unfortunatly i only use Trapezoidal ball screws and rubbish brass Trapezoidal nuts for my cnc machine...

I know its not ball screw and i know the accuracy will be lower!

I have eleminated any movement from the steper motors/couplings, these now sit flush againts a bearing either side of the mounting

i still have a lot of backlash im gussing from the Trapezoidal set up i have...

i 'guess' i could add another Trapezoidal nut to each axis but i dont want the machine to be too tight...


i have a dial indicator and have looked at the backlash feature on mach3 but i want to know the best way to record the actual backlash...


do i set a zero on one axis, jog around and the send it back to zero and record the difference? or is there another better way!?

Thanks all!

Cosha

i want to know the best way to record the actual backlash...

Just move the axis in one direction to remove any backlash, now move in the same direction...say .5", then go back a .5".
If there is backlash you will not have gone fully back and the actual distance traveled is per your indicator. The difference is the backlash.

You could also just move in one direction to remove the backlash, set the indicator to Zero, then move ion the oposite direction by step jogging in increments of say .0001"
and note how many jogs it took to just get the indicator to show movement.

Make sure your steps per unit are correct before doing the above.

RICH