re: Stupid question of the week

Honestly, I’m going on what I was taught years ago. From what I understand, the design of router collets and drill chucks rely in part on pressure created by the taper at their base. By raising the bit up, maximum pressure is exerted on the entire bit shaft. For drill bits this keeps the bit from twisting, and for router bits this keeps the bit from slipping. From an experience standpoint, I’ve seen bits slip when an overly aggressive cut is taken if the bit isn’t seated properly.