Removing broken fasteners or stripped out setscrews

[jmorris]

I have removed hundreds of broken and stripped fasteners over the years but never did a step by step. Also a number of methods like EZ out’s of different styles, left handed drill bits, machining and metal disintegration but my go to is a TIG welder and a nut, if they are a weldable material and not too deep.

I have successfully removed down to #2 screws and down to a #5 set screw with the method.

#1 rule of removing any fastener is to not do a thing to make things worse than they already are. Very important, you drill an off center hole, then break an ez out off and I’d tell you, you should have come seen me earlier.

Any way, a stud broke off and they thought it just cam out so they stripped out the threads against the remaining stud before things were tight.

So a stud broke off down in the part that is as difficult to access directly as it is to remove.




Used ER70s filler to weld to the stud and bring the puddle out side of the head, to the point I can set a nut on it and creat a “bolt”.



Then weld a nut to it and put a lot of heat into it. This expands what is stuck in the part as much as possible.




Once it cools I put some tension on it, not much but looking for the point it moves as it cools, then work back and forth, penetrating oil is helpful once it starts moving.



Ready to reassemble.


You can see the depth of the broken stud, once removed because that’s how much weld bead vs threads there are.

 

[jmorris]

Went looking for the #5 set screw I removed from a Novak sight someone had used red locktite on and subsequently rounded out but couldn’t find it.

I did find this one, where I used the technique to remove a portion of a tiny drill bit broken off in a part.

Bic ball point pen for scale.

 

[film495]

I've found small masonry chisels will grip the head of a fastener, if the normal fitting is stripped, bungled - the chisel will grip the metal, and you can get some torque on the head and many will spin out eventually with this method. Just angle it to spin the head and bite down into the metal. Penetrating fluid and the shock of the hits/taps, also helps loosen the bond of the fastener. The last one I did this with, it was because an easy out - snapped off in the bolt, and about 3 minutes with the chisel and hammer and the fastener was out.

 

[WestKentucky]

I like your welding method. Totally not feasible on guns due to size, but to date my best was a 1” bolt that got broken off because it was stuck and crosspinned. Like a lot of shoulder bolts it broke off at the shoulder. Once I got the cross pin out I drilled the original bolt head/shoulder out and stick welded it back into position. With heat, oil, and being very careful, it broke loose and came out.

 

[wiscoaster]

Wow, I sure endorse your rule #1, having broken it myself often enough to know why it's #1!! Thanks for the tips. None better than learned by trial and error.

 

[Obturation]

Broken bolts can be a booger. I do lots of bolt removal for my job (auto mechanic in the rust apocolyptic area of the country) heat, vibration and impact are good. Tiny bolts I will typically put whatever part is fastened there over the hole as a guide for the drill bit, keeps it centered and prevents some headache . it's pretty common for me to weld a nut to what's left and that's always my first go to, especially if it's a ferrous bolt threaded into aluminum as the mild steel filler material won't stick to the aluminum .
Good write up, op. It's so common to see broken automotive fasteners around here , gun fasters make me cringe but I've been successful removing them too. Broken bolts are a way of life for some of us...

 

[earlthegoat2]

Easily the best method and one that as I gained more experience, became my first line of attack instead of my last.

As another observation, When a screw is stuck and the first advise is to soak in penetrating oil, I usually slap my forehead. I’m trying to think of one time where I know that helped all by itself.

More penetrating oil is sold because of this than any other reason I would bet.

To use it like is suggested in the OP is just fine. As a first line of attack though, is usually a waste of time.

 

[jmorris]

Totally not feasible on guns due to size,

I have removed set screws and rounded Allen fasteners using the method. The #5 set screw in the steel Novak 1911 sight took a steady hand and .030 wire to use as filler rod.

As Obturation points out dissimilar metals are easier because there is less chance of welding to the parent metal vs the fastener but it can still be done.

 

[Howland937]

Broken bolts are a way of life for some of us...

Amen to that.

 

[SGW Gunsmith]

Seems that many of the fasteners commonly used are cheap and purchased from China. The smaller screws do indeed have hex sockets that are easily rounded with a hard hex key wrench.
I've switched over to the "torx" style of screws for sight and optics bases mounted on firearm for the last 10 years or so. Their threads can be torqued, carefully to ounce inches, once cleaned of any oil residue, including the threads they go into and then a drop or two of #242 thread locker will hold those screws in place much more securely.
Over the years the Ruger Mark target pistols front sight has been known to shoot loose quite often, so I've gone to the torx style screw to keep that sight in place:



Done right, they stay in place very well.

