Not welding, cutting.

@Beowulfsfriend Why do you think that?

@Captain_Feelgood a grinder and a cutting torch, which is similar to a welder in appearance. Plus, an idiot would use paper to protect from metal chips and a blind man would use no eye shade to protect from intense light.

@Beowulfsfriend Ah.. yeah, I see. What he's doing is working with aluminum, and actually brazing it. It's kind of like soldering. Folks just say welding because the outcome is the same. He's building those fixtures you see leaning against the wall behind him there. It's a interesting method that competes with the usual Tig welding method.