3D Printing

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MOD-t printer by New Matter

3D printing is the process of creating a three-dimensional object via additive manufacturing, a process where 2D layers are printed atop one another until the object is finally complete.[1] Because it allows for an input of a large variety of materials, 3D printing is extremely flexible and allows for highly customized products to be created.


3D Modelling

Example of a 3D Model

A 3D model is a mathematical representation of a 3D object on the computer that acts as the “instructions" that a 3D printer reads from. A large collection of such models are freely available in many online communities such as TF3DM, TurboSquid, and GrabCAD.


The two primary methods in 3D modelling include computer-aided design (CAD) and 3D scanning:

  • Computer-aided design (CAD) - Using software such as AutoCAD, Blender, Google Sketchup, and Maya, models can be drafted out on the computer by hand.
  • 3D Scanning - Using a 3D scanner allows for the quick capture of the physical measurements of any object.[2] Depending on how accurate the scanner is, the model may need to be manually polished afterwards. The big downside is that the object that you wish to have a 3D model of must already exist in the real world, making this method not useful for innovations.


Shell and Solid Model

There are two primary types of 3D models:

  • Shell – Also known as boundary models, shell models focus on showcasing a shell of the object and how it visually looks. It is commonly used for general animation and games.
  • Solid – Solid models not only show how an object appears but also takes into consideration the volume and physical properties of the object, such as its weight, flexibility, and resilience. This type of model has applications primarily in the engineering and architecture industry.


Unlike a regular printer that can only use ink or toner, 3D printers as a whole accept a large variety of materials such as plastics, metals, ceramics, and even molecules. In consumer use, the most commonly used materials are acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) plastics.[3]

Current Status/Position

Gartner's 2013 Hype Cycle for Emerging Technologies

Gartner's Hype Cycle of Emerging Technologies 2013

Several 3D printing-related topics make appearances in the Gartner 2013 Hype Cycle for Emerging Technologies.[4] 3D Bioprinting, consumer 3D printing as well as 3D scanners are all still infantile and are expected to be developed for the next five to ten years. Enterprise 3D printing, however, has been in development for longer and is expected to reach mainstream acceptance within the next two to five years.

Gartner 2014 Top 10 Strategic Technology Trends

3D Printing has also been ranked by Gartner as the tenth top technology trend to pay attention to in the coming year. Although it was initially astronomically-priced (i.e. $25,000), consumer-grade 3D printing is becoming affordable to the average consumer and shipments of 3D printers are expected to increase by 75% in 2014. This number is expected to double in 2015 as well.[5]


  • 1984 - Charles Hull invented stereolithography (SLA), a printing process allowing users to create 3D objects from digital data.[6]
  • 1986 - Hull patented SLA and established the company 3D Systems.[6]
  • 1986 - Hull developed the .STL format standard that is accepted by design software for the printing of 3D objects. 3D Systems continued to grow and eventually developed the first 3D printer, which was known at the time as stereolithography apparatus.[6]
  • 1989 - S. Scott Crump and Lisa Crump, the cofounders of Stratasys, invented and patented the fused deposition modeling (FDM) technology. This technology enabled machines to print 3D objects layer by layer.[6]
  • 1992 - The world's first commercial 3D printer, the SLA-250, became available.[6]
  • 1993 - Professor Michael Cima and Emanuel Sachs from MIT invented and patented a new 3D printing technique, which is what we now know as 3D printing, that allowed users to print plastic, metal, and ceramic parts.[6]
  • 2002 - Wake Forest Institute for Regenerative Medicine 3D printed a miniature functional kidney with the ability to filter blood.[7]
  • 2006 - The first selective laser sintering machine became viable. The machine uses a laser to fuse materials into 3D products.[7]
  • 2006 - 3D printing systems and material provider Objet launched Objet Connex, the first 3D printer that could print an object with multiple materials, including elastomers and polymers.[7]
  • 2007 - RepRap, an open-source project founded by Dr. Adrian Bowyer at University of Bath released Darwin, the first self-replicating printer, which was able to print a majority of its own parts.[7]
  • 2008 - Bespoke Innovations, a manufacturer of prosthetic devices, made a major breakthrough by printing a prosthetic leg with all parts combined in the same structure as a real leg.[7]
  • 2009 - Organovo Holdings Inc., the bioprinting innovator founded in 2007, was able to print the first blood vessel using a 3D bioprinter.[7]
  • 2011 - The world's first 3D printed robotic aircraft was created.[7]
  • 2011 - The world's first 3D printed car was created.[7]
  • 2012 - A 3D printed prosthetic jaw was implemented into an 83-year-old woman suffering from a chronic bone infection.[7]
  • 2013 - The first 3D printed gun was created by Defense Distributed.[7]

