottom tap through it, keep it tightened properly, it'll be a non-issue. Do that, fix the rest, see how it goes? I'd probably have to have a new cross-feed nut made. Parts for Sheldons seem to be thin on the ground.
(c) How much wear is acceptable in the cross-feed nut? There's noticeable (1-2 degrees/1/32") play when I rock it back and forth on the feed screw. Almost zero play trying to work it along the axis of the feed screw (like it would work being cranked).
(d) The end of the feed screw rides in a hole in the carriage. Call it a 1/2" hole, with the end of the feed screw being 1/4". It just flops around in there...shouldn't there be a bushing for the machined end of the feed screw to ride in? Seems to me, being unsupported, is going to magnify the effects of cumulative wear in the entire carriage assembly. Haven't found a parts list for my specific machine. One shows nothing. The other shows a collar with a nut. Any reason not to put a bushing in there, put a set screw in from the top to lock it in place? Or does the feed nut provide the support?
Thanks!
2x non-elbow grease issues noted;
(1) Had a 1" drill bit chucked in the tailstock, frozen in place. Pulled the tailstock spindle, gently tapped the bit (chuck and all) out with a tie rod puller. Predictably, they'd spun the bit and galled the shank (and spindle). Solution? My guess is to re-ream the spindle to MT #2. Y/N?
(2) Excessive backlash in the carriage. On examination, they'd ran it with the bolt that goes into the cross-feed nut loose. Bolt itself is worn. Work the carriage crank, watch it flop around. This brings up multiple sub-issues.
(a) It looks like it's the wrong bolt. It's fully threaded, the wear is on the threads. Looks to me like this should have a bolt with a shoulder where it goes through the top of the lower slide and threads into the nut. Y/N?
(b) Should the new bolt (shouldered or not), be hard or soft? My guess is about a grade 5. Not too hard, not too soft. Or is hard better, as long as it's properly tightened and not working back and forth on the threads?
(b2) Wouldn't a spring washer on the bolt help take up play?
(c) The threads in the cross-feed nut (the bolt threads, not the feed screw) took some damage. I'm pretty sure, run a bottom tap through it, keep it tightened properly, it'll be a non-issue. Do that, fix the rest, see how it goes? I'd probably have to have a new cross-feed nut made. Parts for Sheldons seem to be thin on the ground.
(c) How much wear is acceptable in the cross-feed nut? There's noticeable (1-2 degrees/1/32") play when I rock it back and forth on the feed screw. Almost zero play trying to work it along the axis of the feed screw (like it would work being cranked).
(d) The end of the feed screw rides in a hole in the carriage. Call it a 1/2" hole, with the end of the feed screw being 1/4". It just flops around in there...shouldn't there be a bushing for the machined end of the feed screw to ride in? Seems to me, being unsupported, is going to magnify the effects of cumulative wear in the entire carriage assembly. Haven't found a parts list for my specific machine. One shows nothing. The other shows a collar with a nut. Any reason not to put a bushing in there, put a set screw in from the top to lock it in place? Or does the feed nut provide the support?
Thanks!
Last edited:
