We’re going to take what we can learn from this and apply it to our mission.
Do you know what this is? If you do, you’re going to be super excited about this video. Let me bring you up to speed. This is called a Prince Rupert’s Drop, and it’s created by dripping molten glass down into water. Now, when that happens, this really interesting material science thing happens where the outside is an extremely high compressive stress, but the inside of this drop is in extremely high tensile stress. What that means is you can hit the tip here with a hammer and it won’t break its glass, but it doesn’t break. You can even hit it with a bullet. And I’ve done that here on this channel and it shatters the bullet. But if you even nick the tail, it explodes.
I get really excited when I do this. It explodes. Watch this. And I have a mess. I have to clean up. So a prince. Oh, wow. It’s everywhere. That little moment where it explodes. I wanted to capture that. And so what I did is I cast a Prince Rupert’s drop in epoxy resin, and then I shattered it, and I tried to capture the exact millisecond of the explosion.
Now, a lot of people watch this video and they’re like, Oh, well, you did it wrong. You didn't use the right epoxy, you didn't vacuum off the gases correctly. And these are fair questions. I mean, look, it’s yellowing. It’s not as great as I wanted it to be. But there was one person that saw this and asked a very different question, and that was Cal Breed, the man who made the original Prince Rufus drop that I showed here on Smarter every day. Kels question was, should you be using epoxy at all? Can you do it with glass? To which I replied, What? What? Think about it. Oh, Prince Rupert, drop is glass. Putting glass inside molten glass has to change things, right? It's a very difficult problem.
So they’ll smuggle every day. We’re going to get into the mind of an artist who understands the material properties of glass far more than any engineer I know. We’re going to see if we can put a Prince Rupert Strop in multiple cars and shatter it. Let’s go get smarter every day and this is Carl. He’s the owner here at Orbit’s Hot Glass. What we’re going to do today is we’re going to have fun. And I have fun by making weird stuff. And I’ve got a great team of awesome people that like making weird stuff with me. We’ve made clear Prince Rupert drops, I want the ice blue, and so we’re going to pick up some ice blue glass. We buy colored glasses, and then we can break off a chunk of it, put it in here, heat it up to a thousand degrees. This is we park it in the garage. So this is our garage. It’s hot enough to keep the glass from cracking, but it’s not hot enough that it’s going to slump. We’re going to pick that up on the end of a rod here in a minute. Heated up Pre-Heated a little bit more up in that top corner. What do you mean. Up in there? Yeah, up in the top left corner there, that’s going to be the hotter area. Yeah. And then we’ll bring it out and put it into here, which is closer to 2000 degrees. This is what we use when we’re making anything throughout the process of just reheating. You can’t just make it in one gather and it’s done.
We’re going to heat up that blue, make it into little pieces so that we have multiple tries because the colored glass for some reason doesn’t want to be made into Prince Rupert drops the clear ones we can do in a small bucket. They can hit the bottom and they’re fine. But with the colored ones, if they hit the bottom, they typically break. Jill, for some reason has a knack. We figured out that she she has a higher percentage right now. Getting this for the color drops. I guess so, yeah. What’s the secret? What? I’m not. I’m not. She’s just lucky. You just know what’s up. I have just able to do it somehow. Yeah, I have a higher percentage rate of success. That’s awesome.
Okay, you see what’s happening here? We are already learning that these artists have a feel for glass in a way that an engineer doesn’t like. They understand it in a more intimate way. We’re going to take what we can learn from this and apply it to our mission. You heard Jill, an apprentice under Cal, talking about how she can do certain things without being able to articulate it. She just feels it. They make way prettier stuff than just clear and colored glass. The artists have an intimate understanding of how glass works, and they are learning just like Cal did. When Cal and his wife Kristi started the studio, they wanted to make it like a mad scientist kind of place.
Cal explains that glass behaves differently depending on the color. For example, Emerald is so dense that it almost looks black. Eric explains that the physical properties and the color depend on the chemicals inside the glass and how it is heated and cooled. Copper Ruby is a very interesting color that will go completely clear when worked on and then turn blood red when put in the oven. Aubergine is like a purple uranium.
Engineers and scientists think about materials in terms of aluminum, steel, and stress strain diagrams. Glass, however, is different; it is brittle and breaks instead of yielding and stretching. Artists think about the point at which glass breaks, sometimes trying to avoid it and other times trying to create it. They are also going from liquid glass to solid glass. You’ve seen the graph like this before, right? This is the phase diagram for water, which shows how we can boil water from liquid and turn it into a gas, or freeze water and turn it into ice. This is the way I always understood matter to work, with the ability to move around on the graph based on pressures and temperatures. However, this isn’t true for all materials. Water has what’s called a first order transition, which means the phase change happens very quickly in an extremely small temperature band.
Let’s make a graph of viscosity versus temperature. If you have solid ice and you heat it up to turn it into liquid water, you will fall off the solid part of the graph and the viscosity will start to change drastically, then suddenly it will level off in a rubbery state. This is known as the rubbery plateau. More heat is added and you drop off the rubbery plateau and it starts to flow in what’s called the rubbery flow region. If you add yet more heat, the glass will start to flow like a liquid.
