Hi all,

I apologise if this has been covered elsewhere, but I don't even know if I'm using a proper terminology for the problem.
So here's the thing - I have new Wabeco mill, linear rails/ballscrews, 2kw motor, comes from factory with Nema 43 6 amp steppers, 1:2.5 ratio - German engineering and in house manufactured. I have my electronics package (Centroid Acorn, Gecko 201X drives), machine is precise, backlash is a few microns and everything is looking generally nice.
However, milling a hole makes a hole creep along x - conventional milling to the right, climb milling to the left. It happens only on X axis. Otherwise hole dimensions are good and no matter what I do (speeds/feeds/acceleration).
Everything is chatter free, end mill is new Widia 3 flute, steppers are working fine (no stalls or anything), my milling numbers are very conservative and material is Aluminum. Setup is beefy vice secured to the table at 4 points, nothing is loose.



This creeping is pretty consistent - not something erratic or occasional - as if it were programmed - except that it wasn't. Hole was produced by Centroid conversational and simulation produces a hole, not this skewed thing. Produced G code looks ok.
Other operations I tried were fine - facing, plunging and cutting slot directly with g code, etc. I don't know what else to try.

Many thanks,
Bruno