Quote Originally Posted by Jonathan View Post
320 step/mm * 2000 mm/min = 640,000 step/min
640,000/60=10.67kHz
10.67kHz is less than 25kHz ... so that shouldn't be a problem.
Jonathan I was more concerned that the Kernal speed was set too high which can cause strange happenings like this.!!. . . Long shot but it happens.

Andy.

First are you 100% sure there's no mechanical issues.? No binding etc. It won't take much stickage at these speeds with such low powered motors/drives to rob torque.

If not then next try cutting the same part but in air without spindle running. This will eliminate VFD/Spindle interference.

After that then carefully inspect wires at the motor connectors and at the BOB/drives for any lose connections.

The drives are better than some of these machines but still cheap low quality drives. That said they should do this job thou with just 24v you can't expect too much.

Again I'm clutching straws here but you could try setting the micro stepping to 400 on drives and see if it changes anything. Just do the problem Axis first to see if it alters any thing.
You'll need to go into Motor tuning and set the Steps Per to 80 and retune the motors. You'll see can get much higher velocity on that axis now but I wouldn't anyhigher than you have it now.

Failing any of this working and machine being mechanicly sound then scrap it all and get this MX3660 - 3-Axis DSP Based Digital Stepper Drive Max 60 VDC / 6.0A along with 48V PSU.
It will transform the machine and I'm pretty sure it will fit neatly into your existing box with only slight modification. It comes complete with Digital drives, built in BOB and Spindle speed control.
Rated upto 60V 6A and will easily run motors at 50-55Vdc with a unregulated PSU so if you want to upgrade motors to say 3nm at a later date then you can. . . . .Or take it with you to another bigger machine.!!