To replace an old latch in a steel door, I had to enlarge the smaller hole from the original piece to 2 1/8". I made a fastener by cutting a hole in a 3/4" piece of plywood and fastening it to the Door. I destroyed two bits of "metal/wood" and cut through thin steel. At $10 a bit I wasn't very happy. Someone needs to make a bit specifically designed for cutting steel that has an edge similar to a hacksaw blade.