well thanks for your time in helping me dude.. appreciated

no time right now to chase this one but have to cut a super dense part tomorrow night.. i think if its gonna freak it would be then.

didnt solve that issue but kernel stepping solved.

uploaded this vid of probes for a mate.

small success but its a start in the right direction

http://www.youtube.com/watch?v=6SFxLRWyyL4

posted on 3dcadjewelery re this issue and got this response  (some few other jewellers have had same issue it seems, and all solve it by switching off toolpath display.

I have had this issue before! and yes, turning off the display window solves it.

But lets break it down a bit. nd I will give you WHY its doing it........

X Y and Z have a ratio of 10 to 1 (without the microstepping) so at a given speed in motor tuning, the stepper motor has to rotate at a certain RPM to reach your motor tuning speed. So to rotate that certain speed, the computer has to put out so many pulses.

The A axis gearing is MUCH MUCH higher. 72 t0 1 I believe. So the computer has to put out alot more pulses to reach the motor tuning speed. It is hogging processor power. And believe it or not there is quite a bit of processor power needed to also rotate the model in the toolpath screen. I have a p4 2.8 with 2 gigs of ram, and I still get that on large files.

any clues?

im prepared to live with this "error" if its simply a case of processing power.. only chasing it in case its a simple tickbox correction somewhere

It is likely to be  CPU/Graphics issue, at the moment the way Mach uses the toolpath takes a lot out of Mach but in the next revision this has all changed and the toolpath is entirely seperate and will probably help in your situation.
Hood

cool.. thanks guys...