Nice job with answering the questions.
A few reply comments:
That might be true. I would try it and see. I am lucky that my cutter (Hypertherm) is more accommodating to higher pressures since it regulates what it needs.
If you are using my number system, and referring to this comment:
I was talking about the power supply in the enclosure. This should help you with that:
And as far as your ground clamp, unless you took it apart and cleaned rust off all the wire and washers and clamp, cosmetically you might have improved the looks but that is probably the extent. Again, like the pressure, make the suggested changes to at least rule out all of the possible contributing factors. As for the work lead connection inside the plasma cutter, some have found that it looked solid but as soon as they started to loosen the nut, the entire connection crumbled.
I repeat: You want to rule out anything that might be contributing to this issue.