3D printing or Additive manufacturing is a process of making a three-dimensional solid object of virtually any shape from a digital model. 3D printing is achieved using an additive process, where successive layers of material are laid down in different shapes. 3D printing is also considered distinct from traditional machining techniques, which mostly rely on the removal of material by methods such as cutting or drilling (subtractive processes).
A 3D printer is a limited type of industrial robot that is capable of carrying out an additive process under computer control.
While 3D printing technology has been around since the 1980s, it was not until the early 2010s that the printers became widely available commercially. The first working 3D printer was created in 1984 by Chuck Hull of 3D Systems Corp. Since the start of the 21st century there has been a large growth in the sales of these machines, and their price has dropped substantially. According to Wohlers Associates, a consultancy, the market for 3D printers and services was worth $2.2 billion worldwide in 2012, up 29% from 2011.
The 3D printing technology is used for both prototyping and distributed manufacturing with applications in architecture, construction (AEC), industrial design, automotive, aerospace, military, engineering, civil engineering, dental and medical industries, biotech (human tissue replacement), fashion, footwear, jewelry, eyewear, education, geographic information systems, food, and many other fields. One study has found that open source 3D printing could become a mass market item because domestic 3D printers can offset their capital costs by enabling consumers to avoid costs associated with purchasing common household objects.
The term Additive manufacturing refers to technologies that create objects through sequential layering. Objects that are manufactured additively can be used anywhere throughout the product life cycle, from pre-production (i.e. rapid prototyping) to full-scale production (i.e. rapid manufacturing), in addition to tooling applications and post-production customization.
In manufacturing, and machining in particular, subtractive methods refers to more traditional methods. The term subtractive manufacturing is a retronym developed in recent years to distinguish it from newer additive manufacturing techniques. Although fabrication has included methods that are essentially "additive" for centuries (such as joining plates, sheets, forgings, and rolled work via riveting, screwing, forge welding, or newer kinds of welding), it did not include the information technology component of model-based definition. Machining (generating exact shapes with high precision) has typically been subtractive, from filing and turning to milling, drilling and grinding.
The term stereolithography was defined by Charles W. Hull as a "system for generating three-dimensional objects by creating a cross-sectional pattern of the object to be formed"—in a 1984 patent.
3D Printable Models
3D printable models may be created with a computer aided design package or via 3D scanner. The manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting. 3D scanning is a process of analyzing and collecting data of real object; its shape and appearance and builds digital, three dimensional models.
Both manual and automatic creation of 3D printable models is difficult for average consumers. This is why several 3D Printing Marketplace have emerged over the last years. Among the most popular are Shapeways, Thingiverse and Threeding
To perform a print, the machine reads the design from 3D printable file (STL file) and lays down successive layers of liquid, powder, paper or sheet material to build the model from a series of cross sections. These layers, which correspond to the virtual cross sections from the CAD model, are joined or automatically fused to create the final shape. The primary advantage of this technique is its ability to create almost any shape or geometric feature.
Printer resolution describes layer thickness and X-Y resolution in dpi (dots per inch), or micrometers. Typical layer thickness is around 100 µm (250 DPI), although some machines such as the Objet Connex series and 3D Systems' ProJet series can print layers as thin as 16 µm (1,600 DPI). X-Y resolution is comparable to that of laser printers. The particles (3D dots) are around 50 to 100 µm (510 to 250 DPI) in diameter.
Construction of a model with contemporary methods can take anywhere from several hours to several days, depending on the method used and the size and complexity of the model. Additive systems can typically reduce this time to a few hours, although it varies widely depending on the type of machine used and the size and number of models being produced simultaneously.
Traditional techniques like injection molding can be less expensive for manufacturing polymer products in high quantities, but additive manufacturing can be faster, more flexible and less expensive when producing relatively small quantities of parts. 3D printers give designers and concept development teams the ability to produce parts and concept models using a desktop size printer.
