THC / lost fire


I was cutting an American flag with the Gadson Snake and everything was going fine until two last interior cuts and the outer cut. After moving, the torch fired but did not lower close enough for the the cut. Any pointers on where to start with trouble shooting? I have attempted some other smaller cuts and it does the same thing, the first cut is good but after moving to the next the torch fires, but does not lower. Thanks.

Crossfire Pro
Hypertherm 45XP
with THC

where are you clamped to?
Please do not say the slats…please do not say the slats…

go to fire control and do the THC test torch test…there is a button for it…see what happens…

Have you checked the rails for the Z axis? If they are dirty the carriage may not be able to float down to the Z cutting height. I had a similar problem. After I cleaned the rails and put some light oil on the ball screw the problem went away. You will have to clean the rails and the wheels best you can. Just a thought.

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I was clamped to the drain.

I’ll check the Z axis. Thanks.

Thanks. I will re-try the torch height test.

Try it with the clamp directly on the sheet you’re cutting. You’ll get a much better connection.

Sounds good. I will do that as well.

always clamp to metal as much as possible…THC measures in milliseconds the voltage between the plate and the torch head…if your workpiece wobbles a bit on the slats you end up with mini arcing going on between the slats and workpiece…and results in not accurate voltage readings…

it might not be our full problem…but it can compound it