Some Recent Research on Twist Drills and Drilling

The production of holes in manufactured parts is probably the most important single manufacturing operation. The twist drill, geometrically, is the most complex cutting tool in common use. Twist drills have changed little, but drill performance has improved, largely due to research in high-speed steel metallurgy and heat treatment. The author discusses how twist drills work, the life of twist drills, size of drilled holes, and normal variations in performance. (Formerly 23T5)