From CoMakingSpace Wiki

High Speed Steel (Schnellarbeitsstahl) is an alloy often used for drill bits and other tools that need to be able to withstand heat.


HSS-R stands for rolled high speed steel and is the most common twist drill bit material [1].


HSS-G drill bits are cut. The drilling is supposed to be more effective and easier than with the cheaper HSS-R (rolled) drill bits.

Drillable materials: