> I am concerned with grabbing and chipping the wood around the pins. > >David Love What Ed said, and one more thing. A little trick I learned for drilling cast iron works very well here, for drilling plastics, or anything else where bits want to grab and dig in when you're slightly enlarging an existing hole. With a whetstone (diamond grit one works best for me), grind a small flat on the cutting edges of the bit, parallel to the bit's length, which would be perpendicular to the direction of the cut when the bit is rotating. It doesn't take much. Instead of the bit screwing itself into the hole and chewing everything up (or breaking), it will controllably scrape it's way into the hole at your chosen feed rate. This doesn't seem to adversely affect the accuracy of the hole size, but it does heat the bit up a tad more. Seemed like a fair trade to me. Ron N
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