PMC 1125 pilot arc issue & Intro

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At the request of NotaVegetarian, I am moving this post, looks like it could be posted here instead of the introduction forum:Good day to you all!I'm a designer/maker (architect & general contractor) but pretty much build all my own stuff. lots of different stuff, a pool table, a couple houses, furniture, additions, cnc machines . . . it's been a fun ride . . . (www.calvinodesign.com)I started welding in 1995 with a harbor freight flux cored machine, then graduated in about a year & a half to a Millermatic 250.So, this may not be the correct location for this thread, but here's the issue I'm having:I built a cnc plasma/router table back in 2008 & set it up with an ESAB PCM 1125 that I picked up for $1K (maybe overpaid because I come to realize that I don't think the pilot arc was ever working on the machine). Anyhow, I've been cutting with it since about 2010 or so & just make sure I get the retract with the cnc tight enough to the cutting sheet/plate that it strikes the initial arc & it's been cutting fairly well all of these years. It goes through tips & nozzles very fast above 3/16" plate, but I find that 3/16" is sort of the sweet spot for it. So, I have another project coming in with some thicker plates & so I thought I'd take a look at the pilot arc issue once again & see if I can make any progress with it.Looks like Trippleback had this same issue back in 2007.I've been through all of the troubleshooting steps in my manual and as posted in this short thread: https://weldingweb.com/vbb/threads/5...1125+pilot+arc by weldinON Looks like there was no resolution to the issue.basically:1. Fuse is fine (continuity between ends)2. Heat shield is tight (see jumper test below)3. HF is working, gapped at 0.040, (see jumper test below)4. 275VDC between work & torch terminals.Here's the rub & the jumper test:Pete's Tools on Youtube (he's out of New Zealand)  did a jumper mod that produces a pilot arc where he uses a small jumper wire between the torch nozzle & the work lead. (basically the same as the pilot arc circuit does, except that it is a direct wire between the two. The circuit is much more complex in the machine for the pilot arc.

So, I ran a jumper between the work lead connection at PCB4

to the pilot arc connector where the torch connections are made here:

detail:

& the pilot arc works fine. You can see the HF arc for a split second at the HF gap as the pilot arc fires, then the main arc starts fine & it's off & cutting!Here's the question: I have it jumpered at the torch head at the moment:

& it works fine, but I'm not sure if there may be any long-term side-effects that may screw up some circuits in the machine maybe? or maybe they're already fried at least the pilot arc circuit seems to be. Anyone have any thoughts?I was thinking that a more permanent jumper in the machine between pilot arc connection and the work lead at PCB4 would keep the connection better & would be concealed inside the housing, I'm just not sure what may happen long-term with it. Any further/more in depth insight would be greatly appreciated.Cheers!Last edited by McArch; 16 Hours Ago at 11:03 AM.Reason: wrong forum moved to Machines - Tools and Cutting Methods