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Drill Sharpening
I have one of the drill doctors and am happy with it. I'm a retired machinist however and do a lot of drilling in metals. The thing I like about them is the split point feature. This grinds the web of the drillbit, to extend the cutting edge of the flute right into the center of the bit. This makes for easier and more accurate drilling in harder metal.
Last I saw, the price on these was aprox. $150. If you have manual dexterity they can be sharpened on a bench grinder. Start with a freshly dressed grinding wheel and the tool rest adjusted to within 1/16" from the wheel (safety item). If you must wear gloves use leather. Any kind of fabric is a no no. (safety again)
Position the bit with your R hand holding it near the cutting end and your L on the end without flutes. Without touching the wheel yet, lay the cutting end of the bit on the tool rest with the rear of the bit about 30 degrees to the left. Now rotate the bit till one of the cutting edges is horizontal. Lower the end in your left hand just a few degrees and gently bring the cutting edge in contact with the wheel, at the same time rolling the bit down with your left hand. Try to grind a little more (deeper) as you roll it down. This will produce enough clearance at the "heel" of the bit to let it drill instead of rub. After a couple of strokes, roll the bit in your fingers to bring the other cutting edge to the same position and do the same there. Try not to overheat the bit and have some cooling water to dunk it in as needed. When your finished, if you hold the bit verticlely and look at the side of each flute where you've ground, the toe (cutting edge) should be noticably higher than the heel. Then if you look straight on at the two cutting edges,(like you were going to drill your eye) they should meet fairly centered across the web and the cutting edges should be the same length and angle.
This sounds complicated, but isnt. With very little practice your hands will pick up the feel of it, and within a short time you'll be able to sharpen a bit and never forget how.
You won't be able to sharpen a drill bit with a file, they're to hard.
Good luck
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