How to cut a rectangular hole, smaller than 1", in sheet aluminum?

[Gadgeteer]

I wonder if there might be a tendency to over engineer this project. If the aluminum is no thicker than 0.012", then this is about equal to an aluminum pie plate.

I punched the four sides of a hole in 0.012 aluminum sheet with two wood chisels, although I did not have chisels of the dimensions needed, so mine are not to scale, but close. I, then, used the produced hole as a template to mark on another piece for replication. The chisels easily cut through the sheet with plywood as a backing by leaning on the tool, and rocking it just a bit from side to side... the cut running with the grain in the wood.