From 3D printing to additive manufacturing – the missing narrative

What’s in a name?

3D printing is probably one of the most unfortunate names a new technology has ever been saddled with. Any introduction of a product or service on this naming basis has to jump the chasm of disbelief and incredulity, because “printing” carries with it the weight of hundreds of years of cultural and technical association with 2D and fluid, surface treatments on paper. It all sounds inherently small, flimsy, mechanical and disposable. Size, solidity, durability, permanence, etc. aren’t part of the conceptual vocabulary here. Which can be thought a big drawback when promoting breakthrough capabilities …

From destructive to additive

The interesting thing about 3D printing is that it involves a radical underlying change about basic manufacturing processes that have been around for centuries. In many such processes, manufacturing basically involves taking a large chunk of metal, wood, plastic, ceramic or stone, and then shaping, cutting, drilling, turning and otherwise finishing the larger solid element into something smaller, better, more useful and shaped for a particular purpose. The added value stems from the removal of material. This approach to manufacturing is fundamentally reductive and destructive, involving removal, waste, heat and damage as well as substantial investments in machinery, facilities and energy to remove what’s already there, has already been paid for, and has already had an environmental impact. There is an entire mindset as well as huge supplier constellations built up around this inherently wasteful kind of manufacturing process.

3D printing, on the other hand,  adds value by fabricating material that wasn’t there before, and is fundamentally additive, only adding and building up exactly what is needed and not wasting time, materials or energy on anything else. There’s a whole different logic in play here – a rethink of the fundamentals of fabrication and making the stuff we want and need in the most environmentally responsive and technically effective way. So I reckon the “additive manufacturing” moniker and mindset are (in general) much more appropriate for understanding and communicating the significance of the unfortunately named 3D printing. Which is probably still gonna’ be the term used for low-end, low-cost setups.

A bigger printing picture

Whatever the terminology we may use, 3D printing is far from new. One of the world market leaders, Nasdaq-listed Stratasys, has been in the business since 1988, but these remarkable fabrication capabilities don’t seem to have trickled down into mainstream consciousness or into full appreciation of the commercial perspectives and disruption potential. At the same time, many of the key players in this field apparently can’t and won’t reveal too much about what they’re really up to – first-mover advantage and big money are at stake.

However, one company seems a good example of a business that has sussed the strategic opportunities that stem from additive manufacturing, and placed them up front and centre in the company’s marketing (see below). Minnesota-based Evolve Additive Solutions hangs out its strategic shingle like this, making the potential impacts

clear. They also boast of a robust technology platform that seems set to change the way manufacturers across many industries fabricate products made with engineering plastics, elastomers and thermoplastics. And they at least do something to move beyond the world of 3D printing “just” being used in rapid prototyping, and to tease/show how the technology can be applied in mainstream manufacturing in customer-centric contexts.

Evolve Additive Solutions was apparently spun out from the Stratasys empire to exploit STEP technology  – the Selective Thermoplastic Electrophotographic Process – to use engineering plastics to fabricate objects by combining 2D deposition and 3D printing,  The company claims to be the first additive manufacturing technology to offer a viable commercial alternative to injection moulding and other traditional more-than-small-volume manufacturing processes, with seemingly remarkable production benefits to follow.

But then there is the high end of this manufacturing spectrum, working at the more advanced end of the market. Companies here – such as those working with advanced laser sintering for both plastics and metals, and with equipment that builds parts by fusing together more exotic materials like powdered titanium and superalloys – don’t want their machinery or capabilities confused with an inkjet printer or a simple ABS extruder. They’re pushing the adoption of their machinery and technologies as commercially viable alternatives to the likes of advanced CNC machining and injection moulding. Hence the term additive manufacturing being the moniker of choice for this class of vendors.

High-end angle – jet engines

One of the industries furthest forward with additive manufacturing techniques capable of withstanding extreme conditions (and thus providing credible demonstrations of the viability of the technology) is the manufacture of aircraft engines and – in particular – turbofans. Here, additive manufacturing (i.e. being able to fabricate exactly what you want, rather than what multi-axis CNC shaving allows) has opened up new technical capabilities and commercial opportunities involving technologies that include:

• · Ceramic matrix composites, in which high-spec fibres are embedded
• · Directional solidification of complex alloys
• · Single-crystal structures, “grown” from a single complex crystal
• · Superalloys and intermetallic compounds made using solid solution strengthening and other advanced techniques

This is where we mere mortals can get a glimpse of the real potential of additive manufacturing, with opportunities for shapes – sometimes hollow and with specially designed cavities and cooling channels, often featuring complex geometries and compound curvatures, etc. – and materials simply inconceivable for traditional reductive milling and machining.

