Center Spot Sheetcam Post

I am not sure at what voltage your Arc OK comes on at.

At values lower than your Arc OK if the torch doesn't fire then the Torch On light should stay lit and it should be waiting for the correct voltage or Arc OK, whichever comes first.

Did you rebuild after copying the file across?

Well, I got in a hurry and missed the instruction to rebuild. I just swapped the file and restarted LinuxCNC. I will rebuild tomorrow and try again. There are no other changes in the file other than those relating to dimpling? I’ve got some parts I need to cut tomorrow and wanted to be sure this file will be safe to use.

No, everything else stays the same.

docwelch wrote: With my 45xp set in marking/gouging mode and turned down to 10 amp as the book says, 50mS torch on time set in PlasmaC, I still have the same issue - the first torch fire works, the second does not, the third one does. I don't have the mechanized marking shield they call for but the other consumables are as called out in the manual.

Next test is Phill's experimental version posted earlier.

Steven

My thinking is that the 50 ms was not 50 ms becasue of the latency in turning the torch on. So 50 ms might only have been 10 ms or so or even 0 ms. I noticed that the 20 second delay you mentioned you needed coincided with the post flow of your machine.
I'll do my own thing for a while and report back.

I was thinking that the 50mS rather than referring to torch on time means 50mS AFTER Arc OK. This would equate to 350 in the experimental comp. But... if you need to change consumables to achieve this then there is really no benefit gained from having this 'spotting' addition to the config, it could easily be obtained from GCode.

phillc54 wrote: I was thinking that the 50mS rather than referring to torch on time means 50mS AFTER Arc OK. This would equate to 350 in the experimental comp. But... if you need to change consumables to achieve this then there is really no benefit gained from having this 'spotting' addition to the config, it could easily be obtained from GCode.

It would seem that figure would be with the arc OK, most cnc plasma machines would need the arc OK to work.

I think so too and then that brings us back to the issue that you guys with high amperage machines are going to burn a crater rather than a dimple due to the current and amount of time to get an Arc OK.

phillc54 wrote: I was thinking that the 50mS rather than referring to torch on time means 50mS AFTER Arc OK. This would equate to 350 in the experimental comp. But... if you need to change consumables to achieve this then there is really no benefit gained from having this 'spotting' addition to the config, it could easily be obtained from GCode.

I don't think so as even just waiting until arcOK blows a hole maybe 12mm deep in 16mm steel. Thats a bit more than a dimple! I'll keep experimenting but what works for me may not work for HT machines.

That was referring to Stevens 45XP set to Gouge mode, 10A and marking consumables.

Rod

I am sure that without using external hardware (as Keith does) or fast arc voltage monitoring the path to success will be different for HT and TD power supplies. My TD A-60 requires a torch fire signal at least .7s long to get the torch to fire even briefly when using the torch fire button on Plasmac (maybe some knowledgeable TD engineer can weigh in on this) . The OK to Move signal is also very slow, I typically use zero pierce delay up to 10ga steel. I believe that stopping the arc is fairly quick once the torch fire signal is removed. This is sounding like it is time for a little halscope investigation.

John