Hi,
I am in the process of converting a Proxxon mill to a CNC machine. I have 3 stepper motors(57BYGH56-401A), a controller card, a 24v power supply and Mach 3 running on a windows XP box.
But I have a problem.
The Proxxon mill has an M5 drive which means that one rotation is 1mm. I am trying to calibrate the motors on the bench prior to fitting them to the mill. I am looking for 360 rotation and adjust the steps setting on Mach 3 until I get a decent result for a 1mm jog. Then I up the jog to say 5mm and see how close to 5 rotations I get - then adjust the steps setting until I get close to 5 rotations. Then up to 15 rotations, 25 rotations and finally 100 rotations. I can get close to +/- 5 degrees for 100 rotations. Then I can make a slight adjustment to the steps setting and all goes haywire. Suddenly I'm out about 10%. I have tried adjusting the microstepping values, the acceleration and velocity in Mach 3, a different computer, swapping stepper motors, altering the current setting on the controller board, monitoring the power supply - its always the same. About 30 minutes calibrating and then - start again. I'm beginning to lose my remaining hair. Are my stepper motors rubbish? - the controller board is based on the TB6560AHQ chip and is from China. Am I expecting too much? Before I start buying new stuff some advice would be very, very gratefully received.
Thanks.
Richard