Broken bolt extraction, the Team Heat & Beat way!

[Billy Golightly]

This doesn't work in all circumstances, but if its broken off flush, or even just a little bit below the surface it will. If there is some sticking out, then its an almost guarantee it'll work.


What you need:

• Flat washer with inside diameter similar to that of broken bolt diameter.
• Hex headed nut, with similar diameter to the flat washer. Preferably a flange type nut, but not requird.
• A welder (Believe it or not, I've also actually used Loctite 495 industrial glue before doing this, but it was on a very small bolt)
• Wrench/Tool that fits the above hex headed nut.

Step #1, lay the washer over top of the broken off bolt so that whats remaining of it is in the center hole of the washer.

Step #2, Do a small, but solid tack weld in the center of the washer that joins the washer and the remainder of the broken bolt together. Be VERY careful not to accidentally weld whats left of the bolt into the hole its stuck in.

I do NOT reccomend trying this with an arc welder. It can be done with MIG and TIG if your careful, and if your a bad ass mofo it can be done with oxygen and accetylene was well. The Larger the bolts, the easier this is. In my pictures you'll see below, the bolt was a 8mm. It can be done with 6's but its extremely tricky. If you've got a TIG welder, use it. And forget about using filler rod, just get a good fusion weld.

Step #3, Right, now that the washer is welded to the head you'll need to grab that hex headed nut we talked about earlier. This is a lot simpler with a flange type nut, but again, not required. Take your nut and lay directly over top of the washer so the edges are parallel. This will probably require some needle nose pliers, dont even try and hold it with your fingers, you will burn the crap out of them.

Step #4, Make a few small solid tack welds around the edge of the nut joining it and the flatwasher its sitting on top of together. Again, Be VERY careful not to accidently joint the nut, or the washer to the surface the bolt is stuck in, or the bolt hole itself. Your main object is to stack material onto whats left of the bolt only!

By this time, you should have something that looks similar to this:






You'll notice, that I don't have a full bead around the nut and the washer. You can also see that the washer, and the remainder of the bolt are only hung together on one corner, 75% of the surface area of the bolt is still left un welded! Thats just to show you how little you need, remember its better to be to little and twist it off, than it is to much and have it welded down in the hole its already broken off in!

Step #5, put your wrench on the nut you welded on, and turn the whole conglomeration, including the broken bolt right out of the hole! With any luck, by the time your done, you'll have something similar to this:





Step #6, Re-chase threads in the hole for good measure with a tap of appropriate size and pitch. Then be on your merry way!

[300rman]

this works particularly well when a bolt is broken off in aluminum (you run into this more with cars than atv's).

you cant weld the bolt to the aluminum, so its oops free.

[Daddio]

Amen. I've been using this type of method for many years. However I don't use the washer or nut. I just build up a pile on the end of the broken bolt until there is enough there to get some vice-grips on. By the time you get a big enough pile going the heat has penetrated into the broken bolt enough to loosen up the rust and the bolt comes out fairly easily.
I have also used this method to extract broken off easy-outs and drill bits. I would say that I have a 99% success rate.
It looks like you've taken it to the next level Billy.

[Mosh]

Great write up Billy.

We use that method at the shop for broken exhaust studs on car y-pipes.It works great

I have seen the studs thin as a little pretzel stick, and this works. Usually we have to heat the maifold glowing red to get those thin ones to twist out.

We also, heat the broken, stud or bolt, let it slightly cool down till isnt glowing, then we melt bees wax down the bolt threads into the piece it is broken in.
The wax actually pushes the corrosion out of the threads, and provides lubricant to back the bolt out.
I have done that with swinger bolts, and siezed engine mount bolts on aluminum cases. You can heat the steel bolt, without damaging the aluminum, and the wax will wick down the bolt length. Slight rap with a air , and they fall right out.

[jeffatc250r]

A little monkey-piss doesnt hurt either AKA pb-blaster.