This is a two part series on 3D printing. Stayed tuned for “3D Printing Our World” in the next edition of Eysight.
“There will be a 3D printer in the home of every person and on the desk of every office.” It was promised to us years ago and yet it never materialized. But while consumers will never own these machines outright, they do experience the products fabricated by industrial printers.
Whether the machine is printing with resin, metal, concrete or even human cells, 3D, or three dimensional, manufacturing is rapidly developing and may soon conquer the realm of traditional fabrication. 3D printing was never overhyped, the attention was simply in the wrong direction—these machines never belonged in the homes of everyday citizens but in the warehouses of manufacturing giants and in the workshops of innovative designers.
Source: The Economist
What is 3D Printing?
3D Printing, or additive manufacturing, is the process of making three dimensional objects by adjoining successive two-dimensional layers. While once standing for the specific process of producing parts from filaments, the term now represents a variety of technologies united around the common attribute of layer-based fabrication. There are currently three leading 3D printing technologies that dominate the industry.
Fused filament fabrication (FFF), the technology most commonly associated with 3D printing, creates parts by melting and extruding filament through a nozzle that is constantly moving around a plane. The build platform lowers itself by some small increment upon completion of a layer. Fused filament fabrication is mostly used for rapid prototyping of relatively simple parts.
In Stereolithography (SLA), light curing machines use lasers to photochemically cure liquid resin layer by layer into solid parts. The printer selectively shines ultraviolet light to create the desired cross section and an elevator will then submerge the cured resin just below the surface; this allows the printer to cure the next layer onto fresh resin which will bind with the previous sheet. Stereolithography offers high precision and design flexibility at the cost of slower production times and with constrained material types.
Selective laser sintering (SLS) creates parts by way of fusing metal or plastic in a powder bed together. A flat pile of fine powder is assembled on a tray where a laser effectively welds the top surface into a connected layer; an incredibly thin sheet of loose powder is then brushed over so the process may start again. Selective laser sintering is best for production requiring exotic materials. It offers high production quality for a low cost of materials while sacrificing production speed and having a high equipment cost.
The models depict fused filament fabrication (FFF), Stereolithography (SLA), and Selective laser sintering (SLS) respectively.
Sources: 3D Printing and Design, CraftCloud
Public knowledge of the technology is mostly limited in scope to consumer printers sometimes found in classrooms and makerspaces. While fascinating, the utility of additive machines of this scale is limited to replacing broken parts and introducing students to design. If anything, they inspire more awe than they deliver in merit. Use of the technology in this way is certainly not revolutionary.
The world of 3D printing is a broad and exciting industry once the curtains are pulled back. Behind the scenes, additive manufacturing is transforming mass production, international shipping, and even the way innovation is imagined.
From Rapid Prototyping to Rapid Development
For most of 3D printing’s 35 year life, the technology has been solely reserved for prototyping and other low volume purposes. Because the machines were too expensive and the printing was too slow, additive manufacturing was only used when initial designs needed to be visualized and tested. This is still mostly true today with over 70% of manufactures reporting that they use 3D printing to prototype, according to Forbes. What has changed, however, is that a majority of these companies now label production as an application for their printers. And it was rapid development within the space that made additive manufacturing practical.
As of 2019, 51% of manufacturers reported production as an application for 3D printing. This is compared to 62% and 71% for proof of concept and prototypes respectively.
Source: Forbes
The first development that launched 3D printing into mass production was an exponential increase in printing speeds. While Moore’s law traditionally dictates processor density, its theory can be applied to 3D printing speeds as well. According to Avi Reichental, the former CEO of 3D Systems, printing speeds at his company doubled every 24 months over the past 10 years. Parts that took 16 hours to complete a decade ago could now be printed in under 30 minutes. While this is an interesting parallel to Moore’s law, it must be noted that extrapolations must be made with extreme care as past results do not guarantee a future trend.
The second wave of progress came with drastic price reductions. Following a similar pattern of exponential change, the average cost of a 3D printer dropped from almost $300 thousand in 1992 to $150 thousand in 2005. An industrial printer now costs a manufacturer less than $40 thousand.
