[cp465vw]

I have a taig mill with the deepgroove set up. I created a circle on mastercam inches and my mill does move in a inch circle.
I am using mach3 mill

[project5k]

i guess i dont understand the question then, if you input an inch, and you got out an inch at the mill, wheres the problem, sounds like you already have the step calculation set up correctly...

[cp465vw]

sorry did not write the question right. ooops!
I drew a 4" circle and when it move the table it moves it much, much smaller.
I set a pen up yesturday and it seems to be about a half inch circle that is drawn by the mill. So i messed around with steps per in the motor tuning set up and got a bigger circle but still not 4". I am assuming that there is a calculation for steps per inch. I know the guy i got the motors has some where that it is 10 turns per inch. but how do I turn that into the calculation I need???
Thanks!!!

[Robin Hewitt]

Still a bit short on info for meaningful answers...

If you have ordinary microstepping drivers fitted, the switches on the stepper driver box determine the pulses per rev.

Multiply pulses per rev by the revs per inch and get pulses per inch.

[acondit]

Your basic useable stepper is 200 steps per rotation. Multiply that by how many microsteps (if any) your controller produces. Multiply that by any gear or belt reduction ratio (for direct connect use 1). Finally, multiply by the number of threads per inch on you leadscrew.
(200 x Msteps x reduction_ratio x TPI) equals steps to move 1 inch.