Though the printer-produced resolution is sufficient for many applications, printing a slightly oversized version of the desired object in standard resolution and then removing material with a higher-resolution subtractive process can achieve greater precision.
Some additive manufacturing techniques are capable of using multiple materials in the course of constructing parts. Some are able to print in multiple colors and color combinations simultaneously. Some also utilize supports when building. Supports are removable or dissolvable upon completion of the print, and are used to support overhanging features during construction.
Several different 3D printing processes have been invented since the late 1970s. The printers were originally large, expensive, and highly limited in what they could produce.
A large number of additive processes are now available. They differ in the way layers are deposited to create parts and in the materials that can be used. Some methods melt or soften material to produce the layers, e.g. selective laser melting (SLM) or direct metal laser sintering (DMLS), selective laser sintering (SLS), fused deposition modeling (FDM), while others cure liquid materials using different sophisticated technologies, e.g. stereolithography (SLA). With laminated object manufacturing (LOM), thin layers are cut to shape and joined together (e.g. paper, polymer, metal). Each method has its own advantages and drawbacks, and some companies consequently offer a choice between powder and polymer for the material from which the object is built. Some companies use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, cost of the 3D printer, cost of the printed prototype, and cost and choice of materials and color capabilities.
Printers that work directly with metals are expensive. In some cases, however, less expensive printers can be used to make a mould, which is then used to make metal parts.
- Fused deposition modeling (FDM)
- Thermoplastics (e.g. PLA, ABS)
- Electron Beam Freeform Fabrication (EBF3)
- Direct metal laser sintering (DMLS)
- Electron-beam melting (EBM)
- Selective laser melting (SLM)
- Selective heat sintering (SHS)
- Selective laser sintering (SLS)
- Powder bed and inkjet head 3D printing
- Plaster-based 3D printing (PP)
- Laminated object manufacturing (LOM)
- Stereolithography (SLA)
- Digital Light Processing (DLP)
Main article: Fused deposition modeling
Fused deposition modeling (FDM) was developed by S. Scott Crump in the late 1980s and was commercialized in 1990 by Stratasys. With the expiration of the patent on this technology there is now a large open-source development community, as well as commercial and DIY variants, which utilize this type of 3D printer. This has led to a two orders of magnitude price drop since this technology's creation.
In fused deposition modeling the model or part is produced by extruding small beads of material which harden immediately to form layers. A thermoplastic filament or metal wire that is wound on a coil is unreeled to supply material to an extrusion nozzle head. The nozzle head heats the material and turns the flow on and off. Typically stepper motors or servo motors are employed to move the extrusion head and adjust the flow and the head can be moved in both horizontal and vertical directions. Control of this mechanism is typically done by a computer-aided manufacturing (CAM) software package running on a microcontroller.
Various polymers are used, including acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polylactic acid (PLA), high density polyethylene (HDPE), PC/ABS, and polyphenylsulfone (PPSU). In general the polymer is in the form of a filament, fabricated from virgin resins. Multiple projects in the open-source community exist that are aimed at processing post-consumer plastic waste into filament. These involve machines to shred and extrude the plastic material into filament.
FDM has some restrictions on the shapes that may be fabricated. For example, FDM usually cannot produce stalactite-like structures, since they would be unsupported during the build. These have to be avoided or a thin support may be designed into the structure which can be broken away during finishing.
The CandyFab granular printing system uses heated air and granulated sugar to produce food-grade art objects.
Another 3D printing approach is the selective fusing of materials in a granular bed. The technique fuses parts of the layer, and then moves the working area downwards, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece. A laser is typically used to sinter the media into a solid. Examples include selective laser sintering (SLS), with both metals and polymers (e.g. PA, PA-GF, Rigid GF, PEEK, PS, Alumide, Carbonmide, elastomers), and direct metal laser sintering (DMLS).
