I was given an older Hypertherm Max20 plasma cutter that doesn't arc. I haven't had a chance to really look at it yet. Was wondering if there is something that regularly goes bad on these machines.Craftsman 230/140 AC/DC Miller HF-251D-1Millermatic 130 Linclon 40 amp plasma cutterHypertherm Max 20 O/A cutting and welding stuff5HP Ingersoll air compressor