Gary.....Brad point twist drill bits are ground on a dedicated tool grinder to follow a pattern. Grinding them free hand on a bench grinder is all but impossible. You can do a grind that I have used for years for drilling sheet metal that is simular though. It can be done free hand on a bench grinder by first dressing the wheel, insuring sharp, square edges on the wheel. Use the edge of the wheel and grind a "V" in each side of the bit's cutting edges at about a 45 degree angle. The resulting profile of the bit will resemble a "W", with the middle point being longer than the outside points, this will be the pilot that guides the bit. It will cut first in the center, then the outside, then the area between the center and the outside perimeter of the bit. These will make a neat, clean hole in thin sheet metal and in wood. It will take some practice to get the relief angle and leading edge just right and even on both sides, but it will work.
If your bits are good high quality bits, I'd take them to a tool sharpening service. If not, you'd be money ahead to just replace them.
Good luck with it........Chuck
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