Selective Laser Sintering (SLS) was developed and patented by Dr. Carl Deckard and Dr. Joseph Beaman at the University of Texas at Austin in the mid-1980s, under sponsorship of DARPA. A similar process was patented without being commercialized by R. F. Housholder in 1979.
Selective Laser Melting (SLM) does not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layerwise method with similar mechanical properties to conventional manufactured metals.
Electron beam melting (EBM) is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum. Unlike metal sintering techniques that operate below melting point, EBM parts are fully dense, void-free, and very strong.
Another method consists of an inkjet 3D printing system. The printer creates the model one layer at a time by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. This is repeated until every layer has been printed. This technology allows the printing of full color prototypes, overhangs, and elastomer parts. The strength of bonded powder prints can be enhanced with wax or thermoset polymer impregnation.
In some printers, paper can be used as the build material, resulting in a lower cost to print. During the 1990s some companies marketed printers that cut cross sections out of special adhesive coated paper using a carbon dioxide laser, and then laminated them together.
In 2005, Mcor Technologies Ltd developed a different process using ordinary sheets of office paper, a Tungsten carbide blade to cut the shape, and selective deposition of adhesive and pressure to bond the prototype.
There are also a number of companies selling printers that print laminated objects using thin plastic and metal sheets.
Stereolithography was patented in 1986 by Chuck Hull. Photopolymerization is primarily used in stereolithography (SLA) to produce a solid part from a liquid. This process dramatically redefined previous efforts, from the Photosculpture method of François Willème (1830–1905) in 1860 through the photopolymerization of Mitsubishi`s Matsubara in 1974.
In Digital Light Processing (DLP), a vat of liquid polymer is exposed to light from a DLP projector under safelight conditions. The exposed liquid polymer hardens. The build plate then moves down in small increments and the liquid polymer is again exposed to light. The process repeats until the model has been built. The liquid polymer is then drained from the vat, leaving the solid model. The EnvisionTEC Perfactory is an example of a DLP rapid prototyping system.
Inkjet printer systems like the Objet PolyJet system spray photopolymer materials onto a build tray in ultra-thin layers (between 16 and 30 µm) until the part is completed. Each photopolymer layer is cured with UV light after it is jetted, producing fully cured models that can be handled and used immediately, without post-curing. The gel-like support material, which is designed to support complicated geometries, is removed by hand and water jetting. It is also suitable for elastomers.
Ultra-small features can be made with the 3D microfabrication technique used in multiphoton photopolymerization. This approach traces the desired 3D object in a block of gel using a focused laser. Due to the nonlinear nature of photoexcitation, the gel is cured to a solid only in the places where the laser was focused and the remaining gel is then washed away. Feature sizes of under 100 nm are easily produced, as well as complex structures with moving and interlocked parts.
Yet another approach uses a synthetic resin that is solidified using LEDs.
In this technique a 3D digital model is sliced by a set of horizontal planes. Each slice is converted into a two-dimensional mask image. The mask image is then projected onto a photocurable liquid resin surface and light is projected onto the resin to cure it in the shape of the layer.
In research systems, the light is projected from below, allowing the resin to be quickly spread into uniform thin layers, reducing production time from hours to minutes.
The technique has been used to create objects composed of multiple materials that cure at different rates.
Commercially available devices such as Objet Connex apply the resin via small nozzles.
3D Printers - Industry use
As of October 2012, Stratasys, the result of a merger of an American and an Israeli company, now sells additive manufacturing systems that range from $2,000 to $500,000; General Electric uses the high-end model to build parts for turbines, one example of GE's commitment of in-house investment of more than $1 billion on the technology.
Airwolf 3D AW3D v.4 (Prusa).
Several projects and companies are making efforts to develop affordable 3D printers for home desktop use. Much of this work has been driven by and targeted at DIY/enthusiast/early adopter communities, with additional ties to the academic and hacker communities.
