Has anybody here ever tried (probably by mistake) TIG welding Aluminum with C25 instead of Argon? If so, what did the results look like?
The reason that I am asking is that I just swapped a gas cylinder and my welds went from OK to awful looking. I am welding 6061 aluminum and the weld pool gets a big hollow space in the center and the hollow space has some light brown crud in it. The rest of the weld zone is kind of gray. The crud brushes off with a wire brush.
I suspect that the vendor filled a cylinder labeled argon with C25. As a test, I welded the same pieces of aluminum on the other side with gas from a different cylinder and it looks fine.
What really stinks on this (beside the trashed work) is that I got the cylinder back in July and I am going to be really surprised if they do anything but charge me for another cylinder.
Thanks, BobH