Have you noticed that your drill machine isn’t performing as neatly as it used to? Perhaps it is even failing hard to drill a proper hole into softer materials like wood, for example.
The problem is likely not with the machine, but the drill bit. While the drill bit is made from highly durable and robust materials like High-Speed Steel (HSS), it is still vulnerable to repeated wear and tear that arises while performing its function.
However, rather than purchasing a replacement, it is better to sharpen your used drill bits to make them work as good as new.
In this step-by-step guide, we will be instructing you on how to sharpen drill bits. Transform your old, chipped, and dulled drill bit into a form that feels like it was sent brand new right out of the factory.
Stuff You Will Need
- A Belt Sander
- A Cup of Water
- 1 How to Sharpen Your Drill Bits – the 7 Steps
- 2 Related Questions
- 3 Concluding Note
How to Sharpen Your Drill Bits – the 7 Steps
Step 1: Safety First!
Always remember that when working with dangerous equipment, safety is your number one priority.
To avoid any injuries to your eyes as a result of sparks or metal bits flying as you sharpen the drill bits, wear your safety goggles while operating the machine.
DO NOT wear gloves! A certain level of dexterity will be required to properly work on the drill bits, which can be impaired while you wear gloves. However, the main reason is for safety. It can be very easy for your gloves to get caught up in the machine and cause you injury.
Step 2: Know Your Drill Bit
Before you start sharpening, it is vital to have a little understanding of the features of the drill bit, so you know what you will be working on.
The Drill Bit Anatomy
A standard drill bit has three main features – lip, land, and chisel edge.
- The ‘lip’ is the part that does the drilling. There are two of these lips on the end of the drill bit. Both of these should be symmetrical. If one of the lips is bigger than the other, it can result in uneven, non-straight drill holes.
- The ‘land’ is what follows the ‘lip’ and provides support to be while it is drilling. It should be sharpened in a way that it leaves some clearance between the part you are trying to drill and the lip. However, the clearance angle shouldn’t be so much that it weakens the support to the lip, which would cause it to wear out more quickly. Ideally, the clearance angle should be 12 degrees perpendicular to the lip.
- The ‘chisel edge’ is the line where both sides of the ‘land’ intersect. Since it plays no part in the cutting motion, it is important to create as small a chisel edge as possible.
Why Drill Bits Chip and Dull
When the ‘land’ behind the ‘lips’ is unable to provide adequate support to it while it is drilling, it causes bits of the drill to chip away during the process.
Proper land has a curved shape that provides the maximum amount of support to the lips.
As for dulling, this is a natural process the drill metal gets exposed to extreme heat from the drilling or slowly gets attacked by the elements. However, with dull bits, all you are required to do is to re-sharpen the lips or re-define the chisel edge.
Step 3: Prepare Your Drill Bit
Check your drill bit shank for any burrs (raised edges on the metal surface) and file them in.
This is vital to minimize cases of injury that could otherwise have resulted from the burrs rubbing against your skin during the sharpening process.
Step 4: Practice Proper Movement
The next important step is to practice proper hand movement with the drill bit against the machine support, so when you actually start sharpening it, there are fewer chances of mistakes occurring.
Hold the drill bit at 60 degrees to the belt sander and place the end of the landing directly against the belt.
Raise your left hand while applying pressure to the belt with the drill bit to practice cutting the ‘land.’ For shaping the ‘land,’ you simply rotate the bit counterclockwise against the belt.
By moving your left hand towards the right, you create the chisel angle. Practice this movement until the chisel angle is 45 degrees from the lip. Your right hand should remain stationary throughout the whole process.
Step 5: Start Sharpening
Turn on the belt sander and repeat the moments you previously practiced.
Repeat the steps a couple of times until the desired result is achieved, then rotate the drill bit 180 degrees and work on the other lip as previously instructed.
Since your drill bit might get extremely hot as a result of friction, have a cool cup of water on hand to dip the bit in and keep it cool throughout the process.
Working on a heated drill bit is unwise as heat weakens the integrity of the steel.
Step 6: Have Patience
It may take quite a few times to get both the lips of the drill bit to be symmetric.
Don’t get frustrated if you are unable to achieve the proper results in the first few tries as it takes practice. Frequently rotate between the sides, so you don’t end up favoring one side over the other.
When cutting, be confident, and make deliberate cuts. Trying to ‘feather’ the tip by pressing the drill bit lightly against the sander will result in uneven lips or even compromise their cutting ability entirely.
Step 7: Test the Drill Bit
With the drill bit now sharpened, it’s time to test how much its cutting performance has actually improved. If the drilling meets your expectations, congratulations on successfully sharpening your bit!
But, in case it still is difficult and grants shoddy results, take the drill bit out and examine it carefully. Make sure that you have adequate relief on the chisel and land angles and that the two lips are symmetric across the center-line of the drill bit.
Make a note of the issues and resolve them using steps 5 and 6.
Can I Use These Steps to Sharpen My Cobalt Drill Bit?
Cobalt is a much hardier substance compared to steel. This makes it easier for the drill bit to cut through materials, and usually, they last a longer while without the need for sharpening compared to their steel counterparts. However, their very toughness can make it harder to re-sharpen them at home, but it is possible.
An ordinary belt sander might not make the cut (literally) when trying to re-sharpen a cobalt drill bit. Instead, you would achieve better results with a bench grinder. Simple turn it on low-settings and repeat the steps just as how you performed on the belt sander.
When Should You Sharpen Your Drill Bits?
How often you should sharpen your drill bits heavily depends on the frequency of uses and the materials you are using it to operate on. A standard HSS drill bit may require re-sharpening after 40 or 50 holes down.
To extend the service life of a drill bit, make sure to have it properly lubricated and that the drilling should be done at a ‘slow’ speed whenever possible. Higher speeds results in high friction, and the resultant heat can make it easier for the drill bit to wear out.
How Often Should You Replace Your Drill Bits?
Drill bits are incredibly tough tools, and in the case of most owners, you may not be required to replace one at all provided that you take proper care of them and can properly sharpen them.
Since the frequency of use, the material it is composed of, and conditions of drill operation can impact how quickly a drill bit will wear out?
The best answer we can give here is that you should consider replacing your drill bits if they are still not performing well after re-sharpening or require higher than expected re-sharpening intervals.
Re-sharpening your drill bits is an easy, straightforward process and helps you save money that you would have otherwise spent on frequent replacements. We hope you found the guide to be useful. Share it with others in your circle that would find it helpful.Last updated on: