I'm going to be threading the tenon of a rifle barrel and am practicing
on a 1" dia piece of scrap crs. The thread is 16tpi, standard 60 deg. With
the compound at 30 deg., 60 deg. threading tool square/centered to the stock
I keep getting an uneven finished thread. The left side of the "V" is about
20 deg. and the right side about 40 deg. If I advance the cutter using only
the cross feed, and not the compound, I get a perfect thread.
I've tried setting the compound at 29.5deg, 30deg, etc. with no
improvement. I've checked the set-up with a protractor, dial indicators,
etc. and can find nothing wrong with the lathe or my set-ups. Obviously
something is wrong but at this point I don't have a clue. Any suggestions?
Thanks...Jon.