Enterprise Printing

With the ability to custom-design and produce in large quantities, 3D printing can be used in many different ways. The following four industries have had major breakthroughs due to recent improvements in 3D printing technology:


Organovo Company Profile

Bioprinting refers to the use of a specialized 3D printer to create human tissues. Organovo is a company that is highly engaged in developing and commercializing 3D printed human tissues that can be used in drug discovery and development, biological research, and implementation of tissues and organs for treatment purposes. To achieve its goals, it relies on the NovoGen MMX Bioprinter (NovoGen). NovoGen is an automated multiple three-dimensional (3D) bioprinter allowing Organovo to print 3D living tissues, including mammalian cells.[1]

The process of bioprinting is complex and involves many different steps. Modified cartridges and extracted cells are the “ink" of bioprinting. Cancer and stem cells are sourced from patient biopsies. They are then put into a growth medium in Petri dishes which would allow them to multiply. When enough cells are grown, they are collected and loaded into a cartridge and the finished product is called Bioink. A NovoGen printer utilizes both Bioink and Hydrogel, which is a type of synthetic matrix that is used as a scaffold for building 3D layers of cells. During the processes of bioprinting, the machine would first print a layer of Hydrogel, which is then followed by a layer of Bioink cells, and so on. The layers naturally fuse together, and once they are all printed, the tissue is left to mature and grow and during this time the Hydrogel is removed.[2]

Currently, the technology of bioprinting is most often used in the following areas:

Drug Discovery and Development

Drug discovery is a very expensive process with a high rate of failure. Furthermore, different species can react to drugs in multiple ways, which makes the process even more difficult. However, after the development of 3D printed tissues, the process of drug discovery has become more reliable. The reduction in complications, along with lower costs, contribute to a shorter drug discovery process timescale.[3]

Drug Testing

In 2013, the European Union (EU) established a new legislation banning the use of animal testing for personal consumer products. This led to companies in the EU looking for new alternatives. 3D printed cells provide for the needs of these companies, especially for the cosmetic industry which represents the single largest market in the EU. For example, in October 2013, L'Oreal entered into an agreement with Organovo to explore the use of 3D bioprinting for safety tests.[3] 3D printed tissue samples are also perfect to test drugs and other medical advancements. Instead of using human beings or animals as pharmaceutical test subjects, bioprinting may provide a much more cost-effective and ethical option.[3]

Tissue Implants

The ultimate goal of bioprinting is to be able to print a full-sized, functional organ which can be implanted into the human body. Although the ability to print fully functional organs has not yet been achieved, there are certain body parts that have been printed and implanted into patients. Two year old Hannah Warren was born without a trachea. A substitute windpipe was required to keep her alive, which was created from plastic fibers and a stew of her own stem cells using a bioprinter.[4] In Argentina, 125mm x 100mm of 3D printed titanium material was implanted into a patient who had suffered a large skull fracture.[5]


3D Printed House

The very first attempt of using a 3D printer in construction was performed by Joseph Pegna in 1997. He formed cement into thin layers of sand and hardened each layer by the use of steam.[6] In April 2014, WinSun Decoration Design Engineering Co., was able to use a gigantic 3D printer to print ten houses. Each house covers an area of 200 m2 and was printed within 24 hours. Furthermore, the ink is made from construction waste, tailings and industrial wastes that were recycled. Each house costs approximately USD $4,800 to print.[7]

Potential benefits of 3D printing in construction include saving labour costs during the construction period. Traditional construction relies heavily on labour for the entire process, whereas 3D printing only requires labour for preparation and putting the parts together when printing is completed. Using a 3D printer would also save time and make the construction processes much more efficient. As mentioned earlier, a 200 m2 house would take less than 24 hours to print and the process has great potential to become even faster in the future as the technology matures. Currently, the most popular material used for construction printing is cement. However, architects in Amsterdam are currently printing houses using a plastic heavily based on plant oil. This project, if successful, will provide a greener option for house printing in the future.[8]


