Triac PC Backlash

[blatter]

I have been trying to get rid of the backlash in x and y, i have checked and adjusted the Gibs on both axis that has removed some but cutting a circular boss i am still getting a 0.1mm error.
i have noticed in VR milling 5 machine settings there is an option under the feed section to add backlash values. is this enabled as playing with the figures dosent seem to make any difference.

thanks

Paul

[Steve]

The backlash parameters are inactive on this machine. They were specified in the setup for further use.

An error of 0.1mm is too large to correct you should inspect the machine and find where the error is coming from.

Put a clock on the end of the ballscrew and jog backwards and forwards to see if the screw is correctly secured at the ends. there should be no float in this. check the ballscrew nut is secure to the slides.

I am not sure if the ballscrew is belt driven or a direct drive but try turning the motor and see if the ballscrew turns at the same time if not either tighten the belt or check the pullys are fixed securely to the motor and the screw.

If the backlash is in the Ballscrew Nut then it would require a new ballscrew.

You need to find where the backlash is comming from. Is it in the Coupling of the motor to the ballscrew, the ballscrew mounting bearings or the ballscrew itself?

[blatter]

Thanks Steve, will have a look with a DTI and see what i find. will let you know the results.

Paul

[Martin]

The most likely place to look is the tab nut. The pulley on the leadscrew will have a keyway & the pulley on the motor should have 2 grub scres or be pinned. It would be unusual for either to cause a problem. All 3 axis are belt driven.
Have you checked the Jib strips & adjusted. It may be that the slides are loose & therefore stalling. You would get the same results if the slides are tight.