How to Sharpen an 82-Degree Drill Bit
- 1). Position the drill bit sharpening jig onto a bench grinder's tool rest. Clamp into position with a C-clamp.
- 2). Position the drill bit into the jig, with the edge of the bit along one of the ribs of the jig, and one of the cutting faces positioned vertically above the other. In other words, the two cutting edges should be in the 12-o'clock and 6-o'clock positions.
- 3). Push the bit forward until it barely contacts the grinding wheel (with the grinder turned off). Adjust the angle of the tool rest so that the bit's bottom cutting face is perfectly aligned with the grinding wheel. After completing the adjustment, back the bit away from the wheel.
- 4). Turn on the grinder. Keep the bit firmly against the rib of the jig, with the cutting faces at 12 o'clock and 6 o'clock, and ease the bit forward and into the grinding wheel. Grind the face for a few seconds, then flip the bit over and grind the opposite face.
- 5). Inspect the tip of the bit, to be certain that both cutting faces are ground completely, and evenly. If one face is a bit longer than the other, re-grind the shorter face until they are of equal lengths.
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