I suppose this has been done many times in the past, but I finally tried it and it works well. I needed patches for my 12 bore rifle, so I used an old 2 1/4 inch hole saw, spun it in a drill motor, and ground the teeth off on a bench grinder. Then ground a bevel on it, and finished up sharpening it with a stone. I had a yard of pillow ticking material I folded up so it was the size of four of the patches and about 2 inches thick. Running my cutter in the drill press and using a chunk of delrin as a backer, I cut through the whole stack in one shot. So four plunges and I now have a huge number of patches for my rifle. This works well for cleaning patches also of course, if you can get free t shirts or similar. Just don't use the drill bit in the middle of the hole saw!