Hi All,

We are running MACH4 on a custom machine. We have a ceramic extrusion axis with two motors, one for a plunger and one for an auger screw extruder. The plunger is a CNC axis (axis A) and the screw extruder is an out of band axis (OB1). We have been experiencing a fair amount noise/vibration, especially during circular movements.
After much experimentation I have realised that the vibration occurs when the OB1 axis is enabled but does not occur when the OB1 axis is disabled.
Does anyone have any experience with OB axes and have any idea why this might be occurring?

Alternatively, I suppose I could change the screw extruder from a stepper to a DC motor with ESC, since it is effectively running as a spindle and positional accuracy is not important, but I would rather not have to mess around with the hardware.

Thanks for any help 

how do you comand the OB! motor?

how do you comand the OB! motor?

Hi KatzYaakov,

We run a macro that pulls the rotational speed in Rev/s from a screen variable and sets the units, speed, and direction with mcJogSetUnitsMode, mcJogSetFeedRate, mcJogVelocityStart, respectively.

Cheers