 

[Project355]

One time I was working on a CZ-75 (original, marked BRNO), and there is a spring in the mag well held in by a screw that goes thru a half loop in the forward part of the spring. The previous owner had buggered that screw terribly, so I was asked to fix it. Screw not available, but... plenty of meat to drill/tap a new hole for a common screw size. Can't remember if I wanted to put 6-40 or 8-36 in there. I'm thinking it was 6-40, as I had those in stainless socked head screws. At any rate, even though I had it all set in the mill so that there was no way the hole and tap were gonna be misaligned, and even though was was carefully turning the spindle by hand ever so slowly.... "snap".
I died a thousand deaths. Called in a buddy who had several EDM machines at his shop. We took it over, and it was literally a 15 minute burn out with a "wire EDM they had exactly for burning out the center of taps that busted in the injection molds they made. Whew. EDM to the rescue. And... a new tap finished the job easily.

 

[SGW Gunsmith]

Back in the day, when one of the assemblers in the company I worked for at the time, would get a little heavy handed when torquing a bolt head fastener into place and would snap the head off of a bolt. Mostly when they had mistaken and set the torque wrench too high.
I ground many of the carbon EDM tips for "die sinking" so that the bolt could be burned out, then the remnants of the bolt body left behind would be easier to get out. I wish that I had access to that method, but instead, I need to settle for the "easy-outs" when a broken off screw needs to come out after a customer used a screwdriver bit and buggered up a slot, or twisted off a hex head from a socket screw. Lots of Kroil and patience is what I'm relegated to now. An EDM die sinker would sure make the removal sooo much easier.

 

[Kp321]

Don’t bad-mouth penetrating oils, especially Kroil. It doesn’t work instantly which is an issue on timed jobs, but eventually it will soak in. I had to leave a first gen Colt SSA soaking for a month before I could move all the screws, but eventually they all came out with no further drama.

 

[BBBBill]

An EDM die sinker would sure make the removal sooo much easier.

you can always build your own - http://www.homebuiltedmmachines.com/
https://hackaday.com/2016/08/07/hom...-difficult-materials-like-magnets-with-eease/

https://www.practicalmachinist.com/vb/edm-machining/home-made-edm-152388/

 

[SGW Gunsmith]

Don’t bad-mouth penetrating oils, especially Kroil. It doesn’t work instantly which is an issue on timed jobs, but eventually it will soak in. I had to leave a first gen Colt SSA soaking for a month before I could move all the screws, but eventually they all came out with no further drama.

So, tell us. Who has "bad-mouthed" penetrating oils here?

 

[earlthegoat2]

Easily the best method and one that as I gained more experience, became my first line of attack instead of my last.

As another observation, When a screw is stuck and the first advise is to soak in penetrating oil, I usually slap my forehead. I’m trying to think of one time where I know that helped all by itself.

More penetrating oil is sold because of this than any other reason I would bet.

To use it like is suggested in the OP is just fine. As a first line of attack though, is usually a waste of time.

So, tell us. Who has "bad-mouthed" penetrating oils here?

Probably mentioning me. I have been a meckanik most of my life. Most of the time in MI, another fun rusty state. I have no proof but I don’t think penetrating oils do anything by themselves the way conventional wisdom will have you believe. Especially when it comes to breakaway torque. Yeah, yeah, I have seen the so called tests but as folks up north know, those tests do not take into account years and years of salt rust.

The ‘ol acetone and ATF (and plenty of other home brews) is a myth in my world too. I’ve used it and there is zero to no difference. YMMV and I hope it does.

Having said that, the use of penetrants as a post breakaway lubricant and as a LOOONG term soaking oil can and does work. Use of impact/vibration methods can expedite the penetrating speed.

I can count on zero fingers how many times I have had the time to wait out a penetrant. Fora flat rate mechanic, waiting on a penetrant is hilarity itself. Like I said, in MY world, penetrants are a waste of time most of the time.

I do use Kroil and will agree it is a different animal. However it is not magic.