RepRap is one of the longest running projects in the desktop category. The RepRap project aims to produce a free and open source hardware (FOSH) 3D printer, whose full specifications are released under the GNU General Public License, and which is capable of replicating itself by printing many of its own (plastic) parts to create more machines. RepRaps have already been shown to be able to print circuit boards and metal parts.
Because of the FOSH aims of RepRap, many related projects have used their design for inspiration, creating an ecosystem of related or derivative 3D printers, most of which are also open source designs. The availability of these open source designs means that variants of 3D printers are easy to invent. The quality and complexity of printer designs, however, as well as the quality of kit or finished products, varies greatly from project to project. This rapid development of open source 3D printers is gaining interest in many spheres as it enables hyper-customization and the use of public domain designs to fabricate open source appropriate technology through conduits such as Thingiverse and Cubify. This technology can also assist initiatives in sustainable development since technologies are easily and economically made from resources available to local communities.
The cost of 3D printers has decreased dramatically since about 2010, with machines that used to cost $20,000 costing less than $1,000. For instance, as of 2013, several companies and individuals are selling parts to build various RepRap designs, with prices starting at about €400 / US$500. The open source [email protected] project has developed printers for general use with anything that can be squirted through a nozzle, from chocolate to silicone sealant and chemical reactants. Printers following the project's designs have been available from suppliers in kits or in pre-assembled form since 2012 at prices in the US$2000 range. The Kickstarter funded Peachy Printer is designed to cost $100 and several other new 3D printers are aimed at the small, inexpensive market including the mUVe3D and Lumifold. Professional grade 3D-printer crowdsourced costing $1499 is designed by Rapide 3D and has no fumes nor constant rattle during use. The 3D Doodler, "3D printing pen", raised USD 2.3 million on Kickstarter with the pens selling at USD 99. Though the 3D Doodler has been criticized for being more of a crafting pen than a 3D printer.
As the costs of 3D printers have come down they are becoming more appealing financially to use for self-manufacturing of personal products. In addition, 3D printing products at home may reduce the environmental impacts of manufacturing by reducing material use and distribution impacts.
In addition, several RecycleBots such as the commercialized Filastrucer have been designed and fabricated to convert waste plastic, such as shampoo containers and milk jugs, into inexpensive RepRap filament. There is some evidence that using this approach of distributed recycling is better for the environment.
The development and hyper-customization of the RepRap-based 3D printers has produced a new category of printers suitable for small business and consumer use. Manufacturers such as Solidoodle, RoBo, and RepRapPro have introduced models and kits priced at less than $1,000, thousands less than they were in September 2012. Depending on the application, the print resolution and speed of manufacturing lies somewhere between a personal printer and an industrial printer. A list of printers with pricing and other information is maintained. Most recently delta robots, like the TripodMaker, have been utilized for 3D printing to increase fabrication speed further. For delta 3D printers, due to its geometry and differentiation movements, the accuracy of the print depends on the position of the printer head.
Some companies are also offering software for 3D printing, as a support for hardware manufactured by other companies.
Three-dimensional printing makes it as cheap to create single items as it is to produce thousands and thus undermines economies of scale. It may have as profound an impact on the world as the coming of the factory did....Just as nobody could have predicted the impact of the steam engine in 1750—or the printing press in 1450, or the transistor in 1950—it is impossible to foresee the long-term impact of 3D printing. But the technology is coming, and it is likely to disrupt every field it touches.
The Economist, in a February 10, 2011 leader
An example of 3D printed limited edition jewellery. This necklace is made of glassfiber-filled dyed nylon. It has rotating linkages that were produced in the same manufacturing step as the other parts.
Additive manufacturing's earliest applications have been on the toolroom end of the manufacturing spectrum. For example, rapid prototyping was one of the earliest additive variants, and its mission was to reduce the lead time and cost of developing prototypes of new parts and devices, which was earlier only done with subtractive toolroom methods (typically slowly and expensively). With technological advances in additive manufacturing, however, and the dissemination of those advances into the business world, additive methods are moving ever further into the production end of manufacturing in creative and sometimes unexpected ways. Parts that were formerly the sole province of subtractive methods can now in some cases be made more profitably via additive ones.
