[Lathe] New to me Yangzhou TY-CO632 13x40 Gear Head Lathe.

I pulled the screw and nut back out of the machine this morning. I measured the OD of the screw at both ends and near the middle. It was about .002" larger at the end where the nut was sticking. I ran a file over that end while the screw was turning at about 300 rpm until it was the same diameter as the middle. Then I used a small triangular file to clean up the threads and that area. I adjusted the nut so that there is only about .005"-.010" of backlash and the nut doesn't get tight anywhere on the screw now. Once the screw was taken care of I worked on the cross slide gib adjustment until I could slide it all the way back and forth without any binding. I hooked the nut back up to the cross slide and there is almost no perceivable backlash and it doesn't bind up at any point in its travel.

Thanks to all of you for your help.
 
Over the weekend I was trying to turn some steel and I found that even the lowest feed rate was too fast at .0036"/rev. I decided to dig through my box of gears and come up with a lower feed rate. I put a 30T on the shaft closest to the spindle. I mated it up with the 127T gear. Then I put a 66T on the gear box shaft and mated that to the 120T gear. That should reduce the feed to .429 of the normal rate. .0036 x .429 = .00154". That seems more reasonable.

I also noticed for the first time that the feed and threading charts say that the lead screw is 8TPI but the gearing shown seems to indicate that the leadscrew is actually metric. I've been threading imperial threads with the 40 x 120 x 40 gearset, but it looks like I should have been using the 40/120 x 127/40 transposition gearing.

According to the charts you need three completely different gear setups for normal feed, imperial threading and metric threading. WTH were they thinking?
 

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Over the weekend I was trying to turn some steel and I found that even the lowest feed rate was too fast at .0036"/rev. I decided to dig through my box of gears and come up with a lower feed rate. I put a 30T on the shaft closest to the spindle. I mated it up with the 127T gear. Then I put a 66T on the gear box shaft and mated that to the 120T gear. That should reduce the feed to .429 of the normal rate. .0036 x .429 = .00154". That seems more reasonable.

I also noticed for the first time that the feed and threading charts say that the lead screw is 8TPI but the gearing shown seems to indicate that the leadscrew is actually metric. I've been threading imperial threads with the 40 x 120 x 40 gearset, but it looks like I should have been using the 40/120 x 127/40 transposition gearing.

According to the charts you need three completely different gear setups for normal feed, imperial threading and metric threading. WTH were they thinking?
Hi Chris
I realize this is a pretty old post, But I have the same lathe and it's not in as good shape as yours. I have a lot of similar issues. I'm in the process of a complete rebuild and my plates are almost illegible. I was wondering if you had pictures of any of the other plates. Specifically the Indicator plate on the side of the carriage?
Thanks Steve
 
Resurrecting this old thread yet again. I just got the same model lathe, but it doesn’t have the pilot light, e-stop and jog buttons on top of the headstock. I’m sure I saw a thread where someone added these to a similar machine but I can’t find it now. Can anyone point me to such info?
 
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