What Is 3D Printing And How Exactly Does It Work?
Imagine if you could print out three-dimensional objects straight from a printer in your home. When I was a kid in primary school, I thought it would be awesome if I could print pizzas out of my InkJet. That’s not where I’m heading in this article, but it’s an interesting thought–printing out three-dimensional objects, that is. It sounds like borderline science-fiction, and for a long time, it was. Not anymore.
The process is (not surprisingly) called 3D printing. Like traditional printing, which takes a blank piece of paper and creates two-dimensional images and text out of seemingly nowhere, 3D printing creates fully realized objects out of nothing. It’s a fascinating procedure that can be useful in a number of fields.
Last year, James determined that 3D printing is no longer a myth or farfetched idea. Just in the last 12 months, he’s been proven correct: 3D printing is just getting started. Join me as I explore the ins-and-outs of 3D printing technology to learn how it works and what benefits it could bring to us as consumers.
Brief History of 3D Printing
Back in 1986, a guy named Charles W. Hull filed a patent for stereolithography, which became the first known method of creating 3D objects out of thin air. The invention of this method ushered in a new age of machining processes. Whereas most objects are built using a subtractive process (i.e., whittling, drilling, carving, slicing, etc.), 3D printing uses an additive process (i.e., by adding material).
3D printers are expensive. Traditional paper-and-ink printers will cost you hundreds of dollars, but 3D printers will set you back tens of thousands. Fortunately, you don’t need to own a personal 3D printer since there are already a number of services that will print 3D objects for you. If you’re interested, check out Shapeways and Sculpteo.
Due to the expensive nature of stereolithography, other forms of 3D printing have been pioneered. These newer techniques have their own advantages and disadvantages, but most of them are far cheaper and more accessible to the everyman.
3D Printing Techniques
Stereolithography (SLA) is the first 3D printing technique that was developed. It creates objects out of thin air by printing layers and layers of a particular photopolymer on top of itself. The material begins as a liquid and changes to a solid when hit by a concentrated beam of ultraviolet light.
Digital light processing (DLP) is similar to stereolithography in that it uses light to harden a liquid into a solid. However, in digital light processing, the object starts as a vat of full liquid. A portion of the liquid is exposed to light, which hardens, then the build plate is lowered by a small amount. Another shot of light hardens more of the liquid, and this process repeats. Leftover liquid is drained, leaving behind a solid model.
Selective laser sintering (SLS) uses a high power laser to fuse material particles (e.g., plastic, glass, ceramic, and metal) into a mass that takes the desired three-dimensional shape.
Electron beam melting (EBM) is a 3D printing process used for metal parts. The process takes place in a vacuum and begins by spreading down a layer of metal powder (most often titanium). An electron beam then melts the powder into a solid layer. Objects created this way are surprisingly dense and strong.
Multi jet modeling (MJM) works in a similar manner to modern InkJet printers. It spreads a layer of resin powder and then sprays a colored binding glue-like substance that hardens the powder into a single layer. Multi jet modeling is extremely useful because it is fast and supports colored printing.
Fused deposition modeling (FDM) uses a heated extrusion nozzle that melts a material (e.g., plastic) as it comes out. The nozzle can move around both horizontally and vertically through computer-aided controls. As the material exits the nozzle, it hardens almost immediately.
Nearly all forms of 3D printing require an STL file. An STL file is a specific format of 3D model that allows 3D printers to conveniently and effectively slice up the object into the individual layers used in the actual printing. Most STL files are first created in a computer-aided design (CAD) program and then converted.
Benefits of 3D Printing
3D printers are useful in both a commercial and personal capacity. The only real barrier to personal 3D printing is the extraordinary cost involved and the technical know-how necessary to create working STL models. If you can get over that initial hump, then you’ll see the many benefits.
Design-related work is made much faster and easier with 3D printers. Designers can take concepts and ideas and quickly produce a working three-dimensional representation–called rapid prototyping. As the design evolves over time, each iteration can be prototyped almost immediately.
Companies can also benefit by using 3D printers in creating their final products, not just prototypes. Subtractive processes end up with a lot of wasted materials in the form of shavings, drilling debris, and cut pieces that are too small to be used anywhere. The additive process of 3D printing eliminates most, if not all, forms of waste.
The nature of 3D printing allows for ease of customization. Typical assembly lines require the difference pieces of an object to fit together in a specific way or else the line fails. With a 3D printer, personal customizations are made in the STL file–the printer doesn’t need to be altered.
And the level of detail that can be achieved through 3D printing is phenomenal–unmatched by any other manufacturing method except for objects designed and crafted entirely by hand. The accuracy of a 3D printer can go so far as 4-micron resolution. That’s thinner than a human hair.
3D printing technology is not exactly a world changer, but it’s certainly fascinating and valuable. Companies all over the world already employ 3D printing in their manufacturing processes. Hobbyists already print out singular objects for their own enjoyment. Within the next decade, it’s entirely possible that we’ll see household printers that create 3D objects at our own behest.