Greetings, I wielded the crowbar and bought a set of Triumph twist drills. Today I was fussing with the fence on the DP and gashed my finger on the _side_ of the drill. I'd never known twist drills could be sharp there! (Yes, it was unplugged and the yellow thingie was out of the switch.)
Shoulda worn gloves... ;^)
All but the smaller sizes of twist drills are ground with "back taper": the tip has a greater diameter than the shank to prevent binding in the hole. The edge(s) are sharp throughout the entire length of the flutes, however it is the 'other [perpendicular] end' that actually does the cutting: the lip, extending from the chisel edge to the periphery.
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