Never tried or used the macro. Based on my poor programming skills, my"guess" is as follows:

The threads as straight line segments NOT arcs, so the resolution is how closely the length of many straight line paths would be fitting inside / outside of 360 degrees of a diameter.
Thanks Rich,
actually I am not trying to cut thread, I want to cut a cone hole of 1.75" large side at high of 0.5" at angle 2.
I can't find any way in Mach3 to do it.
would you please lead me some new ideas?
Best
Adam