As long as you're careful and watch the arc, you can get quite close. The heat in a "clean" plasma arc is very focused. I assume you want to cut the last fraction with a zip-disc or similar? I'd think you'd want to use settings high enough to ensure a clean through-cut. That way the metal...

Otto Nobedder wrote: If it's TIG, it's more likely to be E70-S2, a Flux-free TIG wire. 7018 is a stick-rod, usually designated ER7018. Unless they want you to beat the flux off a 7018 and use it, in which case I'd run and not look back...

Tried some plasma cutting ran into some problems. At input pressure of 70 lbs, anything above this shuts the cutter down, this limits how deep we can cut. I was learning to cut mild steel plate that is 15 mm. Using 45 amps of the 50, 1 sec flow pre, 15 sec post and 65 psi airpressure, was difficult...

About my idea for making a finger tip amperage control instead of a foot pedal. I ordered four 50K slider pots from eBay at a buck a piece, (free shipping.) I only need the one for this project, but its nice to have spares. Pots for different applications have different tapers. I would guess that a...