3D printing explained, and how it will rock the world

March 31, 2016

3D printing is not just one process. "3D printing" and "additive manufacturing" are umbrella terms for many different technologies and processes. Each...

3D printing is not just one process. “3D printing” and “additive manufacturing” are umbrella terms for many different technologies and processes. Each type of 3D printer builds parts or products layer upon layer, usually from the bottom up, sometimes from the top down.

3D printers have been around for about 30 years. Until recently, they were used mostly in industry for rapid prototyping. Beginning in 2009, early 3D printing patents for Material Extrusion started to expire, which led to many startups offering Material Extrusion machines (often called Fused Deposition Modeling (FDM) or Fused Filament Fabrication (FFF) machines) entering the market. This created a consumer side to the 3D printing industry. Around the same time, industrial 3D printers got good enough to start making end-use production parts, so today the industrial machines are used for both prototyping and production. Industrial machines can make end-use production parts for aerospace components, jigs and fixtures for automotive manufacturing, and customized healthcare products, such as cranial implants, surgical models, and teeth aligners.

The most common types of 3D printing technology are described below:

Binder Jetting

Also called digital part materialization (DPM), is an inkjet method somewhat like a 2D inkjet printer. Binder Jetting employs one or more jets to dispense chemical binders layer-by-layer into a bed of powdered polymer, stainless steel, bronze, tungsten (or soda lime glass powder), or sand for making molds. These machines make excellent molds and can also make finished, full-color parts after additional heat treating. 3D Systems (United States) and ExOne (United States) make industrial-grade Binder Jet printers. Voxeljet (Germany) makes Binder Jet printers with a very large build platform. A Voxeljet machine 3D printed replicas of James Bond’s Aston Martin DB5 for the movie Skyfall.

Directed Energy Deposition

“Laser Engineered Netshaping” or laser cladding

Directed Energy Deposition (DED) is also known as laser cladding. Perhaps the best examples of DED systems are the Laser Engineered Netshaping (LENS) machines made by Optomec of Albuquerque, NM. LENS machines employ deposition heads, which are similar to inkjet heads, to supply metal powder to the focus of a laser beam, which melts the powder into the desired shape. Using multiple metal inputs, these machines can 3D print metal alloys on the fly. LENS machines make structural finished parts. Trumpf (Germany) has a similar DED process, and both DMG Mori Seiki (Germany/Japan) and Yamazaki Mazak (Japan) make a hybrid DED machine and multi-axis computer numerical control (CNC) mill. EFESTO makes a laser cladding machine that builds up layers of metal on existing parts. NASA and Penn State University are using the Efesto machine for a process they call Radiant Deposition, which builds up layers of metal powder radially on a rotating rod. The metal powders can be changed while a part is being built, also creating metal alloys on the fly.

Electron beam freeform fabrication

Electron beam freeform fabrication (EBFF) focuses an electron beam on metal alloy feedstock in wire form, which is fed into the beam in a vacuum, creating a molten metal pool that solidifies immediately. NASA plans to use EBFF machines to build parts in zero gravity. Sciaky (United States) calls its version of this process electron beam additive manufacturing (EBAM), and makes a giant version (9 x 4 x 5 ft.) that welds wire feedstock with an electron beam.

Material Extrusion

Fused deposition modeling (or fused filament fabrication)

Fused deposition modeling (FDM) machines extrude a thermoplastic filament, usually acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), through a tiny heated nozzle onto a build platform, building the part from the platform up. A second nozzle may extrude material to create supports that are removed after the part is built. Most consumer-level 3D printers are FDM machines, which flooded the market after early FDM patents started to expire in 2009. Currently, hundreds of companies, most of them start-ups, manufacture consumer-grade FDM machines worldwide. In the prosumer and industrial arenas, FDM machines are used mostly for prototyping, but may be used for finished plastic parts. Stratasys, an industry leader, pioneered FDM machines. Stratasys’s subsidiary, MakerBot, makes consumer- and prosumer-level FDM machines, as do 3D Systems and many small companies.

Material Jetting

Aerosol Jet

Aerosol Jet machines, also called direct-write machines, use a mist generator to atomize a wide range of metal or non-metal build materials to print circuitry or parts on a variety of substrates, including onto existing parts. In this process, print-head nozzles deposit inks, such as silver nanoparticles, with extreme precision onto various substrates to make micro- and macroscale structures, such as electronic circuitry. The aerosol stream of build-material particles is refined on the fly and aerodynamically focused as it is deposited. After being deposited on the substrate, the materials may be thermally or chemically treated. Optomec (United States) is the leader in this technology. Its machines can 3D print circuitry on any substrate. Camtek’s printed circuit board printer (Israel) and Neotech’s light beam sintering (Germany), as well as Nano Dimension (Israel), nScrypt (United States), and XJet (Israel), seem to be using similar technology. The Lawrence Livermore National Laboratory is also working in this area.


