JerrySharrett
Senile Member
I've always used zero rake on cutting tools for brass. Positive rake leads to "grabbing" and "digging in" for me. Especially with drills.
We are not talking about a drill!! Any loose axis, hand fed, cutting tool that has the ability to grab like a drill, brass will grab it for sure. On a lathe where the tool can not grab, unless you really have a loose and light duty lathe, positive rake is the way to go.
On any material that is subject to work hardening, brass, copper, aluminum, etc, a negative rake tool will induce some work hardening. On cartridge necks this is not good. They will work harden and split soon enough as it is just by the sizing button.