THC lifting off sheet?

[Robin Hewitt]

Well if nobody else is willing to give it a go...

Up means Volts too low. The cutter tries to maintain a constant Ampage between hafnium bead and workpiece. If the resistance drops so do the Volts, the THC assumes it is too close and moves up.

As far as I can make out, most problems seem to result in increased resistance and the torch plummeting to it's death. So how to get a decrease?

If not a loose connection, my only suggestion is return current via the bed and you suddenly improve the connection by "welding" the workpiece to a slat.

It's a puzzle.