Searching for how to drill out a bolt (Broken bolt) is normal because drilling out a broken bolt is a common work for the people who are connected with construction work.
During the construction work, somehow the bolt can get broken. So, it is very important to know how to drill out a broken bolt while working for the completion of home improvement and construction work.
We will know a brief description of how to drill out a broken bolt instructed by a drilling expert.
But before that, let us know what bolt is?
Now you might be thinking that everyone knows what bolt is.
No! everyone doesn’t clearly know about the bolt. Because maximum people get confused between a bolt and a screw.
Difference between a bolt and a screw
A bolt is a type of fastener which is accompanied by a nut that helps to unite or hold two unthreaded objects together.
And a screw is a small and sharp pointed pin made out of metal that is used to stick two threaded things together.
Quick Overview
Types of bolt
Different types of bolts are available. Below, the bolts which are commonly used are given:
- Blind bolts
- Carriage bolts
- Eye bolts
- Machine bolts
- Hex bolts
- Penta-head bolts
- Anchor bolts
- Double End bolts
- Round head bolts
- T-Head bolts
- U-Head bolts
- Socket Head bolts
- Shoulder bolts
Features of bolt
The bolt contains a head and a cylindrical body accompanied by a nut. A nut is the part of the bolt which is round in shape and has internal threads to fit into the bolt.
Types of nut
I am sharing a little bit of information about the nut because the nut is the partner of a bolt.
Some common types of the nut are:
- Hex nuts
- Lock nuts
- Square nuts
- Wheel nuts
- Slotted nuts
- Flange nuts
- Coupling nuts
Reasons of a broken bolt
Now we will talk about “why the bolt gets broken?”
Isn’t it good to know the reason behind the broken bolt? If you know the reason then you can prevent the bolts from breaking.
It will save your three important things: money, energy, and time.
- Number one reason is bolt locking. While locking bolt, due to excess vibration a stress is created on the bolt causing it to break.
- Fatigue
- Corrosion
- Overstressing
- Hydrogen Embrittlement
How to prevent a bolt from breaking?
There are some ways to prevent a bolt from breaking.
- Avoid Overturning and tightening the bolt often
- Replace the old bolt with a new one every 2 two years
- If the bolts get cracked due to overstressing, then change them immediately
And Finally, your wait is over!
We are heading to the process of drilling out the broken bolt.
How to drill out a bolt: 2 methods
Drilling a bolt out isn’t a tough work. But sometimes it can be hard depending on from where you need to drill out the broken bolt.
There are two methods of drilling out a broken bolt. One method is drilling out the bolt using the extraction method and another is drilling out the bolt using the welding method.
Now let us start the process:
Drilling out the broken bolt using an extraction method
- At first, with the help of the center punch, you need to mark the center of the bolt.
If the mark is wrong, the center punch should be angled to drive the center mark over.
Warning: This can be sometimes tricky, especially if you are working in an awkward position. So be careful while making a mark with the center punch.
- Now take a center drill and attach a small bit with it for drilling into the marked center of the bolt. But there may be too much flex so you can risk breaking the bit or having it wander. So, you have to be careful while drilling into the center of the bolt using the small drill bit.
Use a cutting fluid or oil while drilling the bolt as it helps with lubrication for keeping the drill bit cool and preventing it from burning out.
- Once you are done drilling the center of the bolt, move up to the accurate size drill bit. You can select the drill bit size required for the size bolt used with the help of an indexing chart
A Left-handed drill bit can also be used. The Left-handed drill bit will rotate in the counter-clockwise direction and thus this force will help to take out the remaining stud.
Tip: Take your time while doing this process to avoid any kind of damage. If needed then apply cutting fluid or oil more.
- If you want to place a new bolt then polish the surface properly before placing the new one. Because during the removal of the broken bolt many metal fillings come out from the drill.
So, it is important to clean the metal fillings before placing a new one.
Drilling out the bolt using the welding method
- First of all, center punch the broken bolt with the help of a hammer and an extractor like the previous method.
- Now take a drill bit which is one-quarter of the diameter of the bolt and drill the center part of the bolt.
- Now attach a hex nut onto the bolt tightly
- Then weld the bolt to the nut properly. If you are new at welding then avoid welding the bolt to the nut. Take help from anyone who is professional at welding.
- Now take a wrench or vice grips and remove the bolt by holding and rotating the nut slowly.
It is better to use an air drill while drilling out a broken bolt in a tighter workspace.
Frequently Asked Questions (FAQs):
Why a center drill is used while drilling out the bolt?
Here we are using a center drill because a center drill is very rigid which allows for accuracy.
What is a left-handed drill bit?
The left-handed drill bits are the bits whose flutes rotate in the counter-clockwise direction.
From where can I buy left-handed drill bits?
You can easily buy left-handed drill bits from amazon or any local home improvement tool center.
Whole article at a glance
By now, you have learned two methods about how to drill out a bolt. Hope you will be able to drill out your broken bolt easily using any of the two methods.
But remember to use cutting fluid or oil while drilling out the bolt.
And if you are using the second method and you are a newbie at welding then avoid welding the bolt to the nut by yourself.
Make sure to take help from any professional welding guy.
And if you are professional at welding then make sure to take safety measures while welding the bolt to the nut.
So, while drilling out a bolt, follow each and every process of a particular method, tips and warnings of how to drill out a bolt carefully.
Leave a Reply