Focusing on possible mechanical sources: A Z-axis not capable of lifting the spindle at max slew, but sized well enough to drive the spindle down, would behave in this manner.
Glenn -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jeff Epler Sent: Saturday, May 17, 2008 3:17 PM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] Z-Axis Drifting Problem On Sat, May 17, 2008 at 02:33:04PM -0500, Ray Henry wrote: > I can't see how electrical interference would cause bad counting in > one direction only but you might make certain your encoder cables are > grounded at the drive end only. I agree this sounds a bit strange, but I've seen this on two occasions. Once the encoder sensor was physically dirty, and in the other case there was electrical noise due to (iirc) bad grounding. In both these cases, the position error was consistently biased in one particular direction. You're right to suggest not dismissing electrical interference in this case. Jeff ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users