I mail them to a local carbide repair shop. They sharpen them with a cnc machine, along with my table saw blades and router bits. They clean them up real nice first, then sharpen them so sharp that you cut yourself looking at them! I'm sure there's a multitude of similar places in your area. The prices are not so bad as you might think. The cnc is probably already programmed for every drill bit, router bit, saw blade there ever was, and they get stuff done so fast. Even if you brake a tooth they fix it for a buck or two and grind it down to match all the rest of the teeth. Not that you can't do it all yourself, but you can't do it yourself ever and have results on the same planet as the cnc. I wouldn't let the guy out in the country with his little power grinder go anywhere near my blades. He gets them sharp, but all the teeth are at weird angles and they are no longer in the same plane of travel. You realize, like a planer or jointer, the teeth on a tablesaw blade should all be hitting the wood at the same height, and if a few teeth are higher than the rest, they do all the work and wear out, then the rest of the teeth have to take up the slack. A drill bit can be the same way. You need it to stay uniform on both sides or you will have one tooth/flute doing most of the cutting and you of course get wobble due to imbalance. Just sharpening the point of a drill bit isn't sharpening the bit, it's just the first step. Those norseman perform so well because they are so sharp all the way up the flutes, allowing debris to be cut up into smaller pieces that are easier for the bit to eject, and at the same time, the small pieces are small pieces, not dust. The bit shouldn't be creating dust/powder in the hole.
