MOLTEN GLASS VS Prince Rupert's Drop - Smarter Every Day 285

Do you know what this is? If you do, you will be very excited about this video if you don't know what it is. Let me catch you up. This is called Prince Rupert's Drop and is created by

drop

ping

molten

glass

into water. Now, when that happens, something really interesting happens in materials science, where on the outside there is an extremely high compressive stress. But the interior of this

drop

let is under extremely high tensile stress. What that means is that you can hit the tip here with a hammer and it won't break. It's

glass

, but it doesn't break.

You can even hit it with a bullet. And I have done it here on this channel and it destroys the bullet. But if you cut its tail, it explodes. I get very excited when I do this. Explodes. See this. Now I have a mess I have to clean up. So a

prince

. Oh, wow. It's

every

where. That little moment where it explodes. I wanted to capture that. So what I did was I threw a blob of Prince Rupert into epoxy resin, and then I smashed it up and tried to capture the exact millisecond of the explosion. Now, a lot of people watch this video and say, Oh, well, you did it wrong.

You didn't use the right epoxy, you didn't vacuum the gases properly. And these are fair questions. I mean, look, it's turning yellow. It's not as good as I wanted it to be. But there was one person who saw this and asked a very different question, and that was Cal Breed, the man who made the original Prince Rupert pitch that I featured here on Smarter

every

day. Cal's question was: Should you use epoxy? Couldn't you do it with glass? To which I responded: What? That? Think about it. Prince Rupert's drop is glass. Putting glass inside

molten

glass has to change things, right?

It is a very difficult problem. So today on Smarter Every Day. We'll delve into the mind of an artist who understands the material properties of glass far more than any engineer I know. And let's see if we can put a drop of Prince Rupert on molten glass and break it. Let's get

smarter

every day. This is Cal. He is the owner here at Orbix Hot Glass. What we are going to do today is have fun. And I have fun doing strange things. And I have a great team of amazing people who like to do weird things with me.

We've made it clear that the Prince Rupert drops, I want the ice blue one, so we're going to buy an ice blue glass. We buy colored glasses and then we can break off a piece, put it here and heat it to a thousand degrees. That is, we parked it in the garage. So this is our garage. It is hot enough to prevent the glass from breaking, but not hot enough to cause it to collapse. In a minute we will collect it from the end of a rod. Heat it up, preheat it a little bit more in that top corner.

What do you mean by that up there? Yes, in the top left corner, that will be the hottest area. Yes. And then we'll take it out and put it here, which is closer to 2000 degrees. This is what we use when preparing anything during the reheating process. You can't just do it all at once and be done with it. We're going to heat up that blue, make it in small pieces so we have several tries because the colored glass, for some reason, doesn't want to turn into Prince Rupert drops. We can make the whites in a small bucket.

They can hit rock bottom and they are fine. But with colored ones, if they hit the bottom, they usually break. Jill, for some reason she has a special ability. We found out that she has a higher percentage at this time. Do you have the magic touch for color drops? -I guess so, yes. What is the secret? That? I am not. I'm not sure. She's just lucky. -You only know what happens. I can just do it somehow. Yes, I have a higher success rate. That is incredible. Well, do you see what's happening here? We are already learning that these artists have a sensitivity to glass that an engineer does not have.

They understand it in a more intimate way. You heard Jill there, who is Cal's apprentice, talk about how she's able to do certain things and she can't really articulate them. She just feels it. She knows what she's doing. So when I think about this, this is just clear glass. When I see this, it's colored glass. By the way, they didn't do this. They make much nicer things. Then I only see colored transparent glass. But these artists see temperatures and stickiness at certain temperatures. And they have an intimate knowledge of how this works, which is fascinating. So today we're going to work with Jill, who you met there.

We have Eric, Lily and Bodi. These are all people who work with Cal, which means they are learning just as Cal did. Cal has apprenticed all over the country with some of the biggest names in the glassblowing world. It's great to see how this knowledge is transmitted through exploration. And Cal explains here what he and his wife Kristi were thinking when they opened the studio. When we built the store, we wanted to make sure it was like a mad scientist's place. Then you come up with ideas and we try to do it. Similar to what we are doing today.

It's a process of learning to explore, to learn, and then you have your ideas and you come here and try them. Alright. We now know that glass behaves differently depending on its color. So I asked Cal to explain some of these colors to me. Yeah. So this is like an ice blue. You can see how beautiful that blue is. These are very dense bars of colored glass. So if you were to use emerald, it is so dense that it almost looks black. Good. -Well. That's why I chose this ice blue. I love this color anyway, but it's more sheer.

A little later I explored these colors further with Eric, who explained to me that the physical properties and color itself are not only a function of the chemicals within the glass, but also how you heat and cool it. Coppery ruby, this is a very interesting color. This will become completely clear when you are working on it. Completely. And then once you put it in the oven, it will turn blood red. And if you heat it too much, sometimes it just clears up. It is a very strange color. I had never heard some of these words. -Eggplant.

It's like a purple. Uranium is, Oh, no way. -Out, is it real uranium? -Yeah. Yes, good. So to make the individual Prince Rupert drops, they need to break that piece of blue glass they had been heating up in the garage. And to do this, they fix a solid, thin metal rod using already molten glass as glue at the tip. That grabs the blue piece. And then they put it in the glory hole, heat it up even more, making it malleable. They then form individual balls that they can break in a really interesting way. So you broke it with a mechanical vibration.

