How to unscrew a bolt with stripped edges: proven methods, step by step instructions

Table of contents:

How to unscrew a bolt with stripped edges: proven methods, step by step instructions
How to unscrew a bolt with stripped edges: proven methods, step by step instructions

Many home craftsmen often encounter damaged fasteners during repairs. Judging by the reviews, such bolt deformations in vehicles and in everyday life are a fairly common problem. This explains why many beginners are wondering how to remove a stripped bolt. There are several ways to deal with this task. Having the right tool, you, according to experts, will be able to unwind almost any hardware and remove the fastening fragments, even with a torn off head or a broken stud. You will learn how to unscrew a broken bolt from this article.

how to unscrew a bolt with torn edges

What is the cause of the breakdown?

So that you do not have a question about how to unscrew a broken bolt, it is better to prevent breakage of the fastening material. This means that doingits dismantling is necessary without significant physical effort. If you applied force, and the mount remained motionless, you should not continue. Otherwise, you will damage the hardware. What to do if the bolt does not lend itself? Consider different ways.

First way

For those who do not know how to unscrew the bolt, it can be recommended to remove rust and other impurities from it first. You need to clean the threaded part, which in most cases protrudes above the fastened parts. A wire brush is ideal for this purpose.

Second way

Before unscrewing the bolt, experienced craftsmen recommend tapping its head with a hammer. To break the integrity of the oxides, it is advisable to hit the fasteners strongly. The formation of small dents is not scary. It will be worse if the bolt itself is bent. This procedure is acceptable only at the beginning of work. When the bolt is torn from its place, it is no longer advisable to knock on it. The fact is that there is a risk of damaging its thread.

By heating

Those who are interested in how to unscrew the bolt, so as not to violate its integrity, can be recommended to expose the fastener to strong heat. The essence of this method is that under the influence of high temperature, the destruction and burnout of rust occurs. As a result, less effort is required to unscrew the bolt. For this purpose, craftsmen use a blowtorch, a gas burner or an acetylene torch. Since you will have to deal with open flames, make sureso as not to spoil the objects around. After heating, the bolt needs to be given some time to cool down.

how to remove a broken bolt

Through the application of a special fluid

How to unscrew a bolt without a hammer and a blowtorch? Experienced craftsmen will advise you to get kerosene, brake fluid or a special WD-40 compound. Having penetrated into all the cracks, the product will lubricate the thread and destroy the rust. Of course, for the effect to be positive, after processing you will have to wait some more time. In most cases, it takes about an hour, less often - 10 hours.

how to remove a broken bolt

If the mount does not give in, and you still apply force, then most likely it will break. In the future, it will take you much more time and effort to dismantle such a bolt. What to do if the fastener is still broken? How to unscrew the broken bolt in this case? There are several ways to do this.

With a chisel

Before unscrewing a bolt with stripped edges, you need to take into account parameters such as access to fasteners, their dimensions and location. This will allow you to choose the right tool for you. For example, large bolts that are easy to get to are best removed with a hammer and chisel. The latter should be placed to the bolt head so that the cutting edge is applied tangentially. Hit with a hammer should be sharp. Judging by the numerousreviews, this method is quite simple, but very effective. It is often used as a last resort.

Dismantling with key

If you have free access to fasteners, you can manage with a universal adjustable wrench. The design of this tool will allow you to clamp even round bolt heads. It may be that the thread broke in a very small bolt. It is removed by means of a small permutable key of the "cobra" type. In this tool, the working surface is equipped with sharp notches, through which dismantling is carried out. The main thing is that the key is new. The fact is that in a worn tool, these notches can be “licked off”, as a result of which their adhesion to the fastener will not fully occur, and the key will simply slip off. If the edges of the bolt are slightly damaged, then you can cope with the task by using a spanner wrench. The profile of this tool has 12 faces (there is a hexagon inside the head, not an asterisk). To wrap a fastener, you need to pick up a head that is one size smaller than the bolt. This head will be located in place of the torn edges. It is enough to press it onto the bolt, and then twist it as usual.

how to remove a stripped head bolt


If the fastening thread is damaged, the bolt should first be lifted with a screwdriver or other similar tool. The main thing is that it sticks out without problemsunder the head Next, you need to press hard on the screwdriver so that the bolt comes out of the part as much as possible. If it rests, start rotating it in the usual way. Well, if you are dealing with a through threaded connection. In this case, push the fastener from the reverse side with something.

By trimming

To remove the bolt you will need a hacksaw. With its help, you first need to make a cut in the head of the fastener, into which a flat screwdriver will then be inserted.

how to remove a broken bolt

It is desirable that the cut is not very deep. It is best to go deeper with a hacksaw blade by 75% of the height of the entire head. Thus, it will be divided into two halves. If the cut is larger, then one of the halves may break off.

Maybe your screwdriver will slip. This deficiency is corrected by means of a special glue based on cyanocryl. This tool is designed for fast and high-quality bonding of metal surfaces. First, degrease the mount and screwdriver. Then apply the product to the body of the fastener and firmly press the screwdriver against it. At this stage, it is important to maintain alignment. To make the glue set faster, additionally sprinkle the junction with soda. When the mixture is completely solid, start twisting.

Also, in addition to a hacksaw, some home craftsmen use needle files or an angle grinder withcutting disc. With this tool, you can process not only damaged fasteners, but also a key that can be used to unscrew a broken bolt. For example, masters restore faces to the desired size. If you are the owner of an open-end wrench, then you do not need to make a hexagon out of it. You can limit yourself to sawing two parallel edges in it.

Pro tool

According to experts, the above methods are quite effective if the broken fastener protrudes slightly from the plane of the part. What to do when the head of the bolt is torn off and the bolt itself is hidden?

unscrew the hub bolt

It is best to get a special professional tool, namely an extractor. The device is a metal cylindrical rod. One of its ends is equipped with a conical thread with an opposite thread, the other is equipped with a shank with a square section. Judging by the numerous reviews, almost every motorist has this tool. The fact is that often in vehicles the bolts that fasten the wheels to the hubs break. You can unscrew the bolt as follows. First of all, the fastener body must be equipped with a special hole for the extractor. It is desirable that the diameter of the hole be 0.2-0.3 cm smaller than the thread. Further, with not strong blows, an extractor is placed on the bolt body. Now the device can be rotated by the shank, unscrewing the remains of the fastener from the part.

About removing a broken bolt with a tap

An alternative to the extractor will be a left-handed tap. As in the previous case, you will have to make a hole in the body of the bolt. What exactly you need the diameter, you determine, guided by a special table for threading. At this stage, make sure that the threaded connection of the bolt remains intact.

Make a hole

Next, in the finished hole, cut a new thread with a tap. As a result, the remains of the bolt are removed. Judging by the reviews, it is not always possible to produce accurate drilling. If you deviate a little and therefore damage the threads of the mount, simply ream the hole more and cut with a larger diameter.

What else can be done?

In addition to the above methods, you can use welding to remove a broken bolt. It is enough to weld a nut of the required diameter to the body, and then turn it with an ordinary wrench.

Popular topic