Standard applications include design visualization, prototyping/CAD, metal casting, architecture, education, geospatial, healthcare, and entertainment/retail.
Industrial 3D printers have existed since the early 1980s and have been used extensively for rapid prototyping and research purposes. These are generally larger machines that use proprietary powdered metals, casting media (e.g. sand), plastics, paper or cartridges, and are used for rapid prototyping by universities and commercial companies.
Advances in RP technology have introduced materials that are appropriate for final manufacture, which has in turn introduced the possibility of directly manufacturing finished components. One advantage of 3D printing for rapid manufacturing lies in the relatively inexpensive production of small numbers of parts.
Rapid manufacturing is a new method of manufacturing and many of its processes remain unproven. 3D printing is now entering the field of rapid manufacturing and was identified as a "next level" technology by many experts in a 2009 report. One of the most promising processes looks to be the adaptation of selective laser sintering (SLS), or direct metal laser sintering (DMLS) some of the better-established rapid prototyping methods. As of 2006, however, these techniques were still very much in their infancy, with many obstacles to be overcome before RM could be considered a realistic manufacturing method.
Companies have created services where consumers can customize objects using simplified web based customization software, and order the resulting items as 3D printed unique objects. This now allows consumers to create custom cases for their mobile phones. Nokia has released the 3D designs for its case so that owners can customize their own case and have it 3D printed.
The current slow print speed of 3D printers limits their use for mass production. To reduce this overhead, several fused filament machines now offer multiple extruder heads. These can be used to print in multiple colors, with different polymers, or to make multiple prints simultaneously. This increases their overall print speed during multiple instance production, while requiring less capital cost than duplicate machines since they can share a single controller.
Distinct from the use of multiple machines, multi-material machines are restricted to making identical copies of the same part, but can offer multi-color and multi-material features when needed. The print speed increases proportionately to the number of heads. Furthermore, the energy cost is reduced due to the fact that they share the same heated print volume. Together, these two features reduce overhead costs.
Many printers now offer twin print heads. However, these are used to manufacture single (sets of) parts in multiple colors/materials.
Few studies have yet been done in this field to see if conventional subtractive methods are comparable to additive methods.
As of 2012, domestic 3D printing has mainly captivated hobbyists and enthusiasts and has not quite gained recognition for practical household applications. A working clock has been made and gears have been printed for home woodworking machines among other purposes. 3D printing is also used for ornamental objects. Web sites associated with home 3D printing tend to include backscratchers, coathooks, doorknobs etc.
As of 2013, 3D printers have been used to help animals. A 3D printed foot let a crippled duckling walk again. 3D printed stylish hermit crab shells let them inhabit a new style home. Printers have also made decorative pieces for humans such as necklaces, rings, bags etc.
The open source [email protected] project has developed printers for general use. They have been used in research environments to produce chemical compounds with 3D printing technology, including new ones, initially without immediate application as proof of principle. The printer can print with anything that can be dispensed from a syringe as liquid or paste. The developers of the chemical application envisage that this technology could be used for both industrial and domestic use. Including, for example, enabling users in remote locations to be able to produce their own medicine or household chemicals. The OpenReflex analog SLR camera was developed for 3D printing as an open source student project.
3D printing has spread into the world of clothing with fashion designers experimenting with 3D-printed bikinis, shoes, and dresses. In commercial production Nike is using 3D printing to prototype and manufacture the 2012 Vapor Laser Talon football shoe for players of American football, and New Balance is 3D manufacturing custom-fit shoes for athletes.
As of 2012, 3D bio-printing technology has been studied by biotechnology firms and academia for possible use in tissue engineering applications in which organs and body parts are built using inkjet techniques. In this process, layers of living cells are deposited onto a gel medium or sugar matrix and slowly built up to form three-dimensional structures including vascular systems. The first production system for 3D tissue printing, was delivered in 2009, based on NovoGen bioprinting technology. Several terms have been used to refer to this field of research: organ printing, bio-printing, body part printing, and computer-aided tissue engineering, among others.