Source: 3D Printing Industry
While more abstract, the final developments of 3D printers have been an increase in quality and range. The early products of additive manufacturing were coarse and brittle. Now not only has the makeup of resins improved, but faster techniques allow the material to dry in a way that forms a more durable and connected structure. Additionally, the three main processes (FFF, SLS, and SLA) of 3D printing allow for higher production quality depending on the design required.
With these developments, it became practical for manufacturers to incorporate additive manufacturing directly into their supply chains. This was a feat once deemed impossible by the traditional manufacturing industry.
Massless Production
In most cases, it is logical to assume that subtractive manufacturing, the process of creating a final part by removing material from a solid block; and forming manufacturing, the process of creating a final part by filling a mold with liquid material, would be more cost effective in mass production. However, 3D printing introduces several externalities that make additive manufacturing a real competitor in end use products.
The first industry subset that additive manufacturing is taking over is customization. Because these products require subtle variations for every consumer, it is inefficient and wasteful to mass produce a base form from an injection mold and then subtractively carve it until perfect. This is especially true in the hearing aid industry, where 98% of products are 3D printed. Tasha Keeney of ARK Invest notes that it took less than two years for companies to completely switch over to the new technology as 3D printers were simply able to produce at a lower cost and higher quality than with other methods.
3D printing is also being used to design custom braces and body parts for amputees.
Source: Design Engineering
Keeney believes that 3D printing’s rapid gain in market share of hearing aids from less than 1% to over 98% in the space of only 24 months is telling for the future of the industry. Once additive manufacturing becomes practical for a specific field, companies must adopt it quickly or they will not be able to remain cost competitive. Keeney described this as “the tipping point.”
3D printing is also applicable where parts are complex and weight is important. One fundamental advantage of 3D printing is that the manufacturer has a high degree of control over the final design. Because this form of fabrication is so precise, it allows for parts to be selectively hollowed in a way that maintains the item’s structural integrity. Because subtractive manufacturing begins with a solid mass of material, the inside of a part must also be solid. With 3D printing, material can be added in a grid-like structure that maintains nearly all of the strength of a solid part while reducing mass by over 80%.
With the gear, for example, 3D printed versions are significantly lighter because their interior is filled in with a honeycomb pattern, as opposed to a solid mass.
Source: Nano Dimension
The hollowing of parts is especially crucial in the aerospace industry, where “one less kilogram of weight will save half a million liters of fuel over the 30-year lifespan of an A350,” according to Airbus. In a space where tiny margins have large impacts on profitability, even a miniscule reduction in weight can significantly impact the bottom line. Michael Sillus, manager of the Emerging Technologies Division at Airbus, reported that the introduction of one 3D printed part reduced the weight of the aircraft by over 4 kilograms.
The introduction of 16 of these door locking shafts (two per door) into the A350 shaved 4 kilograms off the final weight.
Source: DW Documentary
By nature, additive manufacturing is more efficient than traditional forms of fabrication. This is relevant with reducing the number of moving parts in a system which eliminates points of weakness, cuts down on weight, and lowers cost. Tasha Keeney noted that “GE… has one part that goes in the turboprop engine. It used to be over 800 pieces and now it's just 12 with 3D printing and with that reduction you also get 20% less fuel burn.” Because material is being added together to form a part, fine detail can be ensured that is lost when material is crudely cut off to form a model. For example, the resolution of the part depicted below could never be achieved from milling.
This part is fabricated using selective laser sintering (SLS) and has two degrees of freedom due to multiple functioning joints and a spring. While this mechanism would typically contain over a dozen pieces, this model is only one part.
Source: 3D Printing Nerd
There is one final, subtle, but important advantage of manufacturing using 3D printers: an expedited process from the product pitch to delivering the item on the market. Because 3D printing is inherently more intertwined with prototyping, the design and development process with additive manufacturing is far less rigid. While a normal company may wait weeks outsourcing the production of a small part that cannot be produced in-house, there is hardly any wasted time when utilizing 3D printing. Producing using additive manufacturing has the unique benefit that all parts can be quickly designed and created, which streamlines the development process. Local Motors, an automotive startup, has used 3D printing to manufacture an electric car.
