How do 3D Printers work? Science Shorts

0:00Welcome to SquizzKid Science Shorts, the show where we take your big curly questions and unpack the science stories everyone's talking about. Break them down into snack size, science power dances, we sort the fact from the fluff, keep it fun, keep it fast, and whether it's happening in your body, your backyard, or the big wide universe, we're here to explain the science behind the headlines. You've probably printed something before. You press a button, the printer makes a lot of wearing and clonking sounds, and eventually it spits out a flat piece of paper. But imagine pressing print and instead of a piece of paper out came a toy dinosaur, or a shoe, or a piece of rocket engine. Our excellent question this week comes from Ethan, who is eight years old and lives in Kassala in Sydney. He wants to know how do 3D printers work?

1:00Well Ethan, a normal printer uses ink to make a flat or two-dimensional picture. It has height and width but no real depth. A 3D printer makes something with height, width and depth, an object that takes up space and that you can pick up and hold. But before the printer can make anything, it needs a plan. That usually begins with someone creating a 3D model on a computer. They might design something completely new, download an existing design, or use a scanner to copy the shape of a real object. Next, special computer software takes that model and virtually, not in real life, slices it into hundreds or sometimes thousands of extremely thin, flat layers. Imagine slicing a loaf of bread into the thinnest slices imaginable. If you stack every slice back together in the right order, you could rebuild the loaf. A 3D printer does something similar, but instead of slicing an object apart, it builds one up. The most common type of 3D printer starts

2:06with a long strand of plastic called filament. It's wound around a spool. The printer puts the filament into a heated nozzle which melts the plastic and squeezes it out into a very thin line, almost like a tiny computer controlled hot glue gun. The nozzle moves backwards, forwards, inside to side, following the computer's instructions to draw the bottom layer of an object. Then it moves up, the tiniest amount, and adds another layer on top, followed by another, and another, until all those flat layers have become one solid object. And plastic isn't the only thing that can be used as 3D printer ink. Some printers use liquid resin that hardens when light shines on it. Others spread out the layers of metal powder and use a powerful laser to melt exactly the right parts together. There are enormous printers that squeeze out concrete to help construct the walls of houses and third printers that can create shapes from chocolate,

3:09icing, and other squishy ingredients. One of the most useful things about 3D printing is that you can send a digital design almost anywhere. A remote community, a hospital, or a developing country might not have quick access to a tool or a machine part, but if it has the right printer and materials, it could make it right there. Astronauts have even tested 3D printers in space. So if a 3D printer prints another 3D printer, is it the new printer's parent? Is the new one the baby printer? And if they look exactly the same, how would we know which one was which? Ethan, thank you for your wonderful question. Had fun? Follow the show! Drop us a five star review and tell us what you want to know next. Leave your questions in the comments or email me at squizzkidsatthesquizz.com.au and you might just hear your answer right here on next week's Squizz Kids Science Shorts.