Drill Bit Geometry Drill Bit Geometry ManOfSteel8357 (Materials) (OP) 20 Aug 12 16:52 Is there an equation that relates a drill bit geometry to it's axial cutting speed given material type and drill RPM? RE: Drill Bit Geometry ornerynorsk (Industrial) 21 Aug 12 09:11 You cannot exceed the helix angle of the tip edge relief in feed. Not without a lot of horsepower and a very tough drill bit material. Practical application is considerably less than this :>) It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all. RE: Drill Bit Geometry TVP (Materials) 21 Aug 12 10:49 No, there isn't a fundamental equation that relates cutting speed to drill bit geometry. It just isn't that simple.