A lot of people never sharpen their drill bits. Of course, some people don’t know that drill bits need to be sharpen regularly. But many prefer to buy new bits rather than trying to sharpening old bits.

But sharpening is straight forward and it is not necessary to invest in expensive tools or equipment. For most sharpening tasks, a sharpening stone or a grinder is used. For drills bits, a sharpening stone is not especially useful. But a bench grinder is really good for sharpening many different bits. How to sharpen a drill bit depends on the drill bit itself, there are plenty of different types of drill bits.

An Auger bit file is, as expected, used to sharpen auger bits. A single-cut bastard mill file is the tool for sharpening spade bits and the rims of Forstner bits. A small three-square file is used for sharpening Forstner and multi-spur bits.

The cutting edges of standard twist bits should be angled at about 60 degrees. Remember to check the angle as you sharpen the bit. Otherwise you may end up with a sharp bit but which does not produce clean holes. Use a bench grinder, set the bit on the grinder’s tool rest and advance it toward the wheel. Rotate the bit clockwise to grin the lip evenly. Note that you should wipe your drill bits occasionally with oil to prevent rust.

If you don’t have a bench grinder, you can use a commercial bit sharpening jig. They are more cumbersome to use than bench grinders. But when correctly used, they will sharpen your drill bits quickly.

Sharpening Forster bits is a three-step operation, but first you need to secure the Forstner bit in a bench vise. Now you can use a file on the top edges of the rim. Then use an electric drill fitted with a rotary grinding attachment. Lastly, use a single-cut mill bastard fill to sharpen the inside faces of the cutters.

Sharpening brad-point bits is easiest done by securing the bit upright in a bench vise. Now file the inside faces of the chip lifters using a triangular needle file. A spade bit should also be secured in a bench vise. But in this case, you should use a single-cut mill bastard file to sharpen the two cutting edges.

The benchstone is still the best tool for a lot of sharpening tasks but for drill bits it is seldom the best tool. Once upon time, only natural stones were used as benchstones. But nowadays many man-made materials are used in benchstones. Benchstones are generally divided into two groups, according to the lubrication used. Oil and water are used as lubrication. In most cases, you can actually use either one of the lubrications.