Broken Welder

[Dan Boy]

I was welding today, no problem and then my welder just stopped arcing, it's a tig.  When I try to weld all I get is an arcing sound from inside the case.  I took the cover off and I can see where it's arcing, not sure why or even if it is supposed to do that.  Maybe that arc is a broken circuit?  Anyone got any ideas?

Thanks Dan.

[Highpower]

A make and model number for the welder would go a long way in getting you some help I think. A schematic from the owners manual even more so.

That almost looks like a set of spark gap contacts for high frequency starts. But it looks like an inverter based machine so that doesn't make sense.   

Hopefully one of the electronics wizards will chime in.   

[Dan Boy]

Thats interesting what you say, the welder is a no name from China about 5 years old. Has a stick welder function along with the tig. It has now decided to work but not on an HF start, the tig side will only work with scratch start which just ruins my tip.

ANy ideas or do I take it to the shop?

Cheers, Dan.

[f350ca]

They sure do look like a spark gap. Learned to weld aluminum on a Miller add on box for high frequency that used them. They look adjustable and maybe even out of alignment.

[Highpower]

Dan, without knowing exactly what you have there I would caution you against fiddling with the bits inside. The spark gap contacts on my tig welder are connected to some very large capacitors that retain a tremendous amount of voltage. I was warned by a factory service technician to discharge those capacitors (safely) with a large resistor before attempting to adjust the gaps if needed. Those things can kill. IF that is what you have there. I didn't think inverter welders used spark gaps, but there is likely a 99% chance I could be wrong about that.

With not having any idea of what machine you have there, all I (we) can do is speculate as to what those parts actually are. Knowing what company made it, and what kind of specs it has certainly helps. I am assuming it is a DC only machine? And you said it does (did) have HF start capability?
Finding a schematic for the welder is pretty much crucial for most folks who aren't in the welder repair business.

Taking it to a shop would be the safest thing to do, although likely to be expensive depending on the honesty of the worker bees. It could cost more than the price of a new welder.  

[f350ca]

The human body makes a pretty good discharge resistor,

[Highpower]

OK, well then Dan - I guess you can disregard everything I posted above. Apparently the Miller tech I had talked to lied to me.  

[Dan Boy]

It was the HF points that was the problem after a clean and resetting the correct gap the welder works like new.

Thanks for the help guys.

Cheers, Dan.