The technology of 3D printing has long been adopted by the automobile industry. Original equipment manufacturers (OMEs) have been using this technology to develop prototype parts during the design phase for the past 20 years.[9] 3D printers would allow users to design and prototype parts. The design phase can be shortened with the maturity of the technology and could also save costs in the developing stage. Modern 3D printing is also used to print body parts of cars. Ford 3D prints cylinder heads, brake rotors, and rear axles for test vehicles.[9]

Urbee, the world's first prototype car with its entire body 3D printed, was introduced in 2011.[10] It is a two-passenger car and designed to use the least energy possible. It is capable of reaching 200 mpg on the highway and 100 mpg in the city. The car was designed by the engineering group KOR Ecologic based in Winnipeg, Canada. The main concept behind the car is to have people drive a clean, energy-efficient car.[11] Currently, KOR Ecologic is working on Urbee 2 where not only the body but the inside of the vehicle will also be 3D printed. It is designed to be even more fuel efficient than the first generation and weighs less. Whereas the original Urbee was only a prototype, KOR Ecologic is aiming to put Urbee 2 in the market via crowdsourcing.[9]


The aerospace industry has also invested in 3D printing. 3D printing for aircraft components can result in lighter parts, shorter lead time, fewer materials required, and a reduction in the manufacturing process' environmental footprint.[12] Airbus has already produced a variety of plastic and metal brackets that has been tested and incorporated to the A350 aircraft. Airbus plans to deliver the A350-XWB by the end of 2014, which will contain 3D printed titanium parts.[12]

Consumer 3D Printing

With the continued innovation and expiry of key patents, 3D printers are increasingly becoming inexpensive and available for consumer use. The following includes examples of consumer 3D printers available by 2014 and 2015:

M3D Micro

The M3D Micro

The M3D Micro is a consumer printer developed by M3D Company and is expected to be priced at $349.[13] It is considered to be the largest 3D printer kickstarter ever, raising over $3.4 million compared to its $50,000 goal. It is also considered to be the most space-efficient 3D printer, with cubic dimensions of 7.3" per side and weighing only 1 kg. It uses auto-leveling and auto-calibration systems to maintain reliability and longevity.[14] Its software features a plug-and-play experience compatible with Mac, PC and Linux. The M3D Micro uses open-source software and supports .STL and .OBJ file types.



The MOD-t is a consumer printer developed by New Matter and is expected to be priced at $249. It was crowdfunded through Indiegogo and raised over $650,000 of its $375,000 goal. It uses a fused filament fabrication process, with an overall dimension of 15x11x14.5" and weight of 5 kg.[1] Its software includes the New Matter Desktop with an Online Store, compatible with Windows 7+, Macintosh OS X, Android and Apple iOS. The MOD-t supports .STL and New Matter Store file types. The printer also allows users to connect to Wi-Fi.


The LIX Pen is a variant of 3D printing that comes in the form of a pen that is expected to be priced at $140.[2] This product allows users to draw any imaginable shape in the air, eliminating the need for paper. It is developed by LIX and was crowdfunded through Kickstarter, raising over $1.3 million compared to its $55,000 goal.[3] Although not a 3D printer, the pen has similar functions. The pen is powered from a USB port, allowing it to melt and cool plastic to create rigid and freestanding structures.


The Mink printer is a consumer printer that allows users to print their own makeup and is expected to be priced at $300.[4] It was founded and developed by Harvard student Grace Choi and featured at a TechCrunch conference. The printer allows consumers to bypass big cosmetic retailers and produce makeup from the convenience of their homes. It allows users to select any color from the Internet to print into a blush, eye shadow, lip gloss or other types of makeup. The inkjet handles the pigment and uses inexpensive raw material substrates commonly found in high-end labels including powder, cream and lipstick.[5]

Implications and Controversies

Despite the growing awareness and demand for 3D printing, there are a number of implications and controversies surrounding the possibility of allowing the general public to print certain objects freely. 3D printing also has a number of implications for the future society regarding the environment, economy and laws, while controversies regarding the ability to print weapons (i.e. guns), body organs, and pharmaceutical drugs are subject to significant debate.

