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Proteus Technology: New Material Is Strong, Light and Non-Cuttable

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Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#201

Post by willyt »

bosswipe wrote: post #155
chongli wrote: post #130

Earlier quoted context omitted.

I’ve watched a bunch of lockpickinglawyer videos and there are locks he cannot pick at all, and locks which take a hell of a lot of punishment from a Ramset gun. It’s not out of the realm of possibility that you could build a bike lock which would effectively deter thieves. After all, it doesn’t have to be indestructible, it just has to convince the thief that your bike is not worth the time and risk of attracting at…

One painful lesson I learned after having an expensive bike with an expensive lock stolen is that as you harden the lock at some point the weakest link shifts from being the lock to the thing the lock is attached to.

Get some brightly coloured spray-paint. Neon pink, gold or whatever. Paint the whole bike with it, obviously try not to get it in the mechanically sensitive parts but otherwise coat the whole thing. No-one is going to steal that, it will still ride just as well.

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#202

Post by Brian_K_White »

kbenson wrote: post #116
sk5t wrote: post #112

Earlier quoted context omitted.

It does both!

My point is that if you look at that definition of "cut", it's not just rendering one item into two pieces, other wise tearing or cracking something would be cutting it, and those aren't cutting either. I doubt this material is impervious to shear force, or being lowered in temperature until it's brittle and cracked. But those aren't methods of cutting .

I don't see the distinction. Everything but shears removes material at the cut. A plasma cut is no different in that respect from a saw, grinder, water-jet, laser, torch.

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#203

Post by Kednicma »

chongli wrote: post #130
sudosysgen wrote: post #110

Earlier quoted context omitted.

They just use a Ramset gun. Thieves are generally quite smart. The dumb ones tend to end up in prison, or worse.

I’ve watched a bunch of lockpickinglawyer videos and there are locks he cannot pick at all, and locks which take a hell of a lot of punishment from a Ramset gun. It’s not out of the realm of possibility that you could build a bike lock which would effectively deter thieves. After all, it doesn’t have to be indestructible, it just has to convince the thief that your bike is not worth the time and risk of attracting at…

This is a little disingenuous. There exist locks that he cannot pick, but the vast majority of his uploads are three minutes or fewer and include a successful picking attempt. More on-topic for this thread, a common LPL theme is that bike lock chains are made of high-quality hard-to-cut material, but the lock cores are still often commodity parts which are picked open by standard techniques and tools.

I would say that much more important for discussing LPL is that he has immense real-world experience, equivalent to a master locksmith, and he builds his own picks. I am not the best lockpicker, but I bet that even I could open bike locks as quickly as he does, if only I had "the tool that [he] and BosnianBill made" in my fingers. Indeed, the community has talked quite a bit about the tool, and perhaps we'll get a 2020 gift in either a commercially-available version or public specifications for building them at home [0].

[0] https://old.reddit.com/r/lockpicking/comments/atf3ef/so_that...

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#204

Post by jayjader »

taneq wrote: post #165
sethhochberg wrote: post #80

Earlier quoted context omitted.

Even without a pre-cut rack, its pretty common that whatever you've locked up to (sign post, bike rack, parking meter, handrail, etc) is a lower grade of steel than the ultra-hard stuff on the shackle of a good bike lock or chain anyways. No need to pre-cut that cheap galvanized steel sign post if you don't want to, a thief would have no problem getting through it quickly if something attractive was locked up. I'll u…

> its pretty common that whatever you've locked up to (sign post, bike rack, parking meter, handrail, etc) is a lower grade of steel than the ultra-hard stuff on the shackle Way back in highschool this always used to baffle me. You'd get kids spending $50+ on super fancy locks for their lockers, but all these locks equally were fastened to the locker with a flimsy little hasp that you could cut with a pair of tin sni…

Often, and notably in the case of school lockers, there is a huge difference in bypassing a lock using a method that leaves traces of your passage and using a method that renders your infraction undetectable - or at least undetected.

