When a professional drill that perfect hole, it always looks super easy. Then you give it try and snap! The bit is broken.
Broken drill bits are probably the most common complaint among DIYers. We’ve yet to see a single drill bit where no one hasn’t complained the same. This leads you to wonder why do exactly drill bits break and how to keep small drill bits from breaking?
In this small write-up, we’ll address both of these issues together and offer you some great suggestions that you can undertake to avoid breaking drill bits. So let’s start!
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Why do drill bits break?
Common sense says a drill bit has to be stronger and tougher than the things it is drilling. And in reality, it is exactly like that.
However, when you are drilling through a surface, be it wood, cement, tiles, marble, or even metal, there are several reasons why a drill bit might break. If we understand the possible reasons why drill bits break, we can be careful about them and prevent their breaking.
There are many reasons why they break. Let’s look into them in brief:
Using the wrong drill
The first major mistake anyone can do before drilling is picking the wrong bit for the surface. It doesn’t matter what other measures you’ve taken, you can even do everything else mentioned in this article perfectly, and still, your bit will break if you didn’t pick the correct one.
Having the correct bit type for a particular surface will make your task a breeze. This is the absolute basis for any drilling job.
You should never compromise on quality over price. Always remember that quality work will never be accomplished with cheap tools.
That’s why enough buying knowledge about quality drill bits is necessary before you visit the market. A bit may have a manufacturing defect that will lead to its breaking.
Cheaper bits are made with poor quality steel and they are also poorly sharpened. Make sure to keep an eye out for them before buying.
Speaking about poorly sharpened drills. It may so happen that after some use the drill bit has worn out and has become dull. So you need to make sure that your drill bit is sharp enough before drilling.
The point or the outer corners of the bit may become dull and maintenance will become necessary.
Sharpening those metal bits might take off the protective coating which is, however, another problem.
Incorrect angle or pressure
Drill bits usually break in the hands of novice drillers who can’t always hold the machine securely at the right angle. You need to embrace the drill bits with better clamping to prevent breaking them.
Besides, if you put excessive feed pressure on the drill the bit will break. There might be chippings you’re unaware of and your excessive pressure isn’t making things any better.
Clogged chips while drilling might cause the drill bits to break. In that case, you need to start withdrawing the drill at regular intervals. This will clear the chips away.
Besides, using polished and more generous flutes along with a faster helix angle also reduces friction that in turn reduces drill bit breakings.
Length of the drill bit
Longer twist drills pose a higher risk of breaking. When the flute and body length is too long the hole registration accuracy diminishes. So if you don’t need to drill something too thick, there is no reason to pick a long drill.
Drill not clamped
Sometimes the workpiece and the drill might not be properly clamped. And when you start drilling, the additional movements cause breakage of the bit. It is therefore necessary to fasten the workpiece well and clamp the drill firmly.
Poor strength of the drilling strength
If the drill bit isn’t thick enough and lacks strength, any large deflection could break its flute. So the thickness has to be changed for increasing the strength.
Professionals start the drill cautiously with the moderate speed at the beginning. They take care of the condition before increasing the speed.
Generally smaller bits are used at higher RPM compared to larger ones. If you happen to use a larger bit, a higher speed can result in binding and breaking.
Read More: how to keep drill bits from rusting
Take care about the end of the hole
Reducing the force and pressure while you’re at the end of the hole while drilling is important. When drillers forget this they end up with broken bits due to binding.
How to prevent the drill bit from breaking
We’ve mentioned the ten major reasons why drill bits break. Careful readers will understand from those causes how to maintain and move with the drilling process. However, mentioning the necessary tips directly about preventing drill bit breakage can help out too.
1. Choose the right bit
Check and cross-check your drill bit before working with it. Consider the type of surface you’re trying to drill through and the purpose. The package usually gives enough information and restrictions regarding these.
2. Keep it sharp
Sharp and shiny bits make the project easy. Use a bench grinder to keep the bits sharp always.
Create a pilot hole first
Before drilling any hard surface, establishing a precise center point becomes necessary so that you don’t try to change the drilling course in the middle of the work. This puts undue pressure on the bits and might even chip the flute.
3. Start slow
After making the pilot hole place the drill at the exact center and start drilling slowly in the beginning. Increase the speed steadily so as not to overwhelm the bit with too much pressure all at once. Read our latest article: self-centering drill bit reviews.
4. Don’t force
Never force the drill into the surface to make the hole. You’ll know you are forcing it when you hear the machine groaning or slowing down. When you put too much pressure the bit gets dull. This makes you force more the next time and it continues until the bit breaks.
5. Pull, clean, and repeat
While drilling wood or brick wall you need to keep the chips and flakes out of the flute. Pull out the bit after every inch of drilling and blow it off.
Apply stop and cool technique while drilling too many things. Know that the hotter the drill bit gets the faster it dulls. You can keep a container of cold water and dip the drill into it every now and then. This will also clean the bit from much debris.
Knowing how to keep small drill bits from breaking and applying the tips will help you keep them working longer and prevent breaking. With proper care and techniques, you can drill easily without harming your drill bits.