Every time we make a piece, we eventually have to get it off the blowgun or punty rod. So we're going to create a weakness, you know, that normally we can get temperature shock. And then, umm, put some water or a cold tool on that weakness. -Then, and then, touching it, break it. -So he's doing the weakness now. He's yeah, well, he's creating a tight spot to create a good weakness. Yes. -A concentration of stress. So engineers and scientists think about materials in a certain way, right? They have aluminum and steel. And if you pull and push these things, they have certain things called a stress-strain diagram.

Steel, you're going to pull on it and eventually it's going to give and then it's going to break. Aluminum does the same thing, but a little differently. Glass is different. It does not give or stretch over time. It breaks because it is brittle. Glass artists are always thinking about that point, the point at which the glass breaks. Sometimes they try to avoid that, like in the middle of a big piece. And sometimes they try to create that. But there is more to this, because they are moving from liquid glass to solid glass. You've seen a graph like this before, right?

This is the phase diagram of water. We can boil water from liquid and turn it into gas. We can freeze water and turn it into ice. Good? We can move on to the solid part of the graph. This is how I always understood how matter works. You can move around this graph by changing solid, liquid or gas based on pressures and temperatures. Well, yes, that's true for water, but it's not true for all materials. Water has what is called a first order transition. Let's make a graph of viscosity versus temperature. If you have solid ice and you heat it to liquid water, that phase transition happens very quickly over an extremely small temperature range.

That is why water is called first-order transition. Glass, however, is a second-order transition, meaning that the phase change occurs gradually over a wide temperature band. And you would think that the graph of that would look like this: linear, but it doesn't. It works like this: here in the vitreous region there is cold, solid glass. But as you heat it up, the glass transition starts and you fall off and the viscosity starts to change dramatically and then all of a sudden it stabilizes in a rubbery state. This is known as the rubbery plateau. More heat is added and the rubbery plateau falls away and begins to flow in what is called the rubbery flow region.

If you add even more heat, the glass will begin to flow like a liquid. Look at this curve. Glass artists know how to use this curve to make glass do exactly what they want. If you were a glass artist, where would you like to work glass? For me, it would be on the rubbery plateau. It is a relatively large temperature range that gives me the same physical properties. That's great, right? So when a glass artist takes his work out of the kiln, there is a certain temperature, right? And then it starts to get cold. And then they have a certain amount of time to work it until it returns to the glass transition region.

And then they can't work anymore and they have to put it back in the oven and move it down the rubber plateau, and then they go back and forth and that's what they're doing. They are controlling the viscosity by managing the temperature of the glass. They don't need to know these graphs to know what they are doing. They know it in their soul. Like engineers, we think about stress-strain curves and think, Oh, the glass is going to break here. Well, the glass artist is managing all this with the temperature of the material itself. So they go up and down the curves all the time and just do it.

So I want you to think about this curve, because that's how I have to understand it. The team's first step is to do the Prince Rupert throws. It worked? Oh, wow. Yes. -That's a beauty. Oh, that's so beautiful. -Yeah. Now we have this beautiful installment of Prince Rupert. How do we achieve this in molten glass? The obvious answer is that we need it to be transparent. Whatever we're going to hold the glass for. Therefore, it has to be a glass. And then Cal explained to me that he can't just grab a glass off the shelf and pour molten glass into it because the temperature difference will cause it to explode due to thermal stress.

So what Cal decided to do is create this glass while he prepares everything else. So it will be warm and the temperatures will be similar and everything will turn out wonderfully. And the process of how he does this is amazing. So what we're going to do, you won't be able to do unless you have multiple artists doing different parts of the process. That's right? Yes. You have to have a team for this. There is no way you can do this alone. Really everyone already has a great knowledge of the material, so this only helps us learn it better.

I think we should try it. -Well. Sounds good. So the first step in making a glass is to gather the glass in the liquid flow region in a blowtorch. Cal then takes it out of the oven and cools the blowgun where he can hold it. And then he does this. That?! Did you see that? Back that up. Cal puts some air into the glass and then caps the end of the tube with his finger and then the heat of the glass causes the gases to expand and does all the work for him. He used the ideal gas law to blow up the glass.

That is incredible. -We're just going to meet one more time, please okay. arrest. So at this point you have a glass sphere and now you're going to straighten the edges and turn it into a cylinder and flatten the end. Look how they do this. And you're thinking about temperature and thickness and things like that right now. -All of this. Yes. Stop. Well, Eric, feel the heat from down here and we'll let it out a little. So it will only warm it superficially. That way we can, ah, stretch it from the shoulder. We have made a kind of wide shoulder.

Now let's stretch it down. So once again, the heat differential influences how it is shaped. Well, let's see how we had this coldness. I was able to grab the tips of these and asked him to inflate them and the glass here exploded. You made it a cylinder. -Yeah. So now it will heat it up even less. So he's doing it the other way around. Good? And so this part is cold and this part is hot. So this part is already solid. So you can take your tongs and put them down there and push down and form the part that's the hottest.

They are in different parts of the flow regime on that curve, which is surprising. In addition, the thing is rotating because this part that is here and that is more fallen wants to fall. This is incredible. So now it's going to heat up just the base so we can flatten it out andteam for an afternoon or something. I would like to tell people about your website and where it is located so they can contact you to commission your work. I have nothing to gain from telling you to go to calbreed.com or orbixhotglass.com. This is just me trying to make good on an offer I made to a friend 11 years ago and I think it's amazing.

And thanks to the patrons for allowing me to make videos like this. If you want to support

smarter

every day, you can do so at patreon.com/smartereveryday. That's all. I hope you enjoyed this. Visit Cal's website, calbreed.com. It's absolutely phenomenal. This thing is beautiful. If you want to see, maybe he has a few more that he can make and post on his website. That's all. I'm Destin, you get smarter every day. Have a good.