Hi David, Thanks, it is rock solid and really happy with it.

Yes it was all designed and built from scratch. It was joint project between me and friend and was a lot of work to get it finished. he had the denford one with the ratchet and pawl design but it wasn't ridged enough so we set about a more industrial option using the Hurth coupling. Most of the DIY ones we looked at had the problem of making the shaft really tight when the Bellville's were compressed to open it and needed a massive stepper to then rotate the tool plate.

Ours works differently and when the Bellville's are compressed the shaft is free to turn by hand and allowed a small nema 17 stepper to spin the plate.

There was talk of doing a small production run of them so I'm not sure if I could post up the plans yet.