Quote Originally Posted by Gary Campbell View Post
Low torque motors will produce a very uniform "scalloped" edge. This is often referred to as chatter, but if you look closely you will see that the scallops line up from top to bottom even tho a dozen or more passes have been made. The fact that they line up removes the possibility they were random, eliminating chatter. They are evidence of "detent jumping". Circles, and the changing torque requirements as the 2 axes change speeds and reverse direction are difficult to cut perfectly, and therefore used to spot the issue.
Interesting. There's an image of a pen-drawn circle or logo from the original Kickstarter version of the Shapeoko which I believe depicts what you've said.

I'm also curious if what you are describing would explain why there was one incredibly slight disconnect along the outer curves of the locking register calipers I cut on my machine:

WIN_20150914_192800.jpg

Discussed it w/ a couple of folks, but nothing obvious jumped out as the cause --- since it could only be felt, not really seen wound up taking it off when finishing. Need to revisit those and make a pair in brass on my Nomad.