Most strong and thick sheet metals will require power tools for cutting, such as an angle grinder, band saw, rotary tool, circular saw, or chop saw. I used 22 gauge cold-rolled steel sheet metal ...

This quick and dirty angle grinder circle cutter certainly fills the bill, and makes decent cuts in sheet metal to boot ... and makes a surprisingly clean cut. Check out the build and the tool ...

Affordable plasma cutters are becoming a popular step up from an angle grinder for cutting sheet metal in the home workshop, but cutting long straight lines can be laborious and less than accurate.