Plasmac migration problems

The hysteresis is about 1.2mm...China's cheapest...

Reducing the initial probe speed makes a small difference, but the buzz will drive me nuts! If that second probe speed is hard-coded (there isn't a G38 hidden somewhere?) then I'll try to change the microstepping on that drive to work around the resonance.

It is hard coded, it is one step per servo period which equates to 0.001.mm (0.000039")
In most cases that will be 1mm/sec (0.039"/sec)

Thanks - I get the impression the hysteresis may be a bit rate dependent. I was at 200 steps/mm with 4x micro-stepping. Doubling up the microstepping seems to have quietened it down, but I guess also slowed it down.

I corrected the scaling, but I thought you were saying that final probe speed was in raw increments/sec.

I've re-parsed your words and I think you're saying it's 0.001mm/servo period, so not dependent on scaling.

Looks like I need to rethink the float switch anyway! When the torch fires it throws the float switch too. It's so close to doing something useful...

I think it was going through the air, but for what it's worth all of my signal shields go to star ground in the cabinet. I played a bit with moving the sensor in the air and seeing it trip, and it seemed like it's just a line-of-sight proximity effect. See my bodge and first cut...I did not expect this quality on my first go, I'm blown away. Thanks for all the help so far.



Edit to add, that's a 30mm hole in 5mm steel.

I seem to remember Tom asking about this slow probe up earlier and as usual I got sidetracked and totally forgot about it.
I am working on adding a pin so that a user can change the speed of the final probe up using a setp command in a HAL file.
It seems to work ok after some quick testing but it won't be able to put in 2.8 before the release as it is now closed.
When 2.8 is fully released I will push this change and you will be able to upgrade then. I have limited the speed range from 1~10 which I think should be adequate. It will affect the final height so you will need to do several probe tests to dial in your ohmic and/or float offsets. I also changed the range of the offsets to be able to cover any differences. I think the only issue with using this will be the repeatability of the switches.