Like Binder Jet machines, PolyJet machines are also multi-jet inkjet-like machines. The difference is that while Binder Jet machines jet binders onto powdered build material layer by layer, PolyJet machines jet actual build material layer by layer. Most use UV light to cure the layers of photopolymers. PolyJet machines can print multiple materials simultaneously (including support materials that are removed from the final product) and are suitable for making finished parts. PolyJet machines are made by 3D Systems, Stratasys, and Solidscape.

Powder Bed Fusion

Laser melting

Laser melting (LM) machines (also known as direct metal printing, direct metal laser sintering, metal laser melting, selective laser melting, selective laser sintering, and laserCUSING) are powder bed machines that use a laser to melt layers of plastic, ceramic, or metal powders. Because the part is fused from the surrounding bed of powder, sometimes no support structures are needed; the surrounding powder provides support, then simply falls away when the part is removed from the bed. These machines can make finished parts with complex internal and external geometries. EOS (Germany) machines use this process to make tooling and medical implants, and GE uses it to make aircraft parts, such as fuel injectors for the leading edge aircraft propulsion (LEAP) engine. Using Powder Bed Fusion, GE 3D printed, as a single piece, a cobalt-chrome fuel nozzle that formerly had been assembled by welding together twenty different parts.

3D Systems/Phenix, which calls its process direct metal printing; Concept Laser (Germany), which calls its process laserCUSING; EOS, which calls its process direct metal laser sintering; Renishaw (United Kingdom); and SLM Solutions (Germany), which calls its process selective laser melting, all make laser melting machines. Matsurra (Japan) makes a hybrid machine that combines laser melting and a CNC mill. Laser maker Fonon (United States) also makes a laser sintering machine for metal powders.

Electron beam melting

In electron beam melting (EBM) machines, an electron beam builds up parts from a powder bed in a vacuum. Similar to laser melting machines, EBM machines make finished structural parts. Sweden’s Arcam is the leader here.

Sheet Lamination

Laminated object manufacturing

Laminated object manufacturing (LOM) machines laminate sheets of paper, plastic, or other materials, which are then cut into the desired shape with a laser or knife. LOM machines are well suited to making models, which feel somewhat like paper mache. MCOR (Ireland) makes LOM machines that print full-color models using standard photocopying paper. A particularly freaky example is a full-color model of an MCOR employee’s disembodied head.

Ultrasonic lamination

Another Sheet Lamination company, Fabrisonic (United States), uses a 3D printing process called ultrasonic additive manufacturing (UAM), in which sound waves fuse layers of metal foil.

Vat Photopolymerization

Digital light processing

In digital light processing (DLP), mirrors project the image of each layer of an object onto the surface of a vat of photopolymer. The light source cures the image, building up the product layer by layer. Germany’s EnvisionTec and several smaller companies make DLP machines.


Stereolithography (SLA) is the granddaddy of them all, the original form of 3D printing commercialized in the 1980s by Chuck Hall, who went on to form 3D Systems, an industry leader. SLA machines use a UV light source to cure a vat of liquid photopolymer resin, layer by layer. SLA-printed parts have a smooth, close-to-finished surface and are well suited for making jewelry molds. SLA can also be used for prototyping and making simple finished parts. Most SLA machines are prosumer or industrial, but consumer-level SLA machines include the Formlabs, Autodesk EMBER, and B9 SLA printers. Industrial-grade SLA machines are made by 3D Systems. The Lawrence Livermore National Laboratory is developing a high-speed variation called microstereolithography to create ultrastiff but lightweight parts.

Bringing jobs home

One of the strengths of 3D printing is customization. So rather than making millions of parts that are all the same, 3D printing’s strength is making a million parts that are all different. Today, industrial 3D printers are used mostly for complex or highly customized parts and small production runs. As the machines get faster, they will make larger production runs, but the strength of the technology is mass customization, not mass production.

Because 3D printers can make entire parts or products with fewer machines, fewer steps, and therefore fewer people, they can eliminate the benefits of making things where labor is cheap. The implications are obvious: more manufacturing in America, but not many jobs running the machines. Ten manufacturing jobs lost in low-wage countries may create only one job in a 3D printing economy, but let’s be careful to compare apples to apples. If it takes ten people to operate the traditional machines needed to make a single part, it may take only one person to operate the 3D printer that makes that part in America. To the optimist, that is one more manufacturing job than we had without 3D printing. To the pessimist, we still need nine more jobs. But the pessimist is missing an important point: if the part is made in America by a local worker operating the 3D printer, most of the supply, support, and distribution chain will be here too.

