For the duration of time I've had my lathe, there's always been a "clunk" in the gear box. I've torn the gear box apart twice before to try and find it but never found anything. I had suspected a single gear in the past but couldn't find any issues with the teeth that would be causing issues. Until I noticed it was not turning true on its shaft. It is the gear on the selector handle.
I pulled it off and did my best to replace the brass bushing inside but it's the gear itself that's running untrue. At the time I had absolutely no idea how I set the gear up in the chuck and put an indicator on it to center it to return the bore. I believe I tried to indicate on the tip of the teeth but the gear is somewhat worn, so that was tricky at best. Not being able to indicate where the jaws were holding, I gave up for the fear of ruining the gear and rendering my gear box useless until I managed to find a replacement. Well that fear is still present even tho im a year further along with that much more knowledge, I'm still unsure how to approach this issue.
The only thing that comes to mind currently is to attach some kind of mount to the gear and hold that in the chuck, then indicate as best I can on the teeth, and clean out the bore.
The tips of the teeth aren't badly worn, but there are irregularities.
There are no other witness shoulders or rings on the gear I can indicate to. The gear was cast or pressed then the teeth made, so any shoulders do not run true.
I'm throwing my hat in the ring for ideas...
The lathe runs fine, but the more I work with it, the more I have a desire to fix up the issues that always irritated me. At some point, there's a pulley belt change needed. The bent must be lumpy and causes additional bumping/clunking. That's a spindle removal job..... Unless I get those build-a-belt... Can those take the same kind of torque a normal v-belt can?