Environmental Impact

At first, 3D printing may appear to be efficient as only desired products are printed out. However, this advantage is offset by the fact that large amounts of energy consumption from heat and energy are used to melt down the materials needed for printing.[6] The most commonly used material in consumer printing, ABS plastics, are also non-recyclable; products that consumers print out on a whim quickly end up at the landfill.[6] Within homes, emissions from 3D printing can be dangerous for health as its effects are likened to leaving the stove on or lighting a cigarette.[6]

Economic Impact

Economically, 3D printing introduces various complications to the current society. It encourages innovation, as entrepreneurs have the ability to simply print small batches of their designs to test out various ideas while keeping a low financial risk. In operations, just-in-time manufacturing is also encouraged as manufacturers do not have to stockpile their products to meet unexpected demand.

Changes to the Manufacturing Process

However, 3D printing radically changes manufacturing processes as we know it to be today and it is likely that labour will be less involved in this automated process.[7] The middlemen (i.e. wholesalers and retailers) can be completely cut out. Another issue is that organizations will lose the control they have over their intellectual properties. Instead of purchasing copyrighted products, consumers will be able to 3D print their own replicas as long as they have the design blueprints. Gartner predicts that companies may lose up to $100 billion in the coming years from this phenomenon.

Legal Impact

RT America's News Feature on 3D Printing and IP rights

Consider the following example: a company releases its 3D designs for a bike helmet. It is downloaded by a user who prints it off using their own home 3D printer. However, it breaks during use and the user sustains injuries as a result. In this situation, who would be liable, the designers of the blueprints or the person who printed the design? The designer of the blueprint may have potentially designed a faulty product, but it is the user who brought the product into creation. Current product liability laws do not state how these types of situations should be handled.

As mentioned above, 3D printing will allow physical products to be pirated as it becomes more and more accessible to the average consumer. Government bodies will need to consider changes for current intellectual property and copyright laws to combat these violations.

Gun Control

The 3D Printed Liberator Pistol

With 3D printing, users are able to print anything, including dangerous weapons. As of 2014, fully functional pistols have already been 3D modelled and can be printed from any average 3D printer. The blueprints of the Liberator pistol created by the open-source Defense Distributed was posted publicly in May 2013 before the United States Department of State demanded that they be taken offline. During the two days it was made available, it was already downloaded over 100,000 times. To this day, it remains available on various file-sharing websites such as The Pirate Bay.

This granting of the public the ability to print guns hinders law enforcement's capacity of regulating gun possession, which often require licences that are only granted after thorough background inspection and examination. The U.S. Department of Homeland Security and the Joint Regional Intelligence Center attempted to address issues relating to 3D printing capabilities, stating that it poses a significant threat to public safety.[1] They acknowledge that legislations banning the printing of weapons may deter, but not completely prevent production and is synonymous to illegally downloading music and movies online which many deem nearly impossible to regulate.

The issue extends to the ability to detect 3D printed firearms. Since most objects produced by modern 3D printers are made completely of plastic, the possibility exists that metal detectors will be unable to detect concealed 3D printed firearms. This is illegal under the Undetectable Firearms Act, which expired on December 9, 2013. It was subsequently renewed but without any additions or changes to the regulation. The Department of Justice proposed more stringent prohibitions, including an expansion to gun types such as firearm receivers and magazines.[2]


The recent innovations regarding bioprinting have sparked ethical controversies relating to religion and economics. With Gartner's prediction that 3D-bioprinted human organs will soon be readily available, considerable political, moral and financial debates have arisen.

Many opponents to bioprinting argue that this technology provides unnatural extensions of life. Additionally, this innovation undermines determinism, the philosophical viewpoint that one's future is pre-determined.

In many countries, the sale of organs is considered illegal. The only legal way to obtain an organ is through a donor, free of cost. However, the demand for organs far exceeds the number of donors available. To meet this demand, black markets have been created, facilitating the illegal sale of organs for large amounts of money. This illegal market has created an “organ gap" between those who can afford to extend their lives and those who cannot.[3] Proponents of bioprinting argue that it will, in terms of its socioeconomic impact, bridge the gap between those who can afford expensive life-saving organ transplants and those who cannot. A matching of supply to demand, with the help of bioprinting, would enable for distribution of organs at a lower cost.

However, Pete Basiliere of Gartner questions the complexity of the initiatives.[4] Specifically, he questions who will have the ability to produce such organs, as well as the quality regulations required for such “products."


