Messages

1

General Mach Discussion / Re: Drifting in the Y axis

« on: December 18, 2009, 03:19:34 AM »

Thanks everyone for your input. Just to answer a few questions, the PC is a dedicated and high powered machine. It has just the OS (XP) and Mach3 on it and is not connected to any other device.
I did some testing a while ago and if I zero Y to something solid then move + & - in Y a few times and check Y again I can see it has drifted + in Y. Thing is it's fairly repeatable and only appears to loose steps in the -Y direction but not the +Y. I've cranked the Y axis by hand and it feels fine. I've checked the backlash and it's 0.02mm, which is fine. I'll check the couplings and any other fixings I can find. Thanks again.

Rob

2

General Mach Discussion / Re: Drifting in the Y axis

« on: December 17, 2009, 08:52:39 AM »

Thanks Tweakie, I'm trying all avenues at the moment. I've already tried cleaning and adjusting the gibs and tried winding the ball screw by hand and it all appears fine in both direction +&- Y. I assume it is mechanical rather than software but it's worth asking the question just in case.

Rob

3

General Mach Discussion / Drifting in the Y axis

« on: December 17, 2009, 05:18:20 AM »

I've had a Sieg KX3 CNC mill for about a year now and it's always had an issue with 'drifting' + in the Y axis. If I zero Y to the edge of the vice then run a program to say cut a pocket in several levels in Z I can see by the faces of the pocket that it drifts (steps on one side, smooth on the other). If I then go back to find the Y edge of the vice again I find that Y has drifted about +0.5mm. This figure will depend upon the length of program run, longer program, bigger drift. Any ideas?

Kind regards
Rob