Technical reverse-twist drill bits......

Yes. Once. I was amazed when the screw backed out on the bit.

 

I agree 100% with welding flat washer first then welding nut to washer fill inside of nut with weld then let cool before putting wrench on it, maybe a little penetrating oil. I’ve had good luck with this

 

I have mentioned this before.
Being a farmer and living out of town, I often had to improvise.
Never used an easy out, - I always drilled a small hole, got a slightly larger allen key, - tapped it in with a hammer and turned it backwards.
Never failed me, - but your results may differ…….

 

Yes, a couple of times with small diameter screws. An added feature is that the drilling is going to heat things up as well, aiding in its removal. I remember reading a Gus Wilson story where he managed to remove a broken head bolt that way, but then, Gus Wilson could do anything!

 

I prefer the “weld on a nut, with washer” method.

I couldn’t drill a straight hole in a bolt so I could use an EZout if my life depended on it.

 

His "Model Garage" was the gold standard for repair shops.

 

I always wanted to see him have his fill of Silas Barnstable's bullshit and physically throw his ass out.

 

I mess with a lot of dead antique 2 cylinder John Deere tractors. The manifold bolts ALWAYS break off in the heads on these things, so I bought a bunch of left hand bits many years ago to help remove the bolts. My advice: Use plenty of penetrating oil and patience. Getting in a hurry will just cause you to screw up a cylinder head and probably something else when you start throwing wrenches. Take your time and start with a small bit centered as perfectly as you can in the broken bolt. When you've drilled through the offending fastener, step up to the next size bit, then the next. Eventually the remains of the bolt will spin out with the left hand bit. The bolt might be paper thin by the time it comes out. Sometimes I've spent 2 or 3 evenings removing just a couple of bolts, but I urge you to take your time and not get in a hurry. Been there, done that, thrown the wrenches.

 

I generally despise let hand drills and "EZ outs" because when the bolt breaks off below the surface it's screwed into, inevitably it is not an even surface that you can pilot a drill bit in the center of the bolt, whether in a clockwise or counterclockwise rotation. Obviously not wanting to drill into the side of the hole to destroy the threads, you drill a smaller hole with the drill bit, which requires the use of a smaller extractor. But with meat left on the broken bolt, it generally doesn't want to budge, and the smaller extractor is probably undersized for the bolt you're trying to remove, which then increases the likelihood that you're going to snap it off in the broken bolt.

I've also questioned the concept of the EZ out since even if everything goes right, what is really occurring is that the wedge shape of the extractor digs into the broken bolt and further increases the force outward on the broken bolt. I can only imagine that this is trying to expand the broken bolt, which is only tightening it in the hole as it further binds the threads of the bolt into the threads of the hole where it busted. That's counterintuitive.

I have used EZ outs successfully before, but I have snapped them off easily as many times or more. The "nut welded to the broken bolt" trick has been more effective, but when push comes to shove, the things that seem to increase the overall chances of success are dissimilar metals between the broken bolt and the hole it's in, and the application of heat. The welding trick does that just by way of process.

I'd also add that the late Flatdog here on the HAMB, showed me a great trick to burn bolts out of cast iron with a cutting torch. It works, and is the best method I have come across yet to get a truly busted bolt out that isn't going to budge otherwise.

 

One thing my gramps taught me many years ago was to not heat around the fastener, but to heat it dead center. It expands the fastener, and fractures the rust in the threads. Do it a couple times, letting it cool off in between, let it cool again, and it will usually come out pretty easily

 

If the corrosion seized full size bolt broke during removal, the high strength but much smaller EZ out or LH drill doesn't stand much of a chance. Until/unless the rust bond is squished or busted.

Bolts can also break immediately because the installation torque was too much, or fatigued over time because they were installed too loose and were subjected to bending or variable tension loads.
Those stub bolts' threads aren't usually sized to the tapped hole, so can unscrew fairly EZ. Then LH drills and EZ outs have a fighting chance.

If the bolt and tapped hole gall ( stainless on stainless can be poison) material starts to "pick up" real quick and form metal nuggets as the bolt is loosened.
https://www.boltdepot.com/Images/Fastener-information/Galling/Galled-bolt-with-removed-nut.jpg

Then it is time to machine off the tapped housing, split the nut, or etc.

 

Nifty idea, I'll have to try that.

 

I have a straight (basically splined) set of easy outs from Snap On that I have used successfully many times. The tapered easy outs are garbage.

 

I've had some luck using a Dremel Tool to make a centered dimple for a drill bit.
Especially good if the fractured stub is slanted.

 

Since I am left handed I use left hand drill bits all the time.

 

Thanks, - a friend of mine rang last year wanting to borrow my easy outs. He was assuming that I had some, and was surprised at my allen key trick. He said he would try it and rang back 20 minutes later, - couldn’t believe that it worked.
My mechanical engineer son watched one day and told me that I was wasting my time.
He too was amazed at how it worked…….
(Possibly some of the secret is in the strength of the Allen key and that you have ‘leverage’ that an ezy out doesn’t have ).

 

In the last 20 years, that's pretty much all I have used. There has been the occasional nut welded to remove something but it's usually my second option.

The posts about shorter bits and the chuck are spot in, too.

Everyone should have a small set in their toolbox.

 

Another thing I've learned over the years (the hard way) is to center punch the broken fastener as close to CENTER as possible, using a magnifying glass if needed. Then use a center-drill to start the pilot hole. They won't flex and move around as much as a standard drill bit will and help to start the hole centered in the fastener.