Originally Posted by Melvin
I came across some very interesting scrap metal at my new job the other day, the material is inconel, they use the pieces as a flame diffuser for laying asphalt I believe. The best way to describe the piece is a double punched louver. For every punch in the machine, it makes a "one up, two down" pattern. I'll grab a piece for pictures tomorrow, but I think with some patience and a shaping block you could make some neat cheese grater shrouds.
Inconel is mean-tough, you'll want pieces that are very close to the final size you need. That would make a hell of a shroud though.