Aircraft manufacturers also use a perspective known as the “buy-to-fly ratio” – the amount of material required for the amount of material that actually goes on the plane. In a 2018 Boeing ecoDemonstrator programme, they were able to replace a part conventionally milled from a solid block of titanium (with a 10:1 buy-to-fly ratio) with a part printed using additive manufacturing techniques, featuring a 2:1 buy-to-fly ratio. This represents a drastic reduction in waste, and the business logic is fairly clear.

Democratisation of opportunity

It’s not just at the fancy end that things are changing – fast. An August 2019 Kickstarter campaign for an SLA 3D printer was over-subscribed by more than 400% two weeks before the campaign had even closed. The Shenzhen-based SolidMaker uses stereolithography (SLA) technology to provide high-resolution results with smooth finishes that you can’t get from FDM, DLP or even LCD printers – according to experts. It uses a precision UV laser to cure photosensitive resins into 3D objects with remarkable detail, in a printing area of up to 120 x 120 x 150mm.

SolidMaker is profiled as being ideal for making 3D objects of medical, design and architectural models, engineering prototypes and other large-scale formats in a single print, using most of the standard resins currently available. With a USD 400 Kickstarter price point and a planned retail price of USD 699, fast, high-performance 3D printing is suddenly within reach for a wide range of artisans, designers and small businesses.

Deeper digital transformation

Regardless of how transformative 3D printing or additive manufacturing may seem and regardless of the hardware used, there’s also a deeper change taking place. A prime example is Carbon, started in 2015 and now one of the world’s leading digital manufacturing companies. The company uses Digital Light Synthesis™ (DLS) technology that makes it possible to move beyond traditional additive manufacturing trade-offs between finish and mechanical properties – by using digital light projection, oxygen-permeable optics and programmable liquid resins to produce high-resolution polymeric products with engineering-grade mechanical properties and exceptional surface finish.

Digital Light Synthesis™ is driven by the CLIP™ photochemical process, which works by projecting light through an oxygen-permeable window into a reservoir of UV-curable programmable liquid resin. Once a part is printed with CLIP™, it gets baked in a forced-circulation oven, setting off a secondary chemical reaction that then causes the materials to strengthen.

It seems that DLS technology makes it possible to create complex-shape products at speeds and volumes never previously possible, thus finally delivering on the apparent promise of 3D printing, making it feasible to deliver at scale and move beyond merely marginal manufacturing capabilities. But there’s more to Carbon capabilities,

Squishy or complex

Ultimately, it doesn’t really matter whether we call it 3D printing or additive manufacturing. The processes are pretty similar, both rooted in layer-based manufacturing techniques. Each has its strengths and weaknesses, depending on the material, machinery and technology used, and the purpose for which it is intended.

My homemade rule of thumb about this nomenclature is that if the basic material is somehow squishy and fluid, it falls more logically into the 3D printing category, whereas if it’s more technically complex (often involving powders, crystals and lots of electricity) it probably fits better into the additive manufacturing pile – with this as the overall generic term, too.

A mindset about opportunities

What really matters most is that we take advantage of these advanced new processes, machines and technologies where they make best sense – whether that be upfront in the design process, in engineering testing, in manufacturing, or in the final product – in large or small batches. From CEOs to engineers to designers, a lot of people are getting excited about the amazing stuff they can design and fabricate using additive manufacturing, and the efficiencies and cost savings that go with it. Because no one likes inefficiency, waste or landfill, right?

But to help make this happen the entire additive manufacturing narrative needs to be stronger and more centre-stage, to bring these remarkable capabilities to the attention of forward-thinking fabricators, large and small.

In March 2020, one company scored a brilliant PR coup for 3D printing and its potential. Belgium-based Materialise developed 3D-printable door openers so people don’t have to actually touch door handles, thus helping reduce the risk of Covid-19 spread. The company then made the design files freely available, so anyone can benefit and manufacture them quickly, on site and on their own terms. This is also a brilliant illustration of

one of the strategic benefits of 3D printing – the ability to rapidly repurpose capabilities at short notice, to meet new needs. The manufacturing technology is no longer slaved to any specific output format.

In fact, the biggest challenge for 3D printing/additive manufacturing lies not in the technology, the materials or their capabilities, but in perceptions of them. In early 2022, Hypersonix Launch Systems in Australia and Kratos Defense and Security Solutions in the US agreed to launch the Dart AE, which is described as a “multi-mission hypersonic drone technology demonstrator”. This aerial vehicle will travel at speeds in excess of Mach 5 over ranges of 500+ km, but the distinctive thing is that it will be built using additive engineering, and the whole platform will be 3D printed. If the technology can deal with such operating conditions, it’s probably about time for perceptions of wonkiness to be put aside.

PS For anyone keen to quickly catch up on what’s happening in the world of 3D printing/additive manufacturing, Fabbaloo and All3DP.com aren’t the worst places to start. And this overview from Evonik (“power to create”) gives some good hints, too. The Materialise timeline also gives a good appreciation of the vast number of “sub-disciplines” within the world of 3D printing.