“Traditional manufacturing is five to seven years from a decision to build a vehicle to see the first product come out—we are 12 months total to a sellable product so… at a minimum, we're five times faster”
— Jay Rogers, CEO of Local Motors
The First 3D Printed Car, The Strati by Local Motors
Source: Popular Mechanics
Development haste is especially significant with innovation. While many automotive giants are still struggling to bring their first electric vehicle to market, following Tesla's success, additive manufacturing allowed Local Motors to complete development faster than any other company in the field. Simply, the introduction of 3D printing into the supply chain shortens production time.
The Volume Problem
There is one crucial issue that holds 3D printing from conquering more than 1% of the manufacturing realm: the volume problem. The achilles heel of additive manufacturing is that it does not follow economies of scale.
Injection molding has historically been an industry favorite due to its cost down curve that quickly approaches the price of materials. Essentially, after the high startup cost of building the molds, the product can be mass produced, lowering the average cost with every unit made. With additive manufacturing, however, the cost begins fairly low as multi-purpose 3D printing machines can be used to begin printing immediately, but the cost never lowers because each unit must be fabricated individually. This leaves a small, low volume window where 3D printing is more cost effective, but renders the technology ineffective when many identical units are being produced.
Source: Slant 3D
Thankfully, as printer costs continue to lower and printing speed continues to increase, the average cost of printed goods will decrease, pushing the line down and widening the cost effective window for additive manufacturing.
This is already being observed with a partnership between Carbon, a 3D printing unicorn, and shoe manufacturers like Nike and Adidas. The shoe companies have hired Carbon to manufacture shoe soles due to their improved performance and to lower material waste.
“No-one's ever taken 3D printing at a high-volume. Adidas represents a seminal moment, I would argue, in the history of industry where we've got volumes that now allow us to have a cost down curve just like injection molding. This process could present a cost-effective alternative to conventional mass production methods. Two years ago it took more than two hours to print a shoe sole like this one—now it takes just 30 minutes. This will allow the 3D printing world to go from a 10 billion dollar prototyping world to a three hundred billion dollar manufacturing juggernaut.”
— Joseph DeSimone, Carbon Cofounder and Chairman
Early results of these partnerships have been more than promising as Nike’s 3D printed Vaporfly is under scrutiny for being too light and efficient as to give an unfair advantage to the runner. Comically, their design was too cutting edge that it disadvantaged competitors that didn’t have 3D printed shoes. Both companies plan to further implement additive manufacturing into their assembly lines in the near future.
The outsourcing of large-scale shoe sole production to 3D printing as a service companies like Carbon represents the potential for additive manufacturing to become an essential part in the global mass production market.
Source: CraftCloud
The Endgame of Additive Manufacturing
With so much development, the 3D printing industry is set to experience rapid growth over the next decade. As additive manufacturing becomes a proven and sustainable technology, more firms are entering the market space, further lowering the cost of products. In fact, the Wohlers Report noted how the number of 3D printing companies increased by over 30% from 135 in 2018 to 177 in 2019. This increase in competition is validation of its market potential. These developments have not gone unnoticed by the market. According to Essentium, the number of their respondents using 3D printing technology for “full-scale production” has doubled from 21% in 2018 to 40% in 2019.
In fact, even companies like Lamborghini and Hasbro are turning to 3D printing for end use products. While Lamborghini and other auto manufacturers have implemented 3D printed parts into their newest car models to reduce weight and drag, Hasbro has favored the technology for mass production for toys with complex designs. CEO Brian Goldner noted how Hasbro “believe[s] 3D printing offers endless potential to bring incredible new play experiences for kids.”
As the price of additive manufacturing continues to fall, the number of industries that will be able to take advantage of the technology will only increase. While mostly confined in the realm of prototyping today, 3D printing could soon pose a threat to Ford’s century-old assembly line.
This is a two part series on 3D printing. Come back next time to learn where to invest in the technology and how additive manufacturing is being used to print human hearts, ship goods at light speed, and transform the innovative process itself.
Sources
Forbes - 3D Printing Revolution