Kevin was TIG welding with his beloved Longevity TIGWeld 200EX when he started blowing holes in his work. He’s using a torch that has the rotary wheel control right in the torch handle that adjusts the amperage at the machine. When you’re in 4T mode, that lets you have your on / off as well as your amperage control right on the welding torch handle all the way from zero to whatever is set as max on the machine itself.

The welder was set at 120 amps, and Kevin was welding at about 90 amps, and all of a sudden he’s blowing holes in everything. He looks over at the machine to see the display is showing that the machine is running at 200 amps. No matter what he does on the torch controls, it doesn’t change on the machine’s display. So he goes to the welder and adjusts the amperage there, turning it back down to 100 amps, and watches it climb back to 200 amps again.

So he pops the torch handle control out of the handle, and swaps it with the same control from another torch. Now the EX TIG welder works correctly, so he knew he had isolated the problem to the torch handle control. He sprays the part with some electrical contact cleaner, which he got at Radio Shack, spraying it around the knob itself, then worked the knob back and forth to get the cleaner inside. Then he sprays out the control and drys it with some air, and puts it back into the torch.

Lo and behold, that fixes the problem. Kevin speculates that the combination of the dust and dirt in his art studio and the sweat coming off his gloves may have gotten some grit into the controls and shorted it out.

So if your machine goes to max amps, and you have no control at the machine or at the torch and you don’t have another switch to test it, you could also disconnect the welding torch controls and attach the pedal, and see how that works. Again, you are eliminating different options to see where the problem might be.

In this case, the problem was in the torch control.