My Newb Plasma Table Attempted Build

I don't see a version under the config tab (screenshot attached). Ran man plasmac command and it says version .113 2020 APR 17

OK, open a terminal: Then open LinuxCNC like you normally do and that will get you fairly recent (buildbot is a few days behind at the moment).

Maybe give it a quick run to see if the behaviour is the same.

In the meantime I will go through your config and hopefully have an answer for you in your morning...

Will do, and thanks.

[strike]Something you can try is to increase the Arc OK Low to around half your expected Cut Volts.[/strike]

EDIT: Oops you are using Mode1 :blush:

Is it better to use mode 0 for arc ok?

No, that is for machines that don't have an Arc OK signal.

What was your original MAX_VELOCITY and MAX_ACCELERATION?

Uhhhh 1.5 and 60 *I think*. I changed them several times earlier yesterday trying to get it to play nice, I'll have to go back into my backup (on my other computer) and see what they were for sure.

Edit: AXIS_Z were 1.5 and 60, JOINT_3 was half that.

I can't see anything obvious in your config.

You may as well put them back seeing how slowing them down didn't change anything.

Change PID P Gain to 1 to slow down THC then you may need to do some cuts with halscope running to see if we can sort the chickens from the eggs.

You would need to scope plasmac.thc-active plasmac.arc-voltage-in plasmac.axis-z-position plasmac.led-down
Use thc-active as the trigger

Had a bunch of stuff to ship out via post this morning. I'm fixing to do the changes and see what happens. I'll report back in a bit.

I reset the PID P gain to 1 and turned on THC on a part I just cut. It did not dive at all. I don't think it attempted a move at all though. Going to cut another one and see...maybe it's too slow (needs to be dialed in?).

EDIT: This is a different part (larger outside cuts)...this time the torch went UP under THC until valid arc was lost and then paused. It's only doing this on the outside cuts. The inside cut is basically a small offset from the outside, and it did fine there. It *seems* that it's just doing this on outside cuts.