We all know: broken bolts can be a pain to deal with. Sometimes you even have to drill one out because it is too tight and won’t come loose. In that case, you will need to find the right drill bit for the job.
In this post, our experts will help you find the best drill bit for drilling out broken bolts. This way you don’t have to spend time and money finding the perfect bit set.
What kind of drill bit do you need?
In order to drill out a bolt or screw, you will need a dedicated “extraction bit”. These kits include left-hand cobalt steel drill bits, Spiral Flutes, and screw extractors.
This is our favorite drill bit set for drilling out broken bolts:
XEWEA Screw & Bolt Extractor Set and Drill Bit Kit
- 16 left-hand cobalt drill bits
- 6 Spiral Flutes
- 13 Multi Spline screw extractors
How to drill out a broken nut or bolt
Now that you have the right drill bits to remove a broken nut or bolt it is time to actually put them to use. With the right tools stripped or broken bolts are actually easier to remove than you expect.
Here are some simple steps to remove a broken bolt.
Removing time: 10 minutes
Punch a dent in the top of the bolt
Use a pointy tool to make a small dent in the top of the bolt. This will function as a guidance hole and reduce the amount of walking of your drill bit.
Drill a pilot hole with a left-hand drill bit
Use a left-handed drill bit to make a pilot hole in the broken bolt. This will later function as a place to insert your extraction drill bit.
Use your drill in the reverse setting (drilling counter-clockwise). The hole should be no bigger than the bolt itself. Take your time while doing this because you do not want your drill bit to break.
Pro tip: If you have a variable speed drill use it at a maximum of 20RPM.
Use your extraction drill bit and remove the bolt
Extraction drill bits are also left-handed and are used to remove the most stubborn broken bolts.
Insert the extraction bit in the pilot hole and lightly tap it in till you have a snug fit. Once the extraction drill bit is in start drilling in reverse (counter-clockwise) with a very low RPM.
Repeat if necessary
If you are unable to remove the bolt with the current extraction drill bit it is time to start over again. Use your left-handed drill bit to make a slightly larger hole and repeat.
Remove metal shavings using a magnet
Before you insert a new bolt it is important to remove any metal shavings that are left in the hole. Otherwise, a new bolt will be likely to get stuck or not even go in all the way.
A great way to remove shavings is by using a magnet. Hover it over the hole and use a brush or dust spray to loosen up small metal particles.
Which drill should you use?
Good news: it does not really matter which drill you use to remove a broken bolt. That said it is important to invest in quality equipment. Find a good hammer drill in our guide: Best DEWALT hammer drills.