one rougher one finisher.
rougher needs to run under 1000 rpms as well as finisher, feed as fast as you can with out breaking it. maybe around 2ipm? and lots of coolant. no coolant breaks tools on hard metal. I always go slow rpms on harden steel usually have of what is recomended. DOnt care how long it takes just want good parts with out tool breakage.
They do have diamond tools, I havent tried them yet, going to soon.