Regional and distributed manufacturing

Because chasing cheap labor is unnecessary in a 3D printed world, this technology can break the grip of centralized manufacturing. But don’t assume that huge factories will simply replace their traditional machines with 3D printers. As 3D printers become more and more capable of making almost any finished product, centralized mass production may no longer be needed and, as a business model, may become as antiquated as the dinosaur. 3D printing will pull manufacturing away from the manufacturing hubs and redistribute it, product by product, among thousands or tens of thousands of smaller factories across the globe. Many parts and products will be made regionally, close to where they will be used.

End of the line

The days of thousands of unskilled American factory workers performing highly repetitive, mindless tasks along an assembly line are gone for good. The factory of the future will be inhabited mostly by 3D printers, robots, and other advanced machines, all driven by software. Some people will be needed on the factory floor to make sure everything is humming along, but the jobs they will do may not exist today.

As technology advances, there will be little place on the factory floor for unskilled workers. In fact, even today there are fewer and fewer jobs for workers without skills or a college education. Between October 2008, when the world economic crisis began, and mid-2014, the US unemployment rate hovered in the 6–10 percent range. During that same time period, the unemployment rate for college-educated workers was only about 3–5 percent.

In a 3D printed world, the demand for skilled workers will increase, but we don’t know yet exactly what their jobs will be like. People will be needed at every step of the now-localized supply and distribution chain, even though their jobs will be radically different than they are today.

Think about the horse

So if 3D printing factories will not employ many people and most of the jobs will be for skilled workers, how will 3D printing spark a new industrial revolution, a manufacturing renaissance, and bring jobs home? Think about the horse.

When the horse was the main form of transportation, there were many horse-related jobs: saddle makers, blacksmiths, wagon makers, stable owners, feed suppliers, etc. When the automobile came along, most of those jobs were lost. But think of how many new jobs were created by the invention of the automobile. 3D printing has the same potential.

New businesses, new jobs

3D printing will spawn businesses, products, services, and jobs that are as unimaginable today as the auto industry was at the dawn of the twentieth century. Of course my crystal ball is not perfect, but some types of 3D printing-related jobs are suggested by its strengths.

Regional manufacturing means most players will be independent fabricators. A growing number of 3D printing fabricators can be found throughout the world. 3D printing fabricators are the regional and distributed manufacturers of the 3D printing age. They are the employers of the factory workers of the 3D printing–fueled manufacturing renaissance. Individually, they may not employ a large number of people, but together they will be a major source of factory jobs.

3D printing, regulation, and the American national pastime

Because 3D printing will have profound effects on stakeholders – companies, consumers, governments, and economies – it is bound to rock the law. Intellectual property (IP) law is mentioned most often, but the legal effects of 3D printing will be much broader. 3D printing will certainly affect IP law, but challenges to product safety and product liability law will probably have more relevance to most people in a 3D printed world.

Government regulators will also be challenged. Healthcare regulators will be faced with approving countless 3D printed medical devices, drugs, and human organs. Aviation regulators will face the same issues with 3D printed aircraft parts. Consumer products regulators will grapple with the safety of 3D printed products. 3D printing may also challenge governments’ abilities to collect income and sales taxes, and to control the export of technology that may be used for nefarious purposes. 3D printing new kinds of crime will challenge law enforcement, investigation, intelligence, military, national security, and criminal justice systems. It will lead to calls for new laws to address the dark side.

Americans have two national pastimes. One is baseball and the other is suing each other. As companies and people are negatively affected by 3D printing, they will complain, then sue. Some will try to get Congress to enact new laws to protect their interests. Others will look for creative, positive approaches and trust in the free market system. It would be nice to think that the stakeholders will work out their problems in proactive, creative, and amicable ways. But it is more likely that 3D printing will be as much of a full-employment program for lawyers as the Internet has been.

John Hornick has been a counselor and litigator in the Washington, D.C. office of the Finnegan IP law firm for over 30 years. He is the author of the new book, 3D Printing Will Rock the World, and advises clients about how 3D printing may affect their businesses, frequently writes about 3D printing, and has lectured about 3D printing all over the world.



LinkedIn: www.linkedin.com/in/johnhornickip


John Hornick, 3D Printing Will Rock the World