I have a Taiwanese Jet 1024 lathe. When everything goes right, I've managed to cut nice threads. But on two occasions, I've had a strange problem that I can't understand.
I'm cutting an external thread, towards the headstock. I make a pass, back out the compound, run the motor in reverse a good 1/4 inch past the beginning of the thread, turn in the compound and make another cut.
Twice, about halfway through, the halfnut lever popped out, probably when I reverse at the end of the cut. But that's not my problem. If I run the spindle until #1 comes up on the halfnut dial, (where I set it when I began), engage the halfnut lever, and try to get back into the thread, the cutting tool is nowhere near the vee of the thread. How can this be? I'm cutting 20 tpi, nothing tricky there, I just can't figure out why I can't get back into the thread.