AC / DC Setting is backwards?

[JonS]

I have a PowerTig 185 that I've been trying to get dialed in.

I'm trying to weld 18Ga automotive sheet metal. Not even trying to use filler rod; just running the electrode across the metal to see if I can form a puddle. I have a pretty fair amount of experience with MIG welding and understand the concepts of TIG.

On the DC setting using orange tungstens, I always melt the electrode almost immediately. Gas is set to 15. Arc appears to be good. The welder is only set to 35 to 45. After a few seconds I notice I'm losing the arc and if I check the tungsten it has balled up under the cup.

If I change the setting to AC, then I notice that the electrode appears to have a louder arc, but I'm able to properly puddle the metal and the tungsten doesn't turn into a ball as I'd expect it to do on the AC setting.

This doesn't make any sense to me, but I'm wondering if anyone has an idea of what might be going on here. Is there any chance that the switch could be backwards? How would I check to find out for sure?

Jon

[SeanMurphy265]

When you say electrode are you talking about the tungsten or the filler rod? If your talking about the tungsten you may have your polarity reversed. The tig torch should be connected to the negative terminal, and your ground clamp should be connected to the positive terminal.

[JonS]

When you say electrode are you talking about the tungsten or the filler rod? If your talking about the tungsten you may have your polarity reversed. The tig torch should be connected to the negative terminal, and your ground clamp should be connected to the positive terminal.

You nailed it. I'm an idiot.

Had the ground on - and the torch on +.

I'm going to give this another run tonight and report my results.

Jon

[performance]

Should be completely different results. No need for 45 percent, and get rid of that orange/ceriated tungsten. Use red or lanthanated. Cerium won't hold the heat as well.