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Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

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Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#91
post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

The younger guy in this clip actually ended up retiring because he got brain damage in a contraption he designed for this show.

https://www.bbc.com/news/uk-58762935

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#93
post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

And he still has 10 fingers! Unlike, for example, Mark Pauline ( https://en.wikipedia.org/wiki/Mark_Pauline )

A bit of a nervous twitch perhaps.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#94

Earlier quoted context omitted.

> much like a jet of hot water melts through a block of ice cold water can cut through steel also... https://www.youtube.com/watch?v=v0NVOThRooE

Waterjet cutting uses water to propel a powder which acts as an abrasive, like an infinite stream of sandpaper. I don't think water by itself will achieve much.

Waterjeting without abrasive is a thing, it's used for soft materials like rubber... and there are some companies marking higher pressure approaches for metal (though usually with tiny amounts of abrasive rather than none at all).

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#95
post #62

Earlier quoted context omitted.

It's all fun and games until you realize your country has no deniability about being at war with Russia.

I think the line is when your troops shoot their troops. Providing weapons has been a US-Soviet past time for the whole Cold War. In this case, I think the US could have even moved in troops without being at war, early in the invasion. It just needs a pretext. By far the best response a week in, when Russia claimed chemical weapons, Nazis, etc., would have been to send in a multilateral force to investigate Russia's…

If you look on various dating apps big in Ukraine right now, you'll see there are a lot of Americans new to Ukraine right now.

I've got a feeling we might be pulling a Russia... Ie. None of our troops are there officially, bit there's an awful lot of troops volunteering and 'on holiday' and 'advising' there.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#96
post #91
post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

The younger guy in this clip actually ended up retiring because he got brain damage in a contraption he designed for this show. https://www.bbc.com/news/uk-58762935

This is bizarre. He knowingly, purposefully took the place of a crash test dummy? Why?

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#97
post #21

Earlier quoted context omitted.

The explosive is stable (small cubes of most plastic explosive can even be lit on fire and act as fuel). But there is still danger in correctly handling/connecting the detonator. I'm not sure, but I thing the acceleration charge might be a less stable type as well (obviously they aren't going to give us step by step instructions).

> (obviously they aren't going to give us step by step instructions). nitrocellulose is very simple to make and detonate... and is also very stable.... I don't see why we need secrets... I played with that stuff when I was a teenager

I assume it helps to narrow down the list of suspects if/when the (guarded/secret) knowledge is used for nefarious purposes.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#98
post #41
post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

"What makes me a good Demoman? Well if I were a bad Demoman, I wouldn't be sitting here discussing it with you, now would I?" One of the silliest, hilarious but on point thing I've ever heard uttered from a video game character

"Hey look, buddy. I'm an engineer: that means I solve problems.

Not problems like 'What is beauty?' Because that would fall without the purview of your condundrums of philosophy.

I solve practical problems..." https://m.youtube.com/watch?v=SNgNBsCI4EA

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#99
post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

Count the fingers. More than 8 is probably OK. age may be a drawback, one gets too old to meddle with some of the more fun things eventually.

There are old people who use explosives. There are bold people who use explosives. But, there are no old, bold people who use explosives.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#100
post #53

Earlier quoted context omitted.

Great find @ 0:40. The only thing it doesn't convey very well is the older man's explanation of the copper spear curling outward on itself. From the simulation, it seems like it is just punching through and maintaining its rigidity somehow.

iirc, nothing is rigid, it's just very high energy jets, so they don't deform much. like particles in water jets cutting steel.

Fun fact: water doesn't actually do the cutting, the water is just a medium for carrying an abrasive dust (ruby/sapphire/diamond) that abrades the steel.
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