Lee Cronin's concept of a “chemputer."

One of the leading practicing scientists in the U.K., Lee Cronin, has proposed a highly controversial and innovative project, the Chemputer, which is a system that allows people to download medicine “files" and print from home. He predicts that the Chemputer will be used by pharmaceutical firms in the next five years and by the public in the next 20 years.[5] The caveat to the innovative project comes from Mike Power's book, Drugs 2.0: The Web Revolution That's Changing How the World Gets High. In the book, Power addresses the issue of being able to produce illegal drugs such as MDMA, LSD and cocaine. Power draws a comparison to illegally downloading files online, where users run the risk of accidentally downloading viruses as there is no regulation for such activity. Similarly, he questions the quality of the “drug files" being illegally downloaded and the potential for downloading a “bad file" which could lead to deadly outcomes.[5] Power admits, however, that allowing the public to do this will eliminate the role that drug dealers have in the black market and reduce the risk of receiving harmful, untested street drugs.

Our Thoughts

3D printing is a manufacturing process that we believe has immense potential. Recent innovations and the alarming rate at which it is advancing provides a glimpse of the impact it can make on existing industries as well as its future capabilities. The following section discusses our thoughts on 3D printing as a disruptive technology and its potential for future development.

3D Printing as a Disruptive Technology

Although 3D printing has a number of benefits, there are significant implications regarding its potential as a disruptive technology. As 3D printing continues to grow, we believe a number of industries, including pharmaceutical, cosmetic, healthcare, construction, and automobile, will be displaced.


With the idea of being able to create pharmaceutical drugs from home, there will no longer be a need to go to pharmacies. This will reduce the cost of drugs and its accessibility to third-world countries with limited pharmaceutical facilities. These all have severe implications for pharmaceutical firms in that they will no longer be physically selling medicine. Instead, they will be selling the rights to download drug files to print from home.


Grace Choi's Mink cosmetic printer has significant consequences for the cosmetic industry. According to Ernst & Young, the 2012 fiscal year shows overall sales figure exceed $254 billion for the beauty and personal care market companies, of which the makeup industry contributed 14%, or $35 billion.[6] Additionally, Estee Lauder is estimated to have a gross margin of 80% on sales, with L'Oreal at 70%, showing the profitability of the makeup industry.

With the introduction of the Mink printer, the margin of the highly profitable cosmetic industry is likely to plummet. In order to stay competitive, cosmetic firms will have to lower their prices and reduce the high profit margins that they boast. As the Mink provides convenience and variety to consumers, cosmetic firms will have to match that or change the way they operate completely to not only remain competitive, but to continue to exist as a market. If the cosmetic industry does not appeal to consumers, they may face a consequence similar to what film rental companies like Blockbuster faced against Netflix.


Just at the beginning the July 2014, researchers have announced that they are now able to 3D print working blood vessels which has been one of the biggest obstacle to prevent people from printing organs. In the future, if labs are capable of printing out full-sized functional organs at a low cost, it would have the potential to save thousands of lives that are waiting for organ transplant. Organ transplant is a very expensive and lengthy process simply because the people waiting for transplant outweigh the supply of organs. Bioprinting will reduce the wait time significantly and also ensure the fit of the organ since it will be custom-made for each individual.

Bioprinting already has an impact on companies producing medical stent and prosthetic limbs. Medical stent is often made from plastic or metal which can be rejected by the body, causing inflammation, abnormal tissue buildup and infection. However, a 3D printing stent can be made from biocompatible polymers which can reduce the risk of body rejection. It is very possible that in the future, scientists will be able to build bioprinted prosthetic limbs to replace the current artificial limbs.


3D printed houses would have a huge impact on current construction processes. Since machines can now build houses on its own, it can be estimated that there will be a significant cut in the labour forces, causing an increase in unemployment rate. However, this will shorten the construction period and save costs in human capital, transportation and materials used.

In traditional construction, the most used material for buildings are cement and wood. However, the most common material that is used in 3D printing construction industry is cement. When the technology matures in the future, there is a high probability that the market will show an increase in the consumption of cement and a decrease in consumption of wood. This would affect countries such as Canada that mass-export wood to foreign countries.



