Lead screw or thread dial not right?

Totally agree with you on wear as the machine is new. Not completely sure about the rebuild, things could have gone awry there, due to an error or some alignment of all the gear shafts, or there's still some hidden damage present. It's still detective work at this point... Best we can do is suggest some diagnostic tests that might give experienced people like you a clue.

Pardon my ignorant questions, but if the lead screw pin was broken, or the lead screw can move along its axis, couldn't that give different cuts in the work piece, or yield inconsistencies? I mean, something's wrong, so we can't assume everything is working perfectly.
Lead Screw pin was not damaged - the leadscrew itself was bent out about 1/4" - it would literally touch the inside of the split nut and rub.
 
@Jake M is saying what I've been saying. I just cut a thread on my PM-1340GT (no wear) which has an ELS and this is a 10 TPI thread @ 100 RPM and I ran it in 1.9" and just reversed the lathe as it has a VFD, the difference in the lines is the backlash. You fellows who don't have any backlash sure can save some time (if you don't have a threaded spindle) as you can thread in and out and do it in half the time.







@jareese When you installed your thread dial, did you have half-nut engaged, then sync the dial on a whole number?
Hmm.. I did NOT have the 1/2 nut engaged, nor did I make sure it was on a whole number...

**Edit -
Shouldn't really matter though should it? Even TPI leadscrew, Even tooth Thread dial...
 
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Check the tooth count on the threading dial. Someone here will know what it should be, just not Me.
It's 16 with a 4tpi lead screw. Both have been verified.
 
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