Know-How Notes: How to Sharpen Drill Bits The Easy Way

The easy way is often described by old-timers as the wrong way, but that isn’t always the case. Another way to put it is that there is the right tool for every job, and the same applies to sharpening drill bits. There is a right way to do it, and there is the best way to do it. Yes, you can absolutely sharpen drill bits using a bench grinder or small belt sander, but that method, while fairly simple, is not easy. You can absolutely destroy the cutting edge of your drill bit trying to figure out how to get the right angle. Why waste your precious time when there is a tool that can sharpen drill bits in less than 30 seconds each? With perfect results, every time, the Drill Doctor is your best bet.

As discussed in our recent article on drill bits, the most common bits use either a 118- or 135-degree angle. The Drill Doctor 500X is capable of handling both, with a simple adjustment. The machine can handle bits from 3/32”, on up 1/2”, up to 3/4” with an optional large bit chuck. It can also split points for self-centering. This tool is real time saver, especially when you have a bit that goes dull in the middle of project.

Sharp drill bits are safe drill bits. The act of drilling is quite literally a process in which material is ripped away from the main body. Dull bits cut slowly, require more pressure to cut, and increase heat put into the part. All of these things lead to off-center holes, ruined parts, and broken bits. Breaking a drill bit while drilling is very dangerous, often ending in a bloody mess on the bench because you impaled yourself. Sharp drill bit, just like a knife, cut the material quickly and efficiently, so that there is less trauma on the material, and less trauma on your human body.

Using a Drill Doctor is simple, we have put together a guide to using this tool to make sure your drill bits are sharp and safe. Begin by selecting your bits. Inspect the tip of each bit. If there are any chips or jagged edges, the bit needs to be sharpened. Carefully feel the edge; it should be sharp and not rounded. If one side of the bit is smaller than the other, the bit has been favoring one side; this is to be rectified by sharpening.

Next, you need to decide what angle you want on the bit. Most hobby-grade bits use a 118-degree angle, and this is the standard angle setting on the Drill Doctor. You can change the angle of the bit, you just end up sharpening it a bit more to get a complete change. See our article on drill bits for more details on the differences between the two. A 118-degree bit has a sharper point, whereas 135-degree bits are more flat at the tip. With the Drill Doctor plugged in, but turned off, place the chuck into the alignment guide with the notch on the chuck in the 118-degree mark (straight up). If you are sharpening a 135-bit, adjust the chuck one notch to the right.

Open the chuck by rotating the grip. Slide the bit into the chuck until it reaches the clamp arms. Press the button to open the clamps with one hand, and slide the bit in place with the other. Release the clamps. The clamps will align the bit to the correct position. Tighten the chuck so that it grips the bit firmly. Make sure the bit has not dropped between the gripping blades inside the chuck.

Next, select the drill angle on the Drill Doctor’s sharpening port. Loosen the knob and lift the port to match the desired angle, 118 or 135.

Turn the machine on and insert the chuck into the port. Slowly push the chuck into the machine until the chuck is seated in the port. You may hear the bit contact the spinning sharpening head.

Push the guide port up until it touches the pin at the top. You are ready to sharpen. Slowly spin the chuck clockwise, counting each half rotation. Every even number is one turn. Most bits take 20-40 spins to complete the sharpening process. Work the bit until it does not grind. You can check your progress occasionally as you go.

A properly sharpened bit will have clean chisel (cutting edge), a heel that is lower than the point (called positive relief), and the chisel angle should be at 1-1:30 when looking at the bit as shown. If the angle is at 2 o’clock, try again, only move the notch 1 to 2 places to the right. If the chisel angle is at 12:45, move one to the left. You can fine tune the angle to match your bit, which is one of the great things about the Drill Doctor.

If you not splitting the point, you are done. If you are splitting, the point, then keep the bit in the chuck and move to the next step. Splitting the tip on a bit is super easy with the Drill Doctor. After sharpening, simply insert the bit into the splitting port (on the side of the machine), and slowly press it into the running sharpening stone. Take the chuck out, rotate one half turn, and repeat. Two steps, all done. A split tip with help keep the bit centered in harder materials.

Sharpening drill bits by hand is an art form, one which while certainly useful, is hard to learn and takes a lot of time. The Drill Doctor is simple to use and well worth the money to get the job done. This author regularly puts his 13 year old son to work in the shop with a bucket of old drill bits and the Drill Doctor. It is that easy.

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