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Check out his pasta knife video and the one where he uses a stoneware dish to sharpen a dollar store knife. Conceivably one could make a shiv (more practical and sturdy than a traditional knife shape) from pasta and sharpen it with any unglazed ceramic surface. Many of these tricks are already known in prisons, but not sure if anyone has used the pasta one. A thick, sharp pasta shiv to the liver would be a deadly weapon. Skinny, sharp on both edges, and a bit thick in the middle is probably the deadliest shape as it penetrates deep and the wound has a harder time closing up on it’s own vs a very thin, broad blade. You can make a seriously hard baton out of paper when rolled tight enough.
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Isn’t the melting point of aluminum relatively low compared to the melting point of aluminum oxide? Could be he’s using that in some way?
As for the other stuff, I thought he was going to hammer those screws in the handle to act more like rivets. I assumed the reason is he wanted to repurpose things rather than just use the obvious choice. I thing it is more Otaku or irony more than just straight up comedy.
I’d love to make a couple of these as a gag gift. Does anyone know how long would they last until falling apart?
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I watched his other video where he makes a knife out of a stone plate; I want that tiny cow water pitcher and the brush vacuum!
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The hottest part of a gas flame is more than hot enough to melt aluminum, and most other metals. But if you have a big chunk of highly-conductive metal in open air, the heat will escape so fast that I doubt even the parts sitting directly in the flame will get hot enough to melt (660ºC).
If you have two pieces of metal touching each other, without even a single molecule of air or metal oxide in between, then they will spontaneously weld together at any temperature. If it weren’t for the molecules-thin aluminum oxide layer, the sheets of foil are probably smooshed together enough for this to happen. So if, somehow, the one or two molecules of Al2O3 holding the sheets apart at any given point were to move out of the way, it’s plausible that you’d end up with a solid weld at that point. And those welds could join up until you had a solid piece of metal, presumably with a bunch of microscopic alumina crystals embedded in it. I don’t know how or if that could happen, though. It’s unlikely to be a chemical process, but perhaps the surface Al2O3 molecules migrate spontaneously?
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Don’t know if it’s real or not. Don’t know why I watched. Don’t know why I read all the comments. Probably like anyone reading this don’t know why I’m commenting. Hypnotic compulsion encoded in the the clip?
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Ever wondered why British football fans carry newspapers? Yup, that’s all you need to make a Millwall Brick.
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Might be… simpler… to have a “more accommodating” shiv smuggled in via one’s keister.
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No, that’s not how vacuum welding works. Vacuum welding takes a long time, low temperatures and true vacuum.
A natural gas flame can reach around 2,000 °C, several time the melting point of aluminum. I assume the edits shorten the apparent time it’s left on the burner.
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I’m intrigued by his lack of appropriate gear, tools, and workspace. The tiny hammer, the shaky table with the small clamp-on vise/anvil, the ceramic figurine oil jug, the surgical gloves for Petes sake! He’s probably wearing fuzzy ear muffs as hearing protection. It looks like the only thing he’s invested much money in is his sharpening stones. What a (wonderful) kook!
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Wait: Isn’t the purpose of the serrated bit to periodically rip various parts of my hand to shreds? I’m confused.
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Though on the other hand, here is a video of metal being vacuum welded instantaneously at room temperature in open air:
At the atomic scale, if you mash two clean pieces of suitably ductile metal together, the gap between them is too small to admit air molecules, which is functionally the same as the joint being in a hard vacuum. The only thing separating the two parts is whatever oxides or adsorbed gas molecules may be present on the surfaces, and wherever there aren’t any foreign molecules, a weld exists the moment the surfaces touch, since metal atoms don’t intrinsically know what piece of metal they belong to. This applies at any temperature. In real-world cases, there are always some foreign molecules present, and the time taken to form a weld is limited by the rate at which these foreign molecules are moved out of the way (by desorption, or migration over the metal surface, or by abrasion, or chemical processes).
That picture applies equally to vacuum welding, friction welding and forge welding, because they’re all more or less the same thing atoms-wise. If something like that is happening in the video, I wouldn’t call it forge welding or friction welding because it’s not being beaten or rubbed while hot, but feh, it’s all the same thing.
The reason I don’t think it has anything to do with melting aluminium, aside from my post above, is that the metal remains solid, which is a key sign of not melting. If it only melted where it was in the flamelets, then you’d have a stack of foil with a ring of spot welds, but when he hits it with a hammer it sounds like a solid bar.
In any case, I still think the more likely explanation is “fake video”.
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It’s a small price to pay for the hats that protect us.
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It seems that you can, but it’s not easy and requires filler rods
http://www.forgemaster.com/view_section.php?section=37
I’ve seen mokume made with aluminum, but that required a furnace and pressure at heat, not tapping it with a planishing hammer
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I’m a little skeptical that isn’t some other process at work. I was under the impression that it took a while for the intramolecular forces to form bonds. But Cody may be right. I do love his channel.
For instance, his demonstration with the indium blocks at 15:30 in his above longer cold welding video is not cold welding, it’s an example of intermolecular force, probably the van der Waals force.
My field isn’t materials science, but I’d want to hear from someone whose is before concluding whether something was vacuum welding, and I’m almost certain the demonstrations done in open air are not vacuum welding.
It’s certainly possible. But given that an unregulated gas flame can easily reach the temperatures needed to melt aluminum and the apparent work-hardening of the foil into a billet, what is your reason for thinking that?
For my part, I think there’s too little information to make a conclusion, but there’s no obvious reason to assume it’s unlikely the video is real.
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Hooligans, not fans. We managed to get rid of most of them in the 1990s and don’t want them back.
I learned about Millwall bricks during my training to become a steward at Carlisle United. The warning sign was someone carrying a broadsheet who you wouldn’t normally expect to read one, or as my supervisor said
Skinheads are not the Guardian’s target audience
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I do have a degree in chemistry, but I’m not asserting what is happening in the video (if real), I’m just talking about what might be plausible. But it certainly is plausible to vacuum weld metal surfaces without extreme conditions.
The reason I’m skeptical is simply that if it were possible to work with aluminum this easily, it seems like that would be much more widely known. If the result is as good as the video makes it look, then the technique would be extremely useful.
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Mine are in physics, so I’ll take your word for it.
Wouldn’t aluminum be a poor blade material though? It seems like the edge would never be as well aligned as a steel alloy and roll and dull much quicker.
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Sure, it’s a garbage metal for knives or any kind of tooling, but you could make lots of other things this way. If I want to make a custom aluminum part, my only option at home is to use CNC, so just starting with a correct-sized blank would save me many hours of loud machining. It also seems like you could hammer the foil over a form to make solid metal shells, for example.
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