At its core, 3D printing is about using 3D printers, software and specific materials to convert a digital project from a computer file into a physical object that you can hold in your hand, but the reality is that this technology is capable of so much more. In fact, some experts, like economic and social theorist Jeremy Rifkin, have predicted that advances in 3D printing likely heralds the start of a third industrial revolution through the digitization of manufacturing. If you do research online, sources like Wikipedia can provide the history of 3D printing, which also is known as additive manufacturing. It’s a process that creates a three-dimensional object from layers of material formed through computer control. These objects can be almost any shape or design, and they are produced from digital model data, including CAD (computer-aided design) and AMF (additive manufacturing) files. As terminology, ‘3D printing’ originally referred to a much different process where binder material was deposited onto a powder bed by inkjet printer heads in successive layers. In recent years, 3D printing has become synonymous with additive manufacturing techniques.
There are currently seven categories of additive manufacturing processes: Binder jetting, directed energy deposition, material extrusion, material jetting, powder bed fusion, sheet lamination and vat photopolymerization. Early additive manufacturing equipment was developed in the 1980s, including advances perfected by Hideo Kodama of the Nagoya Municipal Industrial Research Institute whereby a three-dimensional plastic model was fabricated with photo-hardening thermoset polymer where the UV-exposure area was controlled by a mask pattern or the scanning fiber transmitter. Three-dimensional models can be printed from an STL (Stereolithography) file, but users must first examine the file for errors, such as holes, self-intersections and manifold errors. Such issues are more common in STL files that have been produced from a model obtained through 3D scanning. The STL file is then processed by a “slicer,” which is software that converts the model into a series of thin layers to produce a G-code file, which contains instructions specific to certain 3D printers. These G-code files can be printed with 3D printing software that instructs the printer throughout the design. Each 3D printer has its own resolution, which describes both the layer thickness and X-Y resolution in dots-per-inch (dpi) or micrometers. The standard layer thickness is about 250 dpi, although some 3D printers can print layers as thin as 1,600 dpi. The X-Y resolution is comparable to a traditional laser printer, with 3D dots, or particles, about 510 dpi to 250 dpi in diameter.
Constructing a 3D model using contemporary methods can take a few hours to a few days, depending on the printing method employed and the size and complexity of the item being designed. Additive manufacturing systems often can reduce the time expended to as little as a few hours, but that can vary depending on the 3D printer being used and the number of items being produced at one time. More traditional techniques, such as injection molding, can be less expensive when manufacturing a large number of polymer products, but additive manufacturing processes can be faster, less expensive and more flexible for smaller production runs. With 3D printers now priced more affordably, designers and development teams can easily produce parts and prototype models using a standard, desktop-sized 3D printer. Regardless of the 3D printer being used, it still requires material to create an object. The most common materials used with 3D printers are PLA, or polylactic acid, which is a biodegradable thermoplastic filament that provides toughness to 3D-printed objects so they aren’t easily damaged, and ABS, or acrylonitrile butadiene styrene, another thermoplastic that provides resistance to UV rays and other corrosive elements. However, recently, new and different materials have emerged as being compatible with 3D printing. Some companies are now recycling waste from coffee, beer and hemp to mix with plastics to produce a new type of filament that is both durable and textured. And stronger materials such as onyx, carbon fiber and even Kevlar are being used to manufacture larger-scale 3D projects that need to be durable, impact-resistant and strong enough to sustain weight and use.