Hydraulic Press | Prince Rupert Drops | Remake | Safe Tails

When it comes to hydraulic press YouTube channels, I'm more of a Hydraulic Press Channel guy than I am a PressTube guy. I'm particularly fond of the destruction of a hockey puck and of the vicious clay creatures that are stopped from wanton murder at the end of each video.

But I am willing to watch the derivative PressTube when they come up with something creative to destroy. In today's video, the PressTube folks destroy a Prince Rupert drop...or two...or ten. And, in the process, they also make some pretty big dents in a chunk of lead.

Tempered Glass Breakage

I'm always impressed with the surprising strength of tempered glass - and the willingness of people on YouTube to do stupid things without gloves.

When we discuss the strength of tempered glass in our summer workshops, occasionally a camper will ask why we would use such glass as a cutting board. If a nick on the edge (or especially the corner) leads to spectacular failure, why would be take a knife and go at the surface of the glass?

Because this video. That's why.

Tempered Glass Tests

"Breaking stuff for the sake of curiosity makes me happy."

Yup...

I had a camper in Provo this past week offer up a 4'x8' sheet of tempered glass for us to break. Seems like he had three of the sheets unused in his living room, there from a previous owner. The camper decided better of the breaking, though, but did promise to film, post, and share the video if he ever got around to breaking the sheet himself at a later date.

In this video Jason Patric our host throws a baseball, hits a golf ball, and finally shoots a metal bb at the glass to finally break the sheet. At 3:40 then the video explains why the tempered glass is so strong. In the end the host takes a tiny hammer to the edge of the sheet.

Crash Test 1959 Cheverolet Bel Air VS 2009 Cheverolet Malibu (Frontal Offset)

Gimme a great, old, heavy car if you're going to whomp me with another car.

Obviously that heavier car will have worse gas mileage, but the mass of the old car will mean that I'll be that much safer.

I swear that my dad said something like this when I was getting my first car. He wanted his boy to be safe, gas mileage be damned.

Turns out that maybe Dad was wrong. Yes, the old cars had more mass, but they also had old engineering. New cars are much, much safer because of great new materials and because of great safety engineering...and Ralph Nader.

Boeing 777 Wing Test

This one isn't for the faint of heart of the afeared of flying as the engineering team of Boeing pushes the wings of the 777 far past their design limit load.

The wing shatters at 154% of the strongest forces that the wing would ever be expected to encounter during a flight - and certainly well beyond anything it would encounter during a routine flight, and when it shatters, it shatters. This video then replays the shattering - with the echoing "154" - over and over again.

Oh, wait...


[Spoiler Warning]

How much pressure does it take to crush a concrete cylinder?

Great under compression, lousy under tension...concrete has its strengths. That's why we use it to build dams, buildings, anything that needs to withstand something really heavy pushing down on it.

This test, applying a million and a half pounds of pressure to a concrete cylinder isn't something that most of us - a few matsci teachers in Washington state, not withstanding - can't do in our classrooms, but it's the kind of thing that's well worth testing for a roomful of visiting kids and parents at your engineering open house.

Yeah, there's science there, but there's also wanton destruction. That's always cool.

Mystery of Prince Rupert's Drop at 130,000 fps - Smarter Every Day 86

Prince Rupert's drops (also known as dragon tears) are beautiful explorations of tempering glass - like the Corelle plates that we demonstrate in the first year summer course - using the opposing stresses of the outside and inside glass to create phenomenal strength.

This video does some pretty stunning things with high-speed photography, showing the shockwave travelling down the tail of the drop to the head at over a mile a second.

The video explanation - using red-, white-, and blue-shirted versions of our host - is absolutely brilliant, doing a better job of showing the stresses than any other video that I've seen. Marvelous...stunning...

And, at 4:33, there's a tiny bit of type at the bottom of the screen that tells the actual amount of pressure involved in the Prince Rupert's drops.

Great, great, great video!

Why aren't they wearing gloves, though?

Here's a similar video from Theodore Grey's Popular Science column, Grey Matter.

Jet engine testing (superalloys)

I know a couple of our master teachers who should NOT watch this video because of their little fear of flying thing.

I, on the other hand, have no fear of flying at all. I don't fly very often - about twice in a typical year - and am totally relaxed when I am flying because I know that airplanes are overengineered to the point of ridiculous safety. I hope...

This video shows Rolls Royce testing one of their jet engines in the case of engine turbine blade during an event of catastrophic failure. The super slow-mo footage of the turbine going off balance and recovering is actually terrifically reassuring to me as a passenger.

Polar bear shatters glass

Here we see a clearly devious polar bear conducting a little destructive testing on the window of his enclosure. Lucky for us two Dutch documentarians were there filming in front of the aquarium (is that the correct term for where polar bears are kept?).

I saw something along this line a few years back when they were installing the new polar bear exhibit at the Cincinnati Zoo. Apparently the forklift tapped the glass a bit more firmly than intended, shattering the glass in a gorgeous spider-web pattern.. The zoo left the glass up initially with a note explaining that the shattering was a show of how well the glass was designed. Even though one of the panes shattered, the other panes laminated together had held the strength.

I'm thinking that we're got a composite of laminated glass here. With the shattering, spider-web pattern, I think we might have tempered glass, too. Thoughts?

Source - care2