[aerohead]

Aluminum would be great!I've never done heli-arc,but have been told the learning curve is short if you have access to TIG and shielding gas.Someone more clever than I might even come up with a weldless joinery technique(like baby-buggies and bicycle trailers use).Some grades of aluminum are heat-treated and rather stiff and un-malleable.Your friend could probably show you how to anneal it for easy forming without fracture.Enjoy that dusk mask!