This feature won the 2016 Science & Society Writing Award of the Driskill Graduate Program in the Life Sciences (DGP). Written as part of a course bridging scientific issues and public policy, outstanding articles deserving of a wider readership are selected each year for publication in HELIX.
3D printing has become quite the buzzword. If the news is to be believed, it seems that 3D printers should start churning out jetpacks, artificial livers, and assault rifles any day now. However, most of us have never even seen a 3D printer in person. What are these things anyway and what are they good for? More importantly, where’s my jetpack?
3D printing, also known as additive manufacturing, is a process by which solid objects are created by building them up layer by layer. Most common consumer-grade 3D printers accomplish this by extruding a thin stream of plastic through a heated nozzle like a high-precision hot glue gun.
While the basic technology has been around since the 1980’s, the price of these machines has fallen drastically over the past few years. In 2007 the first 3D printer priced at under $10,000 hit the market. Today, there are numerous printer options available for less than $400. These machines are optimized for printing small, solid, plastic parts. This type of printing is ideal for hobbyists who want to make custom knickknacks. Websites like Thingiverse.com provide an enormous array of free and open-source print plans that anyone can download, modify, and print. If you want to print a bust of Yoda or a snazzy set of custom cufflinks the internet has got you covered!
Unfortunately, personal 3D printers are limited in many ways by the strength of the plastic they can print as well as the precision and surface finish they are capable of achieving. If you want to print an item that requires both strength and exact dimensions, like a sturdy wrench to tighten the nuts on your car’s wheel, you might have a difficult time with a home 3D printer.
Still, with machine prices falling, a wide variety of print plans freely available online, and a dedicated maker community constantly remixing and improving ideas, it appears likely that home 3D printing will slowly become more ubiquitous among hobbyists. It remains to be seen whether some future innovation will tip the scales and make 3D printers a staple appliance in every home.
As with any powerful and flexible technology, there are concerns that the widespread availability of personal 3D printing could lead to dangerous unintended consequences for society. In 2013 an organization named Defense Distributed published online plans for 3D printable handgun dubbed the “Liberator”. The Liberator is composed entirely of 3D-printed plastic parts, with the exception of a hardware nail used as a firing pin. This pistol is capable of firing a single round of standard handgun ammunition.
Within days of the plans release, the US State Department ordered them taken down from the web. Defense Distributed complied. However, it has been said that “the internet is forever,” and print files for the Liberator are still widely available on peer-to-peer file sharing sites. I was easily able to obtain a copy of the blueprints while researching this article.
Ultimately though, it seems that the outcry over 3D printed weapons has been hyperbolic. While many hobbyists have produced and tested 3D printed pistols, I was unable to find any reports of a violent crime being committed with a 3D printed gun. Plastic guns like the Liberator are technically difficult produce with consumer-grade printers. They are bulky, only good for a single shot, and libel to explode if built incorrectly.
With actual firearms so readily available to those that want them, 3D printed guns have remained largely a curiosity. However, it does seem prudent for society to begin considering this issue. The ongoing improvement of 3D printing technology is likely to bring increasingly sophisticated weapon production capabilities into the reach of more and more people. The Australian province of New South Wales has gone so far as to make possession of the electronic print files for a gun illegal and punishable with up to 14 years in prison. In the United States, however, the legality of 3D printed guns remains in flux. Lawsuits between Defense Distributed, creators of The Liberator blueprints, and the US State Department are still ongoing, since it is currently legal in the US for anyone to machine their own firearms.
Because of these high-profile lawsuits, most media coverage has focused on at-home 3D printing. The public discourse has largely overlooked the potential uses of 3D printers for industrial applications. Industrial 3D printers can print in a wide variety of materials while maintaining exacting tolerances, avoiding many of the limitations inherent to cheaper personal machines.
While conventional manufacturing methods, such as injection molding, allow for the inexpensive production of millions of items, these methods require the up-front creation of molds which can be both costly and time consuming. 3D printing does not share these set-up barriers. A company that wants to rapidly iterate its product design or produce a limited run of a few hundred items may find it far more economical to produce them via 3D printing. Furthermore, since 3D printing builds items layer-by-layer, complexity comes free. Unlike traditional manufacturing, printing solid blocks of material is no easier than printing items with complex geometries and internal voids. 3D printing allows for the creation of shapes that are simply unattainable by conventional methods.
Major manufacturing companies are already leveraging these advantages. For example, GE Aviation developed a jet fuel injection nozzle for its next-generation LEAP jet engine using 3D printing. A single printed part replaces a conventional nozzle assembled from 21 separately machined parts. The new injector nozzle is 25% lighter and 5-times more durable than the standard part it replaced. This new nozzle is an integral part of GE’s new LEAP engine, which improves fuel efficiency by a staggering 15% over its predecessor. This translates to a fuel-cost savings of more than $1-million dollars per year for every airplane using the new LEAP system.
We have only scratched the surface of what can be crafted with additive manufacturing. 3D printing technology is still in its infancy. Projects are currently underway to 3D print entire buildings, develop conductive filaments for printable circuits, create custom surgical implants to save lives, and even 3D bioprint synthetic liver tissue using a live stem cell ink.
Printer prices are falling, and the underlying technology is evolving rapidly due to increasing demand both from hobbyists and from industry, and legislation has yet to catch up. It is likely that 3D printed items will increasingly become staples in our daily lives. While 3D printing can’t yet build you a jetpack at home, it already helps aircraft companies to build lighter, more fuel-efficient, jet engines to get you there.