Right?!? It kinda looks like the katamari prince's head, including his ear muffs and lil antenna deal. Okay maybe I've been staring at this for too long today. I extended the aluminum plate (which is now going to cost more like $70 with all the tapped holes), added the Z-axis servo and R-axis stepper, added a nub for the servo to lift, added the pressure flexure, etc. Note piece separation: the top cap is the upper bearing mount so it needs to be printed upright, while the pressure flexure should be printed flat on its back like the main Z-axis flexure. I didn't mash the two flexures together because I need to be able to insert the spindle!

All that is left on the Z-axis is the manual pressure adjustment knob, which will push down on the pressure flexure in a similar fashion to the test rig. That way, the user can adjust pressure during a cut, which seems reasonable for a test machine. During testing I observed significant cut width differences in ~60 degree turns of an M3-0.5 screw (i.e. ~80 um displacement) so directly pushing down with the servo horn won't be nearly repeatable enough with a cheap hobby servo. So lifting it is!