how about the airpressure?
Should I start at 80 pounds if I'm starting at 25 Amps?
I've cut some 1/4" B 4 also.
I use 65 psi on 1/4" all the time @ 25-34 amps depending on rust and the template.
It sounds like your electrode may be loose also. I'd like to say it's a combination of all the problems mentioned. Little water vapor, slightly loosened electrode,over amping, and too much pressure.
I've got the 60A Torch upgrade on my SC50, thus if you've got a 50A torch I don't know anything about how it behaves.
I set my 65 psi while the air is flowing with "Test Mode" on.
Hope my info helps,
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