Moonlite Stepper Motor Slip Clutch

[pmlogg]

With a view to a semi-DIY motorisation of a Moonlite CS focuser can anyone tell me how the slip clutch mechanism they use in their new model motor units works? Images of the system just show what is outside of the motor box; a small knurled ring that can be tightened and loosed against another ring to engage/disengage or adjust slip.  The fitting instructions show both rings attached to the motor end rather than one being on the OTA focuser shaft.   If anyone has images of what is inside of the motor box, or detail of the cutch mechanism that would be really interesting - I've drawn a blank looking online.

A few years ago I added a Huco miniature clutch to a Lakeside motorised system but it wasn’t cheap and adjustment is a bit fiddly so if Moonlite’s slip clutch is simpler/cheaper I might try to emulate it.