The vast majority of people are just now learning about the existence of 3D printers, but the first of these machines was actually created in 1984 by Charles Hull, co-founder of 3D Systems. These machines work by a process called stereolithography, in which tangible, three-dimensional objects are created from digital data. The first documented use of stereolithography was in 1981 by Hideo Kodama of Nagoya Municipal Industrial Research Institute. From the earliest prototypes, these machines have evolved to the point that, today, electronic scanners are able to take full, three-dimensional scans of real-world objects and have the printer
reproduce them in plastic, down to the finest detail.
3D printers work a lot like the more familiar inkjet printer. However, instead of placing droplets of ink on paper media, these printers liquify a polymer and lay that substance down in multiple layers until the accretion results in a fully three-dimensional object. Using virtual blueprints, usually created with the help of a 3D scanner, the printer software then breaks these blueprints down into individual “slices”, almost similar to an MRI, which are then printed successively until all of the slices have been printed on top of one another to create the full 3D object. Ultimately, the final object is created piecemeal by the printing of numerous cross-sections.
There are various ways in which different 3D printers apply their particular medium in the process of creating a fully three-dimensional object. Some printers melt or soften a solid medium in order to use it in printing, while others “cure” liquid materials. Stereolithography, mentioned previously, is an example of the latter, while Selective Laser Melting is an example of the former. There have been several other processes developed over the past few decades, all using different methods to create the same result.
Initially, these printers were used mainly to create plastic prototypes of new products in various industries, but over time the scope of applications has evolved into a wide variety of uses. The most well-known and well-publicized (and controversial) example as of late has been the creation of usable, fully-functioning 3D guns by Defense Distributed, a Texas company headed by Cody Wilson. After using the crowd-funding site Indiegogo to raise the capital necessary to create a 3D printed gun, Wilson accumulated over $20,000 for the project. However, Indiegogo determined that Wilson's proposal had violated the website's terms of service, and canceled the project and refunded all of the donated money. Undeterred, Wilson continued the crowd-sourcing effort on his own website and quickly regained all of the lost money.
Most controversial about Defense Distributed's products are the fact that they are known as “wiki guns”, meaning that the blueprints are available for free online, and anyone with access to a 3D printer can potentially use those schematics to build their working, plastic firearm. In addition to the common dangers of firearms in general, these items are even more controversial due to the fact that they can escape detection by conventional metal detectors. The implications for safety and security are vast.
However, there are many other extraordinary uses for 3D printer technology which have not been equally publicized. 3D Systems actually created 3D printed organic scaffolding for organ transplants in the late 90s. In addition to applications in the medical, industrial, and firearms fields, 3D printing will soon be invaluable to fields such as archaeology and paleontology, in which scholars hope to someday use this technology to scan and reproduce copies of precious artifacts and fossils. The myrid possibilities for future applications make the field of 3D printing a highly interesting and rapidly-evolving one.