An early-stage medical laboratory and research company, called Organovo, designs and develops functional, three dimensional human tissue for medical research and therapeutic applications. The company utilizes its NovoGen MMX Bioprinter for 3D bioprinting. Organovo anticipates that the bioprinting of human tissues will accelerate the preclinical drug testing and discovery process, enabling treatments to be created more quickly and at lower cost. Additionally, Organovo has long-term expectations that this technology could be suitable for surgical therapy and transplantation.
3D printing for implant and medical device
3D printing has been used to print patient specific implant and device for medical use. Successful operations include a titanium pelvic implanted into a British patient, titanium lower jaw transplanted to a Dutch patient and a plastic tracheal splint for an American infant. The hearing aid and dental industries are expected to be the biggest area of future development using the custom 3D printing technology. In March 2014, surgeons in Swansea used 3D printed parts to rebuild the face of a motorcyclist who had been seriously injured in a road accident.
3D printing services
Some companies offer on-line 3D printing services open to both consumers and industries. Such services require people to upload their 3D designs to the company website. Designs are then 3D printed using industrial 3D printers and either shipped to the customer or in some cases, the consumer can pick the object up at the store.
Research into new applications
Future applications for 3D printing might include creating open-source scientific equipment to create open source labs or other science-based applications like reconstructing fossils in paleontology, replicating ancient and priceless artifacts in archaeology, reconstructing bones and body parts in forensic pathology, and reconstructing heavily damaged evidence acquired from crime scene investigations. The technology currently being researched for building construction.
In 2005, academic journals had begun to report on the possible artistic applications of 3D printing technology. By 2007 the mass media followed with an article in the Wall Street Journal and Time Magazine, listing a 3D printed design among their 100 most influential designs of the year. During the 2011 London Design Festival, an installation, curated by Murray Moss and focused on 3D Printing, was held in the Victoria and Albert Museum (the V&A). The installation was called Industrial Revolution 2.0: How the Material World will Newly Materialize.
A proof-of-principle project at the University of Glasgow, UK, in 2012 showed that it is possible to use 3D printing techniques to create chemical compounds, including new ones. They first printed chemical reaction vessels, then used the printer to squirt reactants into them as "chemical inks" which would then react. They have produced new compounds to verify the validity of the process, but have not pursued anything with a particular application. Cornell Creative Machines Lab has confirmed that it is possible to produce customized food with 3D Hydrocolloid Printing. Professor Leroy Cronin of Glasgow University proposed, in a TED Talk that it should one day be possible to use chemical inks to print medicine.
The use of 3D scanning technologies allows the replication of real objects without the use of moulding techniques that in many cases can be more expensive, more difficult, or too invasive to be performed, particularly for precious or delicate cultural heritage artifacts where direct contact with the molding substances could harm the original object's surface.
An additional use being developed is building printing, or using 3D printing to build buildings. This could allow faster construction for lower costs, and has been investigated for construction of off-Earth habitats. For example, the Sinterhab project is researching a lunar base constructed by 3D printing using lunar regolith as a base material. Instead of adding a binding agent to the regolith, researchers are experimenting with microwave sintering to create solid blocks from the raw material.
Employing additive layer technology offered by 3D printing, Terahertz devices which act as waveguides, couplers and bends have been created. The complex shape of these devices could not be achieved using conventional fabrication techniques. Commercially available professional grade printer EDEN 260V was used to create structures with minimum feature size of 100 µm. The printed structures were later DC sputter coated with gold (or any other metal) to create a Terahertz Plasmonic Device.
