Hello,

I'm running Mach 3 on my laptop and like the features and interface very much. Unfortunately I have a problem with my steppers, my setup is as follows:

- Aluminium CNC machine "frame" from ebay (kit without stepper motors and driver).
- Driver board and stepper motors are FET3 from Stepperworld with current limiting power resistors (the website has been shut down).
- PC has a 650MHz Pentium III, 256MB RAM (IBM T20) running a stripped down version of Windows XP.

Stepper World provides a program for testing their setup called VBStepDir. When I run this program at full tilt it runs all three axes smoothly in both directions apparently without missing a step. While doing this all motors sound extremely smooth and have a consistent hum to them.

I'm configuring the motors on Mach3 and I get a very rough sound coming from the steppers, and they are definitely skipping pulses. This is the case for all 3 axis. If I switch back to VBStepDir everything seems fine and it will lower and raise perfectly smoothly again.

I have played around with the velocities, acceleration, pulse widths (all the options in the motor tuning menu)
I have reinstalled a newer version of mach3 after that on my computer but the problem still persists.

Any help will be greatly appreciated.

Regards,

Stephane