Steel generally takes a long time and isn't much fun, in my experience. I usually start with a drill around half the size of the final hole (maybe a 5-6mm in this case) and step up from there in 1/16" or 1mm steps. I will usually disconnect the Z and just use the CNC to position the workpiece and then run the drill by hand. For steel I try to use good cobalt bits. It takes a good deal of pressure to cut well, otherwise it just rubs, work-hardens the steel, dulls the bit, and creates heat. Make sure to have a couple extra bits of each size too. I can go months without breaking a bit in aluminum but steel is a whole other game. |