Hi Karl,
I know you are planning a V4 TQ at some point.
I was hoping I would be able to mod your designs myself, but Fusion is proving way beyond my learning curve for now.
I was hoping to extent the TQ stem down below the body and add an toothed/geared arc that couples with the motor.
(I only started 3d printing at christmas when my wife gave me a sidewinder x1.
Its going really well for last 5 days, only one bad print so far because the bed was not leveled. I've printed a dozen parts so far.)
Anyways,
regarding motorised TQ, I came across these a few years ago when I last attempted to build a TQ.
They are friction based clutch. I successfully prototyped with a direct drive motor via metal gears with the clutch.
I used Pololu Metal Gear motors and a Pololu controller plus these clutches:
Just thought you might be interested in them when designing v4 TQ!