Okay, this is progressing slower than I'd like (having to work from home and it's planting season down the allotments with the wife), but today I managed to get the spindle under UCCNC control... of sorts.

There's a few scaling issues that I have to resolve, but that I think is pretty straight-forward (I hope). I think I need to resolve the servo drive to a normalised rpm, and use UCCNC to provide Pulley scaling to give a spindle speed. But, trying to get the servo spinning at the rated 3000rpm (spindle 2000rpm), with a 3000 line encoder (3000 ppr?) UCCNC maxes out at 1980 rpm (out of 3000), with a kernel frequency of 100kHz (default). That sort of makes sense to me - 100kHz kernel = 100,000 / 3000 * 60 (sec-to-min) = 2000 rpm @ servo.

I can increase the kernel frequency, but that feels like a sledgehammer solution (and I'm not keen on increasing the pulse frequency for all the problems that can come with that... but it is an option).

The other figure that influences the pulse rate to attain the RPM is the resolution of the servo encoder. Now, given that I'm only using this for a spindle I'm pretty sure that I don't need the resolution that this offers. Is there a feature with servos that allows the resolution to be reduced (i.e. fewer pulses to get a single revolution)??

The manual talks of "positional regulator gain", but I think that's a dabble-too-far, and there's reference to "electronic gearing" with some esoteric terms such as "pulse electron gear ratio of molecule 1", as well as a more understandable "demoninator of a pulsed electronic gear ratio".

Given that I'm using pulse/dir signalling, is this electronic gearing a route to reducing the resolution of the stepper, and allowing me to present fewer pulses per revolution, and therefore increase the achievable RPM without fiddling with UCCNC kernel frequency?

Or am I barking up the wrong tree?, is there another route here? Sorry, shed-time is limited at the moment and I'm trying not to jump into too many rabbit holes.