18 ga. steel for cutting out patch panels for my rusty old cars. Single cut I would think.
For cutting patch panels you may be better off with a double-cut/strip-cut/slitting type shear. The Slitting shears have two fixed cutters with a single moving cutter placed betwwen them. When they cut they remove a strip of material. You can also use the slitting shears to remove a thin strip of material from the edge of a piece of metal using only one of the fixed cutters and the moving cutter. If you need to cut a piece of material from the center of a panel, you drill a hole about 5/8" to 3/4" inch in the center to start the cut. The only main drawback is that because the slitting shears remove a strip of material he removed metal winds up as scrap. Draco has some videos showing the shears in use, they manufacture a number of different models some of which cut a smaller radius, or are better designed for folded edges.
First the shear for 'profiled" steel.
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And the Trumpf video on their slitting shears.
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