Investigating spindle runout on my Seneca Falls Star 30 Lathe.

[Bob Korves]

First, vet the spindle to lathe interface, with the chuck removed completely. Get that correct, minimal runout in the bearing to spindle fit, end play as well. Then check the spindle for running true at the threads and the register surfaces. Get that running correctly. Then mount the chuck and work on it. First, get the chuck body to not have play on the front and rear faces, then on the front and rear of the outside diameter. Finally, check the jaws for problems. You must do the work in this logical order or you may be causing more new errors than fixing existing ones. You must also keep the carriage, cross slide, and ways out of the equation. Additional possible sources of error only confuse and confound the issues.

 

[matthewsx]

Beyond my capabilities at the moment. I could probably make the basic plate okay, but doing the internal thread would be a no go.

I bought a tap to do the threads on my 4 jaw.