A friend asked to cut a boat 'name pattern' out of metal sheets. They are two thin sheets of copper with a very hard metal core. Total thickness about 1/16'' After some experimenting with different blades, without success, I asked FD Mike for suggestions. He recommended the FD-IM No. 5. I'm happy to report they worked just fine. I sandwitched the metal between two sheets of 1/8'' ply and used medium blade speed and VERY slow material feed. I've learned so much good stuff on this forum, I thought I should pass this along. --Moonie