Faceting/Linearization leading to poor surface finish

A side observation.

The smaller the radius, the less apparent it seems to be.

First picture in original post was a 2.375” circle

Last two picture I posted were a small segment of what is actually a 12” circle.

This same part also has 1/2” rads on the contour, the the lines are significantly less apparent on those. Pics attached. In the one picture you can see the transition from the 12” arc to the small 1/2” arc, and the lines calm down drastically.

Some further experimentation. 

it appears to also show up on angled paths. Not just circles. Basically any time both servos have to work in tandem to produce a line or arc this rippling is showing up.

more pictures:

Use "hal scope" to trace
Joint.n.motor-position
And
Joint.n.motor-fb
For both axis/joints, but beware that i might have the names wrong.
Edit
Also if you have a scope or a decent DVM it would be usefull to monitor the drive voltage while both axis are i use.
All this is supposing you already checked for mechanical issues.
If this is a Tormach, mechanics is the first thing to check, from what i could gather from the net

I'm curious about the step/dir resolution of the Cleapath
servos used. ISTR the cheapest ones only have
800 steps/turn resolution which would give ~1/4 mill
steps with a 5mm pitch ballscrew.

Here’s the X motor (pic)

im not sure how to access the background stuff like HAL in pathpilot. 

The -ELS suffix indicates the hi-res encoder (6400cpr) and shaft seal options.  So I don't think the issue is caused by encoder native resolution being too coarse.

OP - if you can get a windows computer you can D/L Teknic's free tuning software.  Be a good idea to check - not necessarily change - the settings on the servo.  That may help while chasing down this issue... specificaly the Input Resolution.  That setting, coupled with the ballscrew pitch should identify the mechanical capability and minimum resolution of the 1100MX.

This info isn't going to fix anything on its own, but may help while running down other possibilities.