Artists know how to use this curve to make glass do exactly what they want. If you were a glass artist, where would you want to work the glass? For me, it would be on the rubbery plateau. It’s a relatively large temperature range that gives me the same physical properties. So as a glass artist takes their work out of the furnace, it’s a certain temperature, and then it starts to cool off. They have a certain amount of time to work it until it gets all the way back over to the glass transition region. Then they can’t work it anymore and they have to stick it back in the furnace and they move it back down the rubbery plateau, and then they come back and forth. They’re controlling the viscosity by managing the temperature of the glass.
The first step for the team is to make the prints. Rupert’s drops. Did it work? Oh, wow. That’s a beauty. So now we have this beautiful Prince Rupert’s drop. How do we get this thing in molten glass? The obvious answer is we need it to be transparent. So it needs to be a glass. And so Carl has explained to me that he can’t just go get a glass off the shelf and pour molten glass into it because the temperature difference will cause it to explode due to thermal stresses. So what Carl has elected to do is create this glass as he’s getting everything else ready. So it’s going to be hot and the temperatures are similar and it’s going to work out beautifully. And just the process of how he makes this is amazing. So what we’re about to do, you can’t do unless you have multiple artists doing different parts of the process. Everyone really has a great understanding of the material already, so this is only helping us learn the material better. So when it hits the molten glass, it heats up really quickly and it just kind of melts into the molten glass and it’s not really able to keep its shape.
Cao then takes it out of the furnace, gets the blow pipe and holds it. He puts a little bit of air inside the glass and plugs up the end of the pipe with his finger. The heat from the glass makes the gases expand and does all the work for him, using the ideal gas law to blow up the glass. After that, they have a sphere of glass and then they straighten the edges and make it a cylinder, flattening the end. He then heats it shallow so they can stretch it from the shoulder. He then heats it even shallower, making it upside down with the colder shoulder. He then takes his tongs and pushes down to form the part that’s hotter, using the heat differential to shape it. After that, he heats only the base to flatten and tighten it up again. After that, they put another rod on the other side and break off the cap, turn it around and make the cylinder from the inside out. Once the cup is finished, Cao starts to let everybody know where they need to be because he needs to manage the temperatures and timing. He has a big ladle to get molten glass in and it’s very dangerous. When the Prince Rupert’s drop is put into the molten glass, it heats up quickly and slumps over. So the snapping of the tail has to be done faster because the tail is so skinny. Once Erik shoved the reverse drop into the molten glass, it has to be snapped before the tail keeps up. This is because the Prince Rupert’s drop is solid, but there’s not a lot of mass there and when it hits the molten glass, it heats up quickly and melts into the molten glass, not able to keep its shape. There’s a lot to consider when it comes to working with molten glass, from the heat transfer and heat capacity to the colors one is working with. Karl and his team learned their lesson and made another cup and got ready for another go. This time they used cold water and managed to get the shot. However, they noticed an air bubble had been trapped, and they tried again with a deep blue color, but it didn’t rupture and go down into the molten glass. So, Carl decided to try something different and put it on a punti and put it back in the glory hole. He then used graphite to make a mold and adapted it to his needs so he wouldn’t have to make a cup every time. He also had to practice the cutting for molten enough, and he managed to get one. The first is that glass is an amazing material and there is a tradeoff between how you make a piece.The second is that Karl is a master of his craft and it takes a lot of patience and skill to create these works of art.
After writing an email to Karl Breed, an engineer and an artist, I was able to gain a deeper understanding of glass art. Karl’s art pieces are created in a process that involves a mold, an oven, and the cold shop. In the mold, the glass is heated up and cooled down to relieve internal stresses, and then it is pulled out and examined. In the cold shop, Karl uses a variety of tools such as a lapidary wheel, a super lab, and a diamond wheel to shape and polish the glass pieces. When examined under a Polaris scope, the folds of the glass and the supersonic shock waves that the Prince Rupert Straw created can be seen. From this experience, I learned that glass is an amazing material and that Karl is a master of his craft. It takes a lot of patience and skill to create these works of art. The first thing I learned about was the second order phase transition of glass, which I didn’t know before and found fascinating. Kyle has a unique perspective when it comes to failure, and it was informative to me. He believes that a great piece is balanced right on the edge of failure and success, and it’s exciting to try to find that line. Even though it can be scary to get too close to that line and risk failure, Kyle believes that failure can be a great space for discovery. He is willing to screw up all the way until the finish in order to develop his intuition and vocabulary.
Cal and his team have been able to make a blueprint strop and cast it without melting it, which is incredible. Cal has refused to sell it, but he has agreed to put it up on his website with no price. He also has other pieces, such as clear ones and polarizing filters, that he will be putting up for sale. If you’re interested, you can check out Cal’s website, [Cal Breed dot com](Cal Breed dot com). I wrote an 11-year-old email to Cal offering to tell people about his website and where he’s at so they can commission his work. If you want to support Smarter Every Day, you can do that at [Patreon Ecom slash Smarter Every Day](Patreon Ecom slash Smarter Every Day). Have a great day!