dip switches are all the same (I adjusted them from 16micro steps to 8 yesterday).

Mach3 is latest version from Mach3 website.

Will try a different cable (I'd like to dismiss this, but my given one failure of deduction already I'm more open to testing).


I got the graunchy sound (which I thought was ballnut, but now think it is motor caused) also when using Gcode. I haven't cut anything yet so don't know about circles.

I just ran my tests using the X and Z outputs from the BOB (alone with no other connection) and got the same result, ie the fault only occurs when using driver2. different output from BOB also means different keyboard key and different pin on parallel port, so tends to rule those out as cause.

Defect appears to be in driver2 and maybe also BOB? I can't work out how pressing eg Y axis (with no driver connected) can cause problem on X axis, other than the BOB also being at fault.

I'm about to put the gantry back on and try driving X and Y using drivers 1 and 3. Which hopefully should work.