Anyone doing fine contour milling with their Haas? We have a 2008 OM-2A that consistently produces a wavy surface where it should be flat or smoothly undulating. It appears that every ~0.85mm of Z travel, the Z axis is low by a few micron, so that no matter how we mill a part, we see horizontal stripes in the play of light on the surface. I put a micron gauge in the machine and found that the Z axis can take a while (seconds) to settle at certain heights -- again, roughly 0.85mm apart. I suspect this is a control issue and not a mechanical one, because there's no simple relationship to the Z screw pitch. I wonder if the problem is unique to our machine, or if others have seen the same motion/positioning artifact and found a workaround.