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#206

Post by db48x »

throwaway9d0291 wrote: post #169
db48x wrote: post #68

Earlier quoted context omitted.

This material is completely unsuited for making shoe soles or elbow pads; it's a two-inch-thick plate of aluminum foam with half-inch ceramic spheres embedded in it. Around that they welded steel plates to give it a uniform surface. It'd make a very heavy but uncuttable door, but you can't make hinges or locks out of it. It would be a good material to make safes out of; those already have thick walls of composite mat…

I think that's a premature judgement. Is there any reason to think that it's impossible to scale it down? e.g. for PPE, 5mm ceramic spheres in a 1cm-thick Aluminimum foam with some 1mm steel plates on either side?

Yes, there is. They hypothesize that this material works because the ceramic spheres vibrate inside the flexible matrix of the aluminum foam, damaging the grinding wheel. A thinner foam will have less ability to flex, and smaller spheres will be have less momentum to use against the wheel.

Plus, if you watch the video of them grinding the material (https://static-content.springer.com/esm/art%3A10.1038%2Fs415...), you can see that the grinding wheel penetrates over half an inch before it begins to be destroyed.

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#207

Post by senderista »

hwillis wrote: post #148
almost_usual wrote: post #129

Earlier quoted context omitted.

They don’t mention what kind of blade was used in the experiment? Interested if it was a diamond blade or a conventional blade. When pausing the video it looks like a conventional cut off wheel.

It's an alumina fiber reinforced blade, same ceramic as in the material. It's the most common grinding wheel material. Diamond blades are not especially good at cutting. They only used when absolutely necessary, ie when your material is extremely hard. Diamond sublimates at low temperatures, it dulls quickly because of the fracture planes, and it's so weak and brittle that only tiny grains can survive being used to c…

I use diamond metal blades because I don’t want my blade turning into shrapnel.

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#208

Post by [deleted] »

db48x wrote: post #206
throwaway9d0291 wrote: post #169

Earlier quoted context omitted.

I think that's a premature judgement. Is there any reason to think that it's impossible to scale it down? e.g. for PPE, 5mm ceramic spheres in a 1cm-thick Aluminimum foam with some 1mm steel plates on either side?

Yes, there is. They hypothesize that this material works because the ceramic spheres vibrate inside the flexible matrix of the aluminum foam, damaging the grinding wheel. A thinner foam will have less ability to flex, and smaller spheres will be have less momentum to use against the wheel. Plus, if you watch the video of them grinding the material ( https://static-content.springer.com/esm/art%3A10.1038%2Fs415... ), y…

[deleted]

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#209

Post by db48x »

pmlnr wrote: post #171
db48x wrote: post #59

Earlier quoted context omitted.

Not really. Armor made of this material has to be much thicker than ordinary steel plate. Furthermore, ordinary steel plate is entirely effective against swords, except at the joints and articulations.

> entirely effective against swords Against the immediate cutting, probably. But it also bends. And with bending, it could damage you really bad, including the part that removing them could become quite a trouble.

True, but cutting is what we're talking about here, and since the material they've invented in this article is made of aluminum foam, it'll bend even easier than steel of the same thickness.

Re: Proteus Technology: New Material Is Strong, Light and Non-Cuttable

#210

Post by cainxinth »

Jedd wrote: post #44

> The freefall of grapefruit from 10 m does not damage the pulp[1] because pomelo peel consists of vascular bundles and an open-pored cellular structure with the struts made of parenchymatic cells. I have a Marsh grapefruit tree, fruiting now (southern hemisphere) as it happens, and I note that it produces particularly pithy progeny. (Ignoring for the moment that Pomelo is one of the parents of the modern grapefruit.…

"I'm now consumed with curiosity why this plant has evolved to have this feature."

Grapefruit didn't evolve naturally. In fact, it's only a couple of hundred years old. It's the way it is because of human intervention.

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