In this 3-part article series, we will address the important issue of Design for Additive Manufacturing (DfAM). Part 1 discusses the evolution of product design to provide context in terms of the state of the design industry when 3D printing first emerged and how the two sets of technologies (digital design and printers 3D) evolved in parallel. This will provide a broad historical perspective illustrating how current design processes inform the successful adoption of industrial 3D printing for a wide range of applications. Parts 2 and 3 will explore the intricacies of designing specifically for 3D printing, the advantages it offers over more traditional manufacturing processes, and the pitfalls to avoid to get the best results.
The story of 3D printing (3DP)/additive manufacturing (AM) dates back almost 35 years and as a set of technologies it proved disruptive across many industry sectors and continues to evolve and disrupt to this day.
In its early days, what is now called additive manufacturing or industrial 3D printing began its journey as a technology universally referred to as rapid prototyping (RP). Indeed, it was seen as a technology that allowed design engineers and manufacturers to easily, quickly and inexpensively produce physical prototypes of their new products/components.
It’s also pertinent to remember that in the 1980s, digital design was also relatively new. Indeed, it was advances in 3D CAD that helped facilitate 3D printing itself. Product development – including design – is an iterative process and taking a product from idea to manufacturing involves many steps, often in a linear/circular fashion. This includes going through many iterations of a product to optimize it – taking into account market research feedback and manufacturability. Designing for the manufacturing process of choice has always been one thing.
When 3D printing really took off as a means of rapid prototyping in the 1990s, it offered companies a viable and economically attractive way to produce multiple design iterations to optimize the final product without lengthening and often shortening lead times. It’s also essential to note that rapid prototyping and 3D printing – then and now – are used as umbrella terms for a number of different additive processes. There are a total of seven types of additive manufacturing processes.
The very first process was stereolithography (SLA), a TVA curing process, which used resin materials, which resulted in the first commercial 3D printing system – the SLA-1 – from 3D Systems Inc. It was closely followed by two others: the Selective Laser Sintering (SLS) process, originally developed at the University of Texas and commercially licensed by DTM Corp; and Fused Deposition Modeling (FDM) process developed and marketed by Stratasys Inc. SLS now falls under the name of generic Powder Bed Fusion (PBF) process, while FDM falls under the name of Material Extrusion Process . The other four additive manufacturing processes that are now well established are material jetting, binder jetting, directed energy deposition, and sheet lamination.
The main advantage offered by 3D printing for rapid prototyping, and the reason it took hold, is that it enabled a concurrent or concurrent engineering approach that eliminated the existing linear/circular silo culture of product development and drastically reduces design to market. deadlines and costs.
3D printed prototypes remain a universally accepted and dominant application of the technology defined today.
The thing to note here, however, is that 3D printing offered a way to improve the product development process – it didn’t affect the nature or methodology of the design itself. It was basically originally integrated as a useful tool for improving the development process (including design improvement through iterative feedback) for existing traditional manufacturing processes.
Throughout the 1990s, early adopters emphasized progression by including tooling managers in the product development process much earlier – sometimes just days into the product lifecycle rather than weeks or months. traditional than it would usually take. As a result, they were able to provide valuable insights that helped avoid costly mistakes and speed time to market. Further evolution saw the tools themselves become a key application of 3D printing – this is the nickname of rapid tooling. This application area provided a very cost effective way to produce tools for low and medium volume products. Again, this is still a viable application of AM technologies today.
Over time – and increasingly successful over the past 10 or so years – 3D printing has begun to evolve from a prototyping or tooling technology to a true production technology, evidenced in the terminology used to describe it today: additive manufacturing or industrial 3D. impression.
With this change, the ability of AM to continue its disruptive role was redoubled, as the focus was now on whether and how the various AM processes, along with new and improved materials for AM, could actually replace or complement traditional manufacturing processes. The development of more robust, accurate, fast, repeatable and cost-effective machines, especially with the PBF process, has reinforced the importance of industrial 3D printing as a true production technology, and today there are opportunities for its intelligent and judicious use as a viable and competitive mass production solution.
However, it’s this change that has also meant that design engineers who are developing products that will be manufactured with AM – or planning to do so – have had to change their approach to design. As I mentioned before, designing for the manufacturing process has always been a thing, whether it’s injection molding, casting, or CNC machining. The point here is that for additive manufacturing, the design rules are a bit different, in fact, they sort of break the mold!
In Part 2, we’ll see how different DfAM is from traditional design-to-manufacturing approaches, the opportunities it brings for product innovation and functionality, and the ability to optimize products in ways that reduce weight and material usage.