Will Apse spent many years renovating older homes and also ran a small construction company.
3 Bit-Sharpening Options
- If you have a bench grinder, or plan to get one, you can sharpen bits freehand or use an inexpensive drill jig (see pictures below).
- If you want a simple, all-in-one solution that takes up little space, a Drill Doctor is ideal.
- There are some gadgets and gizmos that use a power drill to drive a grinder. These can get a reasonable result, with a little patience.
Each of these methods is fully described below.
Forcing a blunt drill bit through either metal or wood will wear out your arms and your patience. It can also damage the material that you are working on.
Sharpening With a Bench Grinder
Using a Bench Grinder
If you have a bench grinder, you can sharpen any drill bit.
You need to examine the drill bit carefully, locate the cutting surfaces, then simply set the drill at the right angle (around 60 degrees) on the grinder to bring up a good edge.
Afterwards, use a small file to clear out the grooves in the drill bit, so that wood or metal fragments can easily escape.
Some people can do this freehand, but most people will never be able to sharpen larger bits by eye alone—I'm one of them. A drill sharpening jig that holds the drill at just the right angle is the perfect solution.
If you have a bench grinder with a side wheel this will help you get a lot more use from your drill bits. It is suitable for 1/8 to 3/4 inch bits and will do a good job with wood drill bits at a very modest price.
Be aware also that you need space to the side of a bench grinder to fix the jig in place.
Effortless Sharpening With a Bench Grinder and Jig
Where It Gets Difficult
There is more to a drill bit than just the cutting edges. There are the 'lands' (see picture below). These are areas on the drill bit head that allow the cutting edges to meet the material that you are working on, just right.
For the first few times that you sharpen a drill bit, you don't need to worry about the lands. The more you sharpen though—especially if you are heavy handed—the more you need to re-establish these areas. This requires some serious skills.
If you want to try acquiring these, take a look at the video at the foot of the page.
Kinds of Drill Doctors
Drill Doctors are more expensive than jigs, but you will not need to invest in a bench grinder and they do not take up much space.
They are quick, robust, and easy to use, though you will need to replace the diamond grinding wheel from time to time. The cheapest model for wood and light metal drills is around forty five dollars.
The great feature is that the device reproduces the grinding procedures used to sharpen drill bits in the factory. At the end of the operation, the tip is the same as it was on the day that you bought it.
The DD750X model pictured above is the most popular model. It will sharpen standard twist drills and it is easy to create split points. It is suitable for 3/32-inch to 3/4-inch bit sizes.
High-speed steel, masonry, carbide, and TiN-coated bits can also be sharpened.
Once you have got the hang of the procedures for the different sized bits it shouldn't take more than a minute to save the life of a ten or fifteen dollar bit. There is a simple to follow, fifteen minute overview video available, plus a manual that explains everything in detail.
The Drill Doctor 500X and DD350X are smaller models that will work with smaller bits (see table).
|Model||Works With||Bit Size|
twist drill and split points, high-speed steel, carbide, masonry, and TiN-coated
3/32-inch to 3/4-inch
standard twist bits and split points, high-speed steel, masonry, carbide, and TiN-coated bits
wood and light metal drill bits
spade and twist drill bits
Spade bits: 1/4-Inch to 1-1/2-Inch, twist bits: 3/32-Inch to 1/2-Inch
How to Use a Drill Doctor
This is a simplified description of how to use the device, but the actual procedure is not much more complex.
- Insert the bit into the Drill Doctor holder/jig.
- Place the holder inside the machine with the white marks on the holder and machine aligned.
- Select the amount of material to be removed
- Make sure the bit sits correctly against the grinding wheel
- Run the machine for ten or fifteen seconds.
- Remove the holder, turn it upside down and reinsert. After, another ten or fifteen seconds of sharpening, the drill is ready to use.
Sharpening Spade Bits
The DD750X model, and its smaller cousins described above, will only sharpen twist drill bits. The DDSB (pictured below) can sharpen both twist and spade bits up to half an inch across.
The wheel of a conventional bench grinder is too big for putting an edge on spade bits, so this is one area, where the Drill Doctor is undisputed king.
It works with threaded bits, as well as conventional spade bits, as you can see below. It will not re-establish a threaded tip but it will sharpen a pointed tip.
I love the flexibility of this machine, and if working with wood is your thing, this is a wonderful device.
Some kind of lubricant/coolant fluid is essential for many metal working tasks. Forney 20857 Tap Magic will make any sharpening task easier and has the advantage of being biodegrade. There is no need to make special arrangements to dispose of any excess.
Inexpensive Sharpeners That Do Not Require a Bench Grinder
Prazi Drill Gadget
There are a lot of small, plastic gadgets on the market that claim to sharpen drill bits. Some will and some will not. Even the best ones will only sharpen wood drills.
The Prazi is one of the better ones and can be a useful tool for a few dollars.
I had one of these in the bottom of a tool bag for years and it saved me from serious frustration, more than once.
Some sharpeners can be driven by a power drill as seen above. They are not easy to learn to use and the grinding wheels need regular replacement, but they are fine for patient people who will only use a sharpener occasionally.
A machine to avoid is the Chicago Electric Power Tool sharpener pictured below. It is just too frustrating for most users and at thirty dollars, you will feel cheated.
Take the Craftsman Route
The video below is an example of what a real craftsman can do with a good eye and a knowledge of what is required to produce the perfect result.
Professional Sharpening Equipment
The JEI cutter resharpening machine (pictured above) is a laser-guided device with a diamond wheel to create precise, clean re-cuts.
Darex is another name to look out for. It produces machines aimed at small engineering companies and machines start at around $1500.