How 3D Printers Work

In recent years, 3D printing has been making a name for itself in a variety of different ways. Its popularity has grown from a way to print simple knick-knacks to a way to create rudimentary medical applications. This includes 3D printed hands and partial arms for amputees, all the while taking on the daunting task of printing organic tissue in the hopes of restoring portions of skin, and, maybe one day, internal organs. But the question that has been around for as long as 3D printers themselves: How do they work? 

My friend, Dane Willenborg, walked me through the process, and, as it turns out, they are actually much simpler than one would think. While there are numerous different brands and models, they all work on the same basic ideals. 3D printers “build” on a three-axis platform, thus making them three dimensional. It all begins with the software. Through a multitude of different programs, users can design or download files that they can export to their printers. Exporting programs are the brains of all 3D printers, telling them exactly what parts to move and how to move them to create whatever the desired build is. As soon as the user is satisfied with the digital rendition of their file and with the parameters their printer has been set to, the process begins with heating. While the printer is preparing itself for the job, the point that the material, known as ‘filament,’ exits the machine called the Extruder, or Hot-End, automatically heats itself to the melting point of the filament. Just like there is a variety of different printers, there are even more brands, colors and compositions of filament, all bearing a unique melting point that the user would input to the software they use. Some printers even have a heated bed, which provides better adhesion, so the pieces do not move around during the print, thus ruining what has already been produced. 

As soon as the machine has reached the necessary temperature, the Hot-End moves on its X and Y axis to the starting point of the build. It then travels the shape of the first layer of its build. As the Extruder moves, a gear is pushing filament through the Hot-End causing it to melt, similar to how a hot glue gun melts down its glue sticks. Because the melting point parameters are set so specifically, the melting filament is cooled immediately and hardens to retain the shape it was laid down in. When the Extruder finishes its first layer of the build, it moves very slightly on its Z axis (vertical), where it can then start its second layer. This process repeats itself until the build is completed, which can be hundreds of layers depending on the size and quality of printer. After the print is completed, it is safe to touch, sand, paint, cut, drill holes in, whatever is needed to fulfill the desired outcome. The seemingly unending possibilities of 3D printing could become a prevalent in human history and, after researching, is actually a very simple process.