- Joined
- Dec 27, 2013
- Messages
- 124
Another take is to never disengage from the lead screw until the thread is finished. Probably the best course of action for a metric thread on a G0602. This technique has worked extremely well for me.
You will want to check the reversing mechanism on the lathe. If your reversing system reverses the drive from the motor to the spindle (highly unlikely, since modern lathes reverse the motor rotation) you wold be OK.This is going to work. I marked on the dial and the outer ring. I marked the carriage position. I moved the carriage until the dial complete one revolution.
I then marked the carriage position again. It measured out to be exactly 2 inches travel. I moved the carriage all around and when I stopped the carriage on the marks on the bed the marks on the dial always lined up.
I chucked up some stock and tomorrow will set up the change gears for some thread cutting.
After reading the posts about not disengaging the halfnuts and running it through the tests I did realize that this thread dial is unnecessary as there is a lever that allows me to reverse the travel of the carriage with out stopping the lathe.
At least it was a fun project and it's there as option if I need it.
It also allows threading to a shoulder. You can do so without disengaging the half nuts but you would have to stop the lathe early and finish the thread by hand turning the spindle.I think the thread dial is mostly used as an optimization for doing threading, to do it faster. Running the lathe in reverse for the threads probably takes longer than just releasing the half-nut and cranking it back by hand, then tightening the half-nut and lining up the dial to the right spot.