stoneaxe
Stainless
- Joined
- Mar 2, 2010
- Location
- pacific northwest
The compound on my lathe has had issues. It was tight when retracted, and got looser when extended. Sounds like a taper, yes? Anyway, I pulled it off, and set it on a surface plate with blue- it was printing just on the ends. So I scraped it flat, took very little to do so.
Put it back together with no other surfaces scraped, and it seems to leave a mostly even contact on the mating surface- not great contact, but more or less even end to end.
now it is slightly looser on each end than in the middle of it's travel range, when sliding it by hand-no leadscrew. Put together ,with the leadscrew leverage, it is hardly noticeable.
So the thread title- for some reason, the compound extends easily and smoothly, but gets sticky when backing it up- and not evenly, but with a partially smooth rotation, then a stick, then easier for the rest of the rotation. Like you might feel with a bent leadscrew, but only in reverse.
At first I figured the gib was loose, and when the leadscrew is backed out, the gib is wedging. Nope.
Then I backed off the thread dial, to make sure a bent leadscrew was not camming the dial against the housing every half rotation. Did not help.
Next I am going to pull out the screw and check the shoulder where the thrust bearing sit and see if there is something going on there.
Any other suggestions?
Put it back together with no other surfaces scraped, and it seems to leave a mostly even contact on the mating surface- not great contact, but more or less even end to end.
now it is slightly looser on each end than in the middle of it's travel range, when sliding it by hand-no leadscrew. Put together ,with the leadscrew leverage, it is hardly noticeable.
So the thread title- for some reason, the compound extends easily and smoothly, but gets sticky when backing it up- and not evenly, but with a partially smooth rotation, then a stick, then easier for the rest of the rotation. Like you might feel with a bent leadscrew, but only in reverse.
At first I figured the gib was loose, and when the leadscrew is backed out, the gib is wedging. Nope.
Then I backed off the thread dial, to make sure a bent leadscrew was not camming the dial against the housing every half rotation. Did not help.
Next I am going to pull out the screw and check the shoulder where the thrust bearing sit and see if there is something going on there.
Any other suggestions?