China has committed almost $500 million towards the establishment of 10 national 3-D printing development institutes. In 2013, Chinese scientists began printing ears, livers and kidneys, with living tissue. Researchers in China have been able to successfully print human organs using specialized 3D bio printers that use living cells instead of plastic. Researchers at Hangzhou Dianzi University actually went as far as inventing their own 3D printer for the complex task, dubbed the “Regenovo” which is a "3D bio printer." Xu Mingen, Regenovo's developer, said that it takes the printer under an hour to produce either a mini liver sample or a four to five inch ear cartilage sample. Xu also predicted that fully functional printed organs may be possible within the next ten to twenty years. In the same year, researchers at the University of Hasselt, in Belgium had successfully printed a new jawbone for an 83-year-old Belgian woman. The woman is now able to chew, speak and breathe normally again after a machine printed her a new jawbone.
In Bahrain, large-scale 3D printing using a sandstone-like material has been used to create unique coral-shaped structures, which encourage coral polyps to colonize and regenerate damaged reefs. These structures have a much more natural shape than other structures used to create artificial reefs, and have a neutral pH which concrete does not.
Some of the recent developments in 3D printing were revealed at the 3DPrintshow in London, which took place in November 2013 and 2014. The art section had in exposition artworks made with 3D printed plastic and metal. Several artists such as Joshua Harker, Davide Prete, Sophie Kahn, Helena Lukasova, Foteini Setaki showed how 3D printing can modify aesthetic and art processes. One part of the show focused on ways in which 3D printing can advance the medical field. The underlying theme of these advances was that these printers can be used to create parts that are printed with specifications to meet each individual. This makes the process safer and more efficient. One of these advances is the use of 3D printers to produce casts that are created to mimic the bones that they are supporting. These custom-fitted casts are open, which allow the wearer to scratch any itches and also wash the damaged area. Being open also allows for open ventilation. One of the best features is that they can be recycled to create more casts. In December 2013, BAE Systems fitted and successfully test flew a Panavia Tornado with parts made by 3D printing.
As early as 2010, work began on applications of 3D printing in zero or low gravity environments. The primary concept involves creating basic items such as hand tools or other more complicated devices "on demand" versus using valuable resources such as fuel or cargo space to carry the items into space.
Additionally, NASA is conducting tests with company Made in Space to assess the potential of 3D printing to make space exploration cheaper and more efficient. Rocket parts built using this technology have passed NASA firing tests. In July 2013, two rocket engine injectors performed as well as traditionally constructed parts during hot-fire tests which exposed them to temperatures approaching 6,000 degrees Fahrenheit (3,316 degrees Celsius) and extreme pressures. NASA is also preparing to launch a 3D printer into space; the agency hopes to demonstrate that, with the printer making spare parts on the fly, astronauts need not carry large loads of spares with them.
Since the 1950s, a number of writers and social commentators have speculated in some depth about the social and cultural changes that might result from the advent of commercially-affordable additive manufacturing technology. Amongst the more notable ideas to have emerged from these inquiries has been the suggestion that, as more and more 3D printers start to enter people's homes, so the conventional relationship between the home and the workplace might get further eroded. Likewise, it has also been suggested that, as it becomes easier for businesses to transmit designs for new objects around the globe, so the need for high-speed freight services might also become less. Finally, given the ease with which certain objects can now be replicated, it remains to be seen whether changes will be made to current copyright legislation so as to protect intellectual property rights with the new technology widely available.
In 2012, the U.S.-based group Defense Distributed disclosed plans to " a working plastic gun that could be downloaded and reproduced by anybody with a 3D printer." Defense Distributed has also designed a 3D printable AR-15 type rifle lower receiver (capable of lasting more than 650 rounds) and a 30 round M16 magazine. Soon after Defense Distributed succeeded in designing the first working blueprint to produce a plastic gun with a 3D printer in May 2013, the United States Department of State demanded that they remove the instructions from their website.
After Defense Distributed released their plans, questions were raised regarding the effects that 3D printing and widespread consumer-level CNC machining may have on gun control effectiveness.