Shop Tip #064
© Frank Ford 2004; Photo by FF
If you can afford it, buy a second set of drill bits and take a small diamond hone or fine oil stone and grind a tiny flat spot on the cutting lips. Here you can see I have a little stripe where I've made a 90 degree cutting angle by holding the stone parallel to the length of the bit. This little flat is no more than a hundredth of an inch wide but it completely eliminates the tendency of the bit to "grab" in wood or brass. You'll want to keep an unmodified set of bits for steel and aluminum. Better yet, rather than buying and modifying a new set, buy the new set and modify your old worn bits!