Stability of the zero point.

[andrejculk]

I have a problem with the stability of the zero point.
The zero point is unstable.

The machine Fadal VMC 4020 we began to move the zero position. From piece to piece, the zero point is the following X and Y-axis up to 0.03mm. This began to happen suddenly. What could cause this?

[Scanfab]

Are you using a solid stopper to run your part against, it doesn't bend by 0.03mm when you tighten part? Can you put a dial indicator on the spindle and measure the movement of the table(put tip onto side of vice)-you can push alone in x direction, or with a friend to see if there is movement of 0.03mm or more. If there is, maybe you need new thrust bearings which cost 100 USD.

[Neal]

If your part is held tight and not moving, then I would check the mechanical system for lost motion. I.E. Gibbs straps, motor to ball screw connection, and ball nut to ballscrew play and thrust bearing end play.
Out side possibility of motor feed back variation.

Neal

[andrejculk]

Thanks for the response. But perhaps even error binding. I'll report if I find the mistake. I hope that is binding, and not the machine.