Trace out a guard you like from the TOTW catalog (for example -- they are full-sized pictures), make any changes you need or want (why else make one). Cut out the 2 to 4 pieces from hot-rolled sheet or use appropriate width hot-rolled bar stock, bend them, then rivet them and weld, solder, or braze them together. For a simple Tennessee style trigger guard, that should get you close to done. The closer you cut the pieces to final shape and the nearer in width and thickness to final your stock is, the less work you have with a file. Here's one partially completed that is going to be shaped more like a brass guard that was done in the way described, out of four pieces, 2 of 1/2"x1/8" bar stock and two pieces cut out of 1/8" sheet. I have a lot of filing to do, but I was afraid I'd be short of material
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