I have been working for several months trying to get faster Z Axis movement out of a knee mill conversion, I am driving the knee.
I am using a Nema 42 stepper motor, I would like to get 15 - 20 in/min
The motor will move the knee ok, but when I try to calibrate with Mach3 I have to slowdown to 2 in/min to get the right steps?

Any suggestions
Thanks