Here we go

My spindle is controlled by 0-10V signal (analog output)

All my drives are analogue 10-0-10 or 0-10

When you run your spindle at 10% and 80% of maximum speed, what is the current position error and maximum error?
Did you modify in any way M20 macro?

M20 is as downloaded, no changes.

IIRC the errors were relatively high, I have spent hours messing with PID values, I can get the values very low BUT it will then creep to a stop or wobble erratically.

The ID values seem very sensitive which is why i left them out, it was the best option.

I did have a thread with details, i'll see if i can track it down.

I see that you have KVff set to 0, from my experience it's role is very important.
Did you play with it (values can be like 30 but 200something isn't uncommon)?
Also, when spindle RPM is 0, is it really 0? And what's the position error?
Is the offset voltage properly set? Spindle RPM 0 and clicking the arrow does change anything?

I'll have to boot her up to get some figures.

I found any messing with values other than P was generally bad.

DAC offset was set and it is stationery when at 0 speed

I'll get some values when messing with Kvff, most likely in the morning.

Well, from what i can see it's just crap

My guess is that spindle orientation fails because it never reaches dead-band It will reach a stop but that stop can be anywhere from -200 to +200 or so in PID tuning.

No amount of messing with values has much effect, in fact its worse since i change the bearings from grease to oil lube, its very low friction and at my previous setting with P=7000 its now started oscillating instead of stopping.

Increasing P above 9000 seems to cause increasingly violent oscillation until it faults out or i hit the red button.

Maybe these servos are just garbage for a spindle?

I have the same drives and motors on my other axes and they all work faultlessly, big difference is friction damping/load.

With the spindle oscillating a gentle touch with the hand will stop it but dead-band is still off.

Its just the generic china servo from AASD - very popular due to price.

I have tried before setting the spindle as an axis the auto-tuning but it fails to get any sensible numbers.

a simple way to test wether the Motor Controller itselv is Swinging is to

-put 0V to analog Input
-enable the Controller

-now Motor should standstill

-try now to turn Motor by Hand and see who it will stop if you release the Manual torque

if it starts to swing the Controller itselv is overtuned
if it just stands still Controller tunning is ok

Hi

removed the CSMIO connector, shorted the analogue input out and enabled it manually.

The motor was creeping, I tweaked the DAC offset a few mV and got it stationery.

When nudged by hand it was fairly rigid and held its position, no oscillating.

Re-connect CSMIO and it shows a DAC offset of 0.16V spindle is stationery, but still won't stop where its told or take any tuning.