Hi , i can only make thread in millimeters 2, 2.5, 3, 8, 10, etc but when i put in the wizard step of 8.4666, ie TPI = 3 P = 1/3 = 0.3333, is done with a pitch of 8mm, if i put 8.5mm then make 8mm, if i put 9mm also make 8mm, recently if i put 10mm then is correct in 10mm.

 i canot make threads with pitch in inches, I'm using version 043,062.

This is some bug in the threading.

regards
Renato

Works fine for me as I occasionally do imperial threads and just convert to metric and enter that as the pitch.
 Sounds like that is what you are doing?
Does the code produced by the wizard show the pitch you want or the pitch you say you get?
Hood

Hi Hood, the problem was the frecuency of 35khz,, if put 45khz then the pitch is correct 8.46666mm/rev. With 35khz the parameter P=8.46666 but in the DRO show 7.97mm/rev.

Another concern if the commanded speed is 250rpm but the speedometer shows 260rpm, this could affect the pitch of the thread?.

thanks
Renato

The commanded speed is of no real concern as Mach looks at the true RPM and threads accordingly. So as long as your True RPM is actually good then it will be fine.
One other thing to watch may be the Feed Override, I think it should be ignored if you are using the parallel port but iI know if using the SmoothStepper the FRO will affect the threading so you need to make sure it is at 100% for it but as said I dont think that is an issue with the parallel port. For the Smoothstepper I call a M49 before a thread and a M48 after, that way the FRO is ignred for the duration of the thread.
Hood