The aforementioned Urbee car was not only created with lower costs and in less time, but it is also more energy efficient as well as environmentally friendly. This implies that sooner or later, 3D printing will become the preferred manufacturing process of the industry.

The largest hurdle that the automobile industry faces with 3D printing at the moment is the limitations in sizes of printed parts. The largest 3D printer available at Ford as of September 2013 cannot create parts larger than 100 cm x 80 cm.[7] As the technology of additive manufacturing becomes more refined and allows for the printing of bigger parts, it will most likely force automobile manufacturers worldwide to reconsider their own operational processes.

Future Development

Gartner predicts that 3D printing will become mainstream in industries including medical, construction, automobile and aerospace within the next ten years based on the 2013 Hype Cycle for Emerging Technologies. However, the expiration of a key selective laser sintering patent in January 2014, as well as consumer printers utilizing open-sourced software, have sped up development and innovation.

Patent Expiry

Improvements in 3D Printing as a technology is partially held back by key patents being unavailable to players in the industry. As shown by the expiration of the fused deposition modelling and selective laser sintering patents in 2009 and 2014 respectively, large changes occur in the industry when popular 3D printing techniques are made available to everyone. The cost of using these techniques become much lower, and a result, 3D printers and their products drop significantly in price.

The following table is a list of key patents that have recently expired or will soon expire.[8] It can be expected that with the expiry of each of these, 3D printing will become more and more accessible to the public.

Open-Source Software

The increasing use of open-source software on consumer printers will further advance 3D printing development as it allows for ongoing innovative contributions from its users. Autodesk has announced a 3D printer including an open-source software platform called Spark for users to build and render their own 3D prints.[9] The Spark connects digital information to 3D printers to reduce the trial and error with printing and broadens the range of materials that can be used to print. It has been deemed to be a building block to new innovation, since it is open and available to anyone.[9] Because of this, it is seen as the future Android of 3D printing.

In 2007 the open source RepRap Project successfully produced the first self-replicating printer that is able to print a majority of its own parts.[10] Followed by the drop of the price of 3D printers, it is possible that 3D printing will become completely free for use in the future. However, the price of the materials may increase dramatically in order for businesses to profit.


  1. Winter, Jana. 2013. ‘'Homeland Security bulletin warns 3D-printed guns may be impossible to stop. Retrieved from: Fox News: http://www.foxnews.com/us/2013/05/23/govt-memo-warns-3d-printed-guns-may-be-impossible-to-stop/
  2. Defense Distributed. 2013. ‘'On undetectable firearms act renewal. Retrieved from Tumblr: http://defdist.tumblr.com/post/67342994298/on-undetectable-firearms-act-renewal
  3. Hampson, G. 2013. Bioprinting and immortality. Retrieved from National Science Communication Institute: http://nationalscience.org/blog/nsci-focus-areas/science-transfer/2013/bioprinting-and-immortality
  4. Rivera, J., and van der Meulen, R. 2014. ‘'Gartner Says Uses of 3D Printing Will Ignite Major Debate on Ethics and Regulation. Retrieved from Gartner: http://www.gartner.com/newsroom/id/2658315
  5. 5.0 5.1 Luimstra, J. 2014. ‘'Why there are two sides to 3D printed drugs. Retrieved from: 3D Printing: http://3dprinting.com/products/medical/3d-printing-drugs
  6. http://www.bidnessetc.com/business/3d-printing-set-to-rock-cosmetics-industry
  7. Dawson, R. (2013, September 24). Cars in 3D – the role of 3D printing in the auto industry. Retrieved from Automotive Megatrends: automotivemegatrends.com/articles/cars-in-3d-the-role-of-3d-printing-in-the-auto-industry/
  8. Hornnick, J., & Roland, D. (2013, December 29). Many 3D Printing Patents Are Expiring Soon: Here's A Round Up & Overview of Them. Retrieved from 3D Printing Industry: http://3dprintingindustry.com/2013/12/29/many-3d-printing-patents-expiring-soon-heres-round-overview/
  9. 9.0 9.1 Ribeiro, J. 2014. ‘'Autodesk announces 'Spark' open software platform for 3D printing Retrieved from PCWorld: http://www.pcworld.com/article/2155500/autodesk-to-offer-spark-open-software-platform-for-3d-printing.html
  10. Cite error: Invalid <ref> tag; no text was provided for refs named DigitalDialogue
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