Rotary weirdness - defies understanding

[Stewey (Ian Stewart-Koster)]

Yes, it’s here:

4-wheel rotary finally fixed, calibrated and working with RD 6445-S older

Hopefully I’ll remember all I need, and this will be a better place to leave information than tacked on the end of a previous problem thread. I bought a 6445-S controller from Cloudray, after being told it could control a rotary U axis without needing Y to be unplugged. I believe the 6445-S was a 6445-G that had maybe been upgraded, because later I could not flash the firmware up into the 35.01, but after much upgrading and downgrading firmware (because certain versions only rotate U, and cert…