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Did you add your new pin file to the project?
 

Do the motors have tachometers? A dirty tachometer commutator might explain the behaviour

Look like more than just EMI causing lost Ethernet communications.

It actually it looks like the 7I97T card lost 5V power briefly,
since it does a full reset. I would check the 5V supply voltage,
current capability and connections.

In addition to tommylights suggestions, you might check that the contactor
contacts have arc suppressors, especially if they switch inductive loads.

Hi Guys,

I've re-controlled a Homag CNC router to use Linux CNC with MESA controls. It's was a complicated project, but for the last year it's been working well enough for me to be running commercial parts on it.

All of the motion hardware (mechanical / servos / drives) is what the Germans put in the machine 20 years ago. It uses Bosch ECODRIVE servo drives and has ball screws on x-axis and z-axis and a rack and pinion on y-axis.

The x-axis and z-axis work fine. The y-axis is "jumpy" when moving in the y+ direction. And smooth in the y- direction. I can clearly the position errors ramp up in halscope and then it appears to catch up and get back into position. With my hand on the gantry I can feel it jump / jump / jump going in the y+ and you can clearly see it in the tool marks. If I rapid at anywhere near full speed in y+ it will get wildly out of control and start slamming back and fourth and attempting to rip the whole 8,000 lb machine apart. But it rapids super smoothly in y-.

Mechanically the axis seems fine and there isn't anything like a dust collection hose that drags differently when going in a different direction. I've manually excessively lubricated the rack and pinion and it perhaps helps a little bit, but certainly doesn't solve the problem.

I recall probably spending about 10 hours attempting to tune the PID parameters and was never able to get it moving smoothly in y+. But I'm at the point now where I need to get it cutting smoother. So I am looking for any suggestions of things to try?

Thank you!

If I recall correctly I've PLL a fpga gpio at 50meg so to rid of that wizzy OSC extra part (im cheap, I know lol). If not 50M SPI then for sure it's full on 25Mhz and plenty capable kit. 

Doesn't matter, what's important to pay attention is something ain't right at 4Mhz, I suspect Lcnc won't be happy about that in fact. Perhaps the raspi is to be avoided if running on such a lazy tick?