We have heard of 3D printing from newscasters and journalists, astonished at what they’ve witnessed. A machine reminiscent of the Star Trek Replicator, something magical that can create objects out of thin air. It can “print” in plastic, metal, nylon, and over a hundred other materials. It can be used for making nonsensical little models like the over-printed Yoda, yet it can also print manufacturing prototypes, end user products, quasi-legal guns, aircraft engine parts and even human organs using a person’s own cells.
3D printers use a variety of very different types of additive manufacturing technologies, but they all share one core thing in common: they create a three dimensional object by building it layer by successive layer, until the entire object is complete. It’s much like printing in two dimensions on a sheet of paper, but with an added third dimension: UP. The Z-axis.
Each of these printed layers is a thinly-sliced, horizontal cross-section of the eventual object. Imagine a multi-layer cake, with the baker laying down each layer one at a time until the entire cake is formed. 3D printing is somewhat similar, but just a bit more precise than 3D baking.
Stick with us and we’ll go through the various types of additive manufacturing. From FDM printing, where a material is melted and extruded in layers, one upon the other, to SLS printing, where a bed of powder material such as nylon or titanium is “sintered” (hardened) layer upon thin layer within it until a model is pulled out of it. It’s a fascinating and quickly advancing world that will change our lives as we know it.
It Begins with a Digital File
autodesk 123d 3D printingIn the 2D world, a sheet of printed paper output from a printer was “designed” on the computer in a program such as Microsoft Word. The file — the Word document — contains the instructions that tell the printer what to do.
In the 3D world, a 3D printer also needs to have instructions for what to print. It needs a file as well. The file — a Computer Aided Design (CAD) file — is created with the use of a 3D modeling program, either from scratch or beginning with a 3D model created by a 3D scanner. Either way, the program creates a file that is sent to the 3D printer. Along the way, software slices the design into hundreds, or more likely thousands, of horizontal layers. These layers will be printed one atop the other until the 3D object is done.
The term 3D printing is the common term for the correct manufacturing term of “additive manufacturing.” But 3D printing will remain the term of choice as who really is going to run around saying things like, “I’m going to go additively manufacture a new iPhone case.” No, they are going to “3D print” it. It just sounds so much cooler too, doesn’t it?