How To: Extract Broken off Bolt EVERYTIME!!!
How To Remove a Broken off Bolt! This method works GREAT!! It's best for bolts 1/4" or larger, and the shorter the better, but it sure will surprise you!!
Guys, I'm gonna try not to feed the trolls here, but if the bolt was stuck enough to break off the head of the bolt, a pair of vise grips is NOT going to work.
This technique is for VERY STUCK BOLTS!!! It's not for one that is simply broken off because you over tightened it.
You would be amazed at how much welding something will make it expand, and then shrink when it cools, check out my other video on removing a wheel bearing race.
You can keep drilling it out, and then tap it out, BUT unless you have it set up in a milling machine, there's no way you'll get exactly in the center of the bolt, therefore when you get to the larger drill bits, you will get into the threads on the piece of work.
A reverse drill bit works great... on bolts that were broken off because they were over torqued, not rusted up and frozen. Never hurts to try though.
Just welding a new nut on the stud, will do some good, it will transfer a lot of heat, but just not enough to get all the way to the bottom of the bolt.
If the bolt is broken off below the surface, you can just place a nut over the top of the hole, and weld the stud up into the nut. It's a little more complicated, but can definitely be done.
It never hurts to add penetrating oil while the bolt is hot! I just find that most of the time it just boils off.
And finally, THANKS for all the positive comments!!!