They get warm, i'm paranoid about things that run warm

At the end of four runs of 4 minutes each, they were fairly hot but ok to hold by hand so i guess below 40c ?

I can easily flip the belt off and do air-cuts to prove it out.

A friend has just suggested it sounds like the controller (CSLabs) is having trouble counting pulses at full speed.

The other axes have the same drives/motors BUT one big difference is that they never run flat out because i have the mill tuned pretty low as far as rapids go, maybe only running 2000rpm max on X & Y drives.

I can pull the belt off the knee axis and connect that to this drive - see if it faults out, that will prove its the motor or not, if it still faults it points towards the CSLABS box i think ??

Can't really see it being the CSMIO not being able to count the pulses unless you have some astronomical pulses per rev.
On the Chiron my spindle encoder is set to 32,768 pulses per rev and I don't have an issue at 3800 rpm.

Ok, thanks Hood, thats the ENC module, i guess you have the same in the spindle drive encoder setup too?

I'm not hooked up to the ENC module yet, just the controller.

Yes, as mentioned previously I use the one encoder for both IP-A and Enc module, just jumpered across.

Ok, thanks.

I'm going to throw the 'scope on it again and watch what happens as speed increases.

Then I'll try swapping some motors.

I'm reading back through my massive build thread because this sounds very familiar from when i was first tuning my axis drives....

Right, before i go any further, i did some poking with the 'scope, my problem is i don't know if what i am seeing is an issue or not so thought it best to get this on the table first off.

four pics attached, 3 taken at the controller end of the cable, 100rpm, 1500rpm and 2800rpm

one pic taken at the drive with cable removed and the spindle just flicked by hand.

So, my questions:-

Do these show a problem?

Why is there so much 'crap' in the signal at the controller end of the cable when i am using proper encoder cable with the pairs twisted and used for each channel as required?

This interference appears at all encoder connections on the controller, I can't easily get data though as i'm on my own and holding the probes plus jogging etc is a bit dangerous.

Its not a ground loop as disconnecting the cable screen made no difference at all to the signal.

If its normal, i'll carry on with motor swapping etc but don't want to start pulling it apart for no reason

Don't look great to me but then I only have an old CRT scope and not a digital one, so maybe my signals would show up in a similar manner to yours if it were digital. Having said that when I used the PoScope I don't recall seeing bad signals like you have.

When you go to Plugin Control button and then choose the CSMIO do you see any red numbers for the Internal position counters. A friend did on one axis on his lathe, can't remember exactly what the cause was but I seem to recall it was bad encoder signals and the CSMIO was picking it up and showing the values in red which indicated errors.

Hmm, whats bothering me is the fact that merely connecting open cable caused the degraded signal - you can pull the connection from the controller and probe the open wire and the result is the same yet the drive seems to be sending good waveforms out form its connector.

I just really don't know if this a false lead or not yet but i don't like it simply because its there.

When you go to Plugin Control button and then choose the CSMIO do you see any red numbers for the Internal position counters. A friend did on one axis on his lathe, can't remember exactly what the cause was but I seem to recall it was bad encoder signals and the CSMIO was picking it up and showing the values in red which indicated errors.

Yes, always have done, sometimes get the "check encoder connections" warning at start up too.

It seems connected to the fact that my controller is powered up before the drives are - nothing i can do about that as the drives only have the one power option, not split power & control supplies.

The spindle encoder does not show up in that window though.