Isn’t that what those leathery welding gloves are for?
Very cool. I know a person who works on guitars is called a luthier, I believe, but what is this, a saxophoneistician?
I swear you are James May in disguise. This is exactly the kind of thing I’d imagine him fixing other than a car…
I can see how you would do that on an exposed setscrew. Usually, the rusting thing I mentioned is done on very small horological screws, where the capacity to tighten is greater than the ability to resist shearing. Ie: someone has snapped the head off overtightening. Maybe on some of it, they did so over 150 years ago, and I’m fixing it now. And the screws you might use this technique on are the smallest screws in the world, 0.25 mm pitch and smaller is normal.
When something with the screw shaft is only ~1mm across, easy outs don’t work. Even hand made boring bars can’t normally cut that small. So you might rust it out. Your screws are gargantuan in comparison, but you could still rust them out, it would just take a long time. It’s really most useful on small, delicate items that you can’t damage at all, no matter what, because they can’t be retapped in the original material.
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Run. Away. Screaming!
(I was never much of a luthier, just a woodwind tech 
horizontal crack repair was always my favorite)
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C’mon, M1 screws are HUGE.
Haha! Not with my flush Erems, you don’t!
This is correct.
I kept thinking about it as remembering the copper is suddenly exposed- but that is only possible as the zinc leaches away, leaving the copper behind. As brass is Zinc & Copper, with traces of some others depending on it’s grade.
Yeah- that sounds really dishonest to do. Like something a jewelry faker might do. Interesting though.
Sounds like manipulating reverse shrink fitting to me. You can join two materials together extremely tightly if you rely on their differing coeefficients of thermal expansion. Simple terms for laymen- steel expands less than aluminum when heated to the same temp. Take a steel pin and chill it, and put it in a close fitting steel hole at room temp- pin will warm up, and expand to fit the hole very tightly. Many things in the world are held together in this way without fasteners.
So you are heating up the screw and plate it is in, then rapidly cooling the screw to shrink it before the surrounding material, freeing it- if you’re quick enough. I’ll admit it- I’ve done this one, and it does work. Works on larger stuff better, to a point.
But you will get burned. Use canned air upside down and you won’t risk igniting the WD-40 first!
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It was used a lot in antiquity. It is still done these days by a few artisans.
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Ahh… makes sense. Could be used to make something look more “gold”, but not hiding nescessarily that there is gold in it. Could go either way really, depends on how it’s marked, like anything. Neat idea though, could be very useful instead of plating- just make the base item from an alloy, and selectively deplete it.
that’s exactly what it is. and the WD40 is only there for very quick capillary action lubrication. when it actually burns it gets… sticky. my yoyo making friends use shrink fitting to get almost perfect weight distribution on their newer models (which i don’t think are released yet, but also aren’t a secret).
(this one is threaded, but just looks cool)
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Very pretty!
I need to make a child’s popup book for makers called “101 ways to remove a screw”
half of them will be real, half will be cartoon violence, like dropping a safe on it
I dunno. Makes me think how cool it would be to find 101 actual working ways to remove a screw.
Could make an interesting coffeetable book or something.
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If we allow variations on a method to count as individual ways, it should be pretty much possible.
There are also the hightech ways, e.g. laser ablation or microplasma or laser-welding a stick on the stub.
And then there are the exotic ways, e.g. a tactical nuclear demolition munition; has the disadvantage of removing the whole object, though. But the screw gets removed too.
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i would buy that book.
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I use an older pair of flush cutters for small screws and needle nose or regular visegrips for larger screw heads. BTW flush cutters are what that pros use to cut leads of components after soldering to a pc board they cut the lead close but donot pull up on the lead like diagonal cutters do. If you build stuff on pc boards, perf boards etc. do your self a favor and get a set of flush cutters the work looks better and it avoids damaging the pc board like diagonal cutters can. Diagonal pliers can exert a lot of upward force on the wire they are cutting leading to either immediate or later failures. I learned it the hard way back in the late 1960s while building a Heathkit Ham radio tranciever, it took a long time to find the crack around the solder pad where it connected to the trace.
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Ha, yes! Been there, done that. <sigh> Pull the manifold off the V8 block, and off to the machine shop with the electron drill.
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Huh, interesting. What’s the difference between flush cutters and diagonal cutters? I’ve used both, I think, but I never realized they weren’t just different names for the same deal.
I had to change the plates on my car recently, and to my disgust found that the screws were center-pinned torx bits. Fortunately the screws themselves were gigantic. So I just took a .33mm metal bit, drilled a hole horizontally straight through the screw heads, threaded a thick sewing needle through the hole, and just twisted the screws out.
It’s gotta be completely illegal to use something like a “security screw” on something that is mandatorily changed like a license plate.
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Your chemical method reminds me: If you have a stuck aluminum screw in a piece of steel, you can “melt” it out with just a small droplet of mercury.
Mercury reacts with aluminum to turn it into the consistency of wet paper towels.
You can see a demo on youtube where just a tiny itty-bitty drop of elemental Mercury is placed on the top of a coke can, and in a few minutes the whole thing collapses under its own weight. The demonstrators can then just pull the can apart like a napkin.
I don’t know how badly Mercury affects steel though, but it would seem to be less than aluminum seeing as they did the demo in a steel bowl, instead of glassware.
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3D scan the stripped hole, and then alloy-sinter-print a corresponding bit that fits perfectly?
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It’s easier to weld or braze some material in, then drill and tap it conventionally. Or drill-tap a bigger hole, screw in a bolt, tighten or glue or weld it in place, then drill-tap the hole in the bolt.
Steel is pretty resistant to mercury. Not dissolving, not being wetted.
Glassware has an unpleasant tendency to shatter. Mercury is heavy and if you get it splashing against the wall of the vessel, and the vessel is brittle, you can get quite a surprise. On the way from my high school there once was a place with mercury balls all in the pavement, when somebody “borrowed” a glass bottle and it shattered in his pocket during walking; I didn’t witness the event itself but heard the story and saw the balls. That was early-to-mid-90’s, plusminus.
That’s why the airlines hate it being transported in airplanes. Even a relatively small spill can cause a substantial writeoff of an airplane.
These faults are hard to catch. Sometimes it pays to resolder all the suspect joints or reflow the entire board; can be faster than trying to track down The Bad One.
It might seem better to reflow the whole board but actually finding the defect and correcting it is much better. It doesn’t take a lot of time to inspect the board with a 10X jewelers loupe and it finds the cold solder joints and pcb cracks. I repaired all kinds of electronics for nearly 50 years and I found that going over the board and finding the cracked pc trace or cold solder joint is the only way to solve the problem forever. It takes less time than having that piece of electronic gear boomerang back into your shop because the cusomer had intemmitent problems with it again. Taking a “shotgun” approach as you suggest may or may not correct the problem because you never actually located the problem in the first place.It is much more profitable to fix the problem correctly the first time. It also makes for more satisfied customers and they send their friends, family and coworkers. Those referred customers are the best customers you can have because they come in knowing they are doing business with the best repair tech for their needs. That being said sometimes you need to resolder the whole board because the wave soldering machinery did a crappy job but that is a not a huge percentage. I always tried to keep the recalls percentage low since you don’t get paid to fix the same problem again (It also lets you sleep better at night which is important).
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