What is maximum thickness of sheet metal?

Upto and including 2 mm.

Max thickness of sheet metal. Personally, I have worked with 4 inch material on a rare occasion, however I work with 1mm (approx. 0.04 in) up to 50.8mm (approx. 2 in ) quite often. The question is somewhat vague, but if you have enough money, you could have a sheet of metal just about as thick as you want.