How to remove a broken bolt in a deep hole | remove broken bolt in recessed hole

In this video we will see some techniques to

remove

broken

nuts and

bolt

s in a

hole

. So I have a

bolt

in this

hole

that I need to

remove

. We also have a

broken

bolt that needs to be removed. All of these are below the surface. On this cover we have a broken bolt. The danger in removing such a bolt is the fact that the surrounding material is much softer than the bolt itself. This material is clearly aluminum and the bolt is steel. This one is clearly made of aluminum and the bolt is made of steel.

So aluminum is much softer. Before attempting to remove a bolt, there are a few things you can do to make it easier. One of the first things you need to do is "unload" the bolt. I use a spring-loaded punch. I give the lock a few taps. If necessary, use a regular punch and tap gently with a rubber mallet. This may help loosen the broken bolt. Heating can also help but you have to be careful because aluminum melts easily. You can also use penetrating oil. This will most likely help. One specific tool is a drill bit for drilling hinge holes.

It contains a moving part that is pushed forward with a spring. As the drill bit goes

deep

er into the existing hole, this portion is left behind, while preventing the drill bit from hitting the material. Because of course the cable must remain intact. The drill bit fits exactly into the hinge openings and allows central drilling in the hole. I'm going to use this to make sure I drill right in the center of the broken bolt. Look here for example. You can see that this is in bad shape. Your drill will definitely slide to the side if you start drilling into it and damage the thread.

For the first bolt I'm going to change the drill bit and use a counterclockwise drill. I push this here and tighten the screw. Then I screw it back on. The part I'm using now is a little shorter than the one I removed. So I remove the spring from this and that will still center the drill bit. So if we do it like this you will see that it fits well and we will not touch the cable. Of course, you can use a normal right-handed drill in a clockwise direction, but then you will have to use a screw extractor.

So now I'm going to put the drill in the counterclockwise position. You see the left-handed drill tighten the bolt and turn it out. And you can see that the thread is completely intact. A major problem when removing a broken bolt in a

deep

hole is damaging the threads of the surrounding material. I made them myself with allen screws. I drilled a hole along the shaft line through the screws. I made an M12, an M10 and an M8. So now we screw it into the hole where the damaged bolt is located. Then we tighten this nut so that the bolt cannot come loose.

I tighten and use the left-handed bit again. The advantage of a left-handed bit is that it removes the broken bolt in the same movement. So I put some grease on it and made sure my drill turned counterclockwise. You can see that it has taken hold. So I'm going to remove this bolt and now we should see a notch to make sure we don't damage the threads of the aluminum. We continue and there is a reasonable chance we can remove the bolt. We spray a little penetrating oil and try again. The bolt still won't budge, but we're deep enough to try a puller.

Then I call an extractor. I use a small adjustable wrench. I normally use a wrench but I have one at work. By the way, things are moving. It moves a little but comes back out. These are not the best quality extractors money can buy. This is a very cheap set. Now I take a larger size. I hit it and as you can see the damaged bolt comes out. I'll show you that the cable is not damaged. I take an M10 bolt and we can screw it in easily. Here there is really no possibility of central drilling because the surface is completely uneven.

So here there is a high probability that it will slip and damage the thread. So I spray some penetrating oil on it. Now I take a square head bolt that I have drilled along the axis line. I screw them until I find the broken bolt. I'll tighten this nut and tighten it. I use a cobalt drill bit to drill the bolt because they are very hard. We must be careful not to drill too deep so as not to hit the aluminum. Then I put a little grease on it and continue drilling. I take it off and check how deep I am.

Here you can see that a hole has started and is nicely in the middle of the bolt. Now that we have a starter hole, we can continue drilling without the jig. If you are not sure you can always reuse the guide. So I put a little more grease on it and continue drilling. We now have between seven and eight millimeters of depth in the bolt. We are careful not to drill too deep and hit the aluminum. So now I'm going to try to screw the extractor on. I hit it with a hammer and follow up with the adjustable wrench.

It seems like I have control. I normally use a key, but I have one at work. As you can see, it turned out well. Now we are trying to screw in an M12 bolt to prove that the thread is not damaged. Fits perfectly. Before screwing the bolts back into the parts, treat them well with copper grease or anti-seize agent. This way you are guaranteed that the next time you want to unscrew these screws they will not be stuck and you will be able to remove them easily. So, these were some techniques that you can use to remove broken bolts in deep holes.

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