How to sharpen drill bits?

Hi Jim, as with most things it is an acquired skill but can be learned. Google drill bit sharpeners and you will find various devices that will work. Good luck,Mike PS don't be afraid to try some freehand. You might surprise yourself!

 

Sharpening a drill was the first thing they taught us in VoTech. It's really easy to do once you get the hang of it. The bigger the size, the easier to tell if you're doing it right. There are countless YouTube videos about it. I have a Darex Drill Sharpener ($1000) that a friend gave me 30 years ago when he moved to Germany. I've only used it once because I can do as good a job freehand in half the time. Smaller than about 1/8" is getting difficult for me to see well enough to do a great job. Fortunately those bits are cheap to buy.

 

I use a Universal Grinder Sharpener Machine to also sharpen drill bits. Somewhat overkill for regular drill bits as one could buy 1,000 of them for the price of this machine, but if you use carbide tooling, this machine is excellent for repairing and sharpening carbide tools with a diamond wheel.

Sharpening drills with this machine is extremely simple, as long as you have the right collet or chuck. Just mount the bit in the machine, setup one edge for sharpening and then rotate the bit to the next edge. Typically, drill bits are two flutes so rotating 180 degrees lines up the next edge perfectly. I find it takes about two minutes to sharpen even the most dull bits with this tool.

Here's a link to one for sale as an example:

https://www.shars.com/universal-end-mill-cutter-drill-bit-grinder-sharpener

I have a Grizzly which is now discontinued.

 

First couple of minutes in:

 

I’ve not done a lot of it, but...

Good tip in here for roughly setting angle...which winds up to be off 1° per side from what is stated in the second video, if I am thinking it correctly. 118° overall tip angle or 59° per side. The two nut method would give 120°




This will help too. The grooved rest would be ideal. He speaks more to rotating the bit while grinding. The video from Mitch shows him sweeping it up the stone. Not sure which is right.

 

Make sure the back of the angle is lower than cutting edge. It is called clearance.

 

Drill Doctor, I have the old model but this one is even easier. I have used it for many years.
https://www.amazon.com/Drill-Doctor-DD350X-350X-Sharpener/dp/B00D3NM3VU/ref=sr_1_7?gclid=Cj0KCQiAgKzwBRCjARIsABBbFuhCfG9HN4CwMoV-HjDMUa5HW3apoh4D3rmX6j7FtVWgSrFG8OW3h6saArIpEALw_wcB&hvadid=174251148445&hvdev=c&hvlocphy=9010810&hvnetw=g&hvpos=1t2&hvqmt=e&hvrand=7723543133411701763&hvtargid=aud-840076997981%3Akwd-1792658921&hydadcr=24658_9648989&keywords=drill+doctor+750x&qid=1577790574&sr=8-7

 

When a drill did get to hot, the metal softenes. Sharping that drill, when it is still hot, put it in water to cool of fast, so the metal get hard again.

Guido.

 

Drill dr.
Bought one two months ago- works!

 

Before you touch a drill to a regular bench grinder stone, go buy a diamond grinding wheel with a very high grit. The results will be far better than you can obtain with a standard wheel. As a side benefit, using a diamond wheel reduces the heat buildup on the bit and won't change the temper. I use an 800 grit and bought it for maybe $15 on eBay (Russian oddly).

 

If you are going to learn on a bench grinder. Get the largest bit you can find. You will need to measure from the end to the outer edge of the cutting tip, both tips must be the same. (exactly the same or it walks and only cuts with one side). Next you need to carefully measure the length of both cutting edges, again they have to be exact. This keeps the point in the center, kinda important.
I was taught by an outstanding engine machinist while I was learning to balance race engines. Drilling the crank counter weight was hard on drill bits. You can do this with small bits, it is just harder to do. The Drill Dr is worth every penny. No measuring, no setting the rake, and it will do split point bits.