Another plasma component...

rodw wrote:
That was exactly my experience yesterday. Sometimes Plasmac did not look at the ArcOK signal glowing on the screen and it kept burning a big hole on a pierce. Other times, my machine did not give it an ArcOK so time for some maintenance and review of cut settings I think.

I had the same experience with my CandCNC controller, Expect it was the probe sensing signal that was being ignored, Do you think that there might be something within linuxCNC causing that problem?

rodw wrote:

Dee436 wrote: I am now able to cut with the latest version of PlasmaC, but am not getting the same quality of cut I was with my previous version.

That was exactly my experience yesterday. Sometimes Plasmac did not look at the ArcOK signal glowing on the screen and it kept burning a big hole on a pierce. Other times, my machine did not give it an ArcOK so time for some maintenance and review of cut settings I think.

Did it stay at Pierce Height the entire time or did it move to Cut Height and stay stationary for a time.
If that happens again can you use HalShow to check that plasmac.pierce-delay reflects the value of the Pierce Delay for the selected material.
Also make sure Puddle Jump Delay is zero
Pierce delay and Puddle Jump Delay are the only things that can prevent moving on after an Arc OK.

thefabricator03 wrote:
I had the same experience with my CandCNC controller, Expect it was the probe sensing signal that was being ignored, Do you think that there might be something within linuxCNC causing that problem?

I'm not exactly sure. The lack of arc OK might be height related. Changed some consumables yesterday morning and got perfect cutting on large parts (10/sheet x 2 sheets 2mm) yesterday morning and then upgraded and had some issues with small parts. This morning I flushed all the air system as its similar to when I had water issues pre-refrigerated drier. I've added a pre-cooler as well so the air seemed as dry as. From observation, it seems to be too high at the start and volts are then too high. Turned off the auto sampling and dropped the voltage by 15 volts and that got it back in the ball park after the THC delay. I could see the torch jump down to height but it was not pretty leading up to that.

I'm told I've been granted some quality plasma time on Sunday so will check all the heights with the torch disabled and try a bit of tuning. I've never played with any of the pid settings and a long time ago in halscope, it seemed to be tracking the setpoint OK but was too high.

phillc54 wrote:

rodw wrote:

Dee436 wrote: I am now able to cut with the latest version of PlasmaC, but am not getting the same quality of cut I was with my previous version.

That was exactly my experience yesterday. Sometimes Plasmac did not look at the ArcOK signal glowing on the screen and it kept burning a big hole on a pierce. Other times, my machine did not give it an ArcOK so time for some maintenance and review of cut settings I think.

Did it stay at Pierce Height the entire time or did it move to Cut Height and stay stationary for a time.
If that happens again can you use HalShow to check that plasmac.pierce-delay reflects the value of the Pierce Delay for the selected material.
Also make sure Puddle Jump Delay is zero
Pierce delay and Puddle Jump Delay are the only things that can prevent moving on after an Arc OK.

I kinda covered most of this in my last post. Puddle jump settings are both 0 but now I see there is an ohmic offset so I might play with that to get closer onto correct height.

Does Plasmac probe up again until the ohmic circuit breaks again to set surface height? I assumed it would do.

Does Plasmac probe up again until the ohmic circuit breaks again to set surface height? I assumed it would do.

Yes, it probes down at Probe Speed then after sensing the material it moves up at 0.001mm (0.00004") per period until contact is lost.

The debounce delay in the connections.hal will have a minor impact on height, around 0.001mm (0.00004") increase per unit.

but now I see there is an ohmic offset so I might play with that to get closer onto correct height

You may haven an issue with that as I made the assumption that if someone was using a separate probe next to the torch then it would be below the torch so I restricted to values here to negative numbers. If you need positive numbers then you can change line 21 in plasmac_config.py from: to: I can change it permanently if required.