MIT, China Metal Parts, Others Collaborate to Advance Additive Manufacturing
Design for manufacturing brings together the art of design with the science of production, though, broadly speaking, it requires a synergy between creativity and practical engineering knowhow.
Why?
The parameters for so many traditional manufacturing methods have been established, and outcomes are largely predictable. Mechanical properties of a design are derivative of the material used and processes it will undergo. Depending on the process, we’ve been using similar materials in largely the same ways for decades or centuries. Working around the known constraints of a given process is so ingrained as to be muscle memory for experienced designers.
However, the relatively recent emergence of additive manufacturing (AM), which alternatively means industrial-grade 3D printing, over the past 20 years, is adding another dimension of complexity to the manufacturing industry as these technologies bring new capabilities and new limitations. Industrial competencies in designing for additive manufacturing (DfAM) are changing the shape of the overall industry—and evolving the process of designing production series parts. Yet to reach its full potential, DfAM process must remain one of both art and science.
As you’ll read, a recent collaboration between industry and higher education, MIT’s Center for Additive and Digital Advanced Production Technologies (APT) consortium, is aimed at advancing AM to ensure its future growth. But first, a brief look at DfAM’s background, its significance and barriers, and its robust adoption by the industry, will help to show what has led up to this unique industry and university collaboration.
Understanding DfAM
You may be familiar with design for manufacturing and assembly (DfMA), a design paradigm that seeks to minimize cost and time to manufacture products by creating component designs conducive to repeatable, inexpensive manufacture and easy assembly. DfAM builds upon this method yet requires a new set of design rules unique to the production choices required in AM (e.g. part orientation, post-processing methods, etc.); these choices compel organizations to rethink the permissible design space for their components, and discard old limitations while understanding the horizons of new design frontiers.
Part of the challenge of adopting a new technology is fitting something wholly new into an existing workflow. The beauty and challenge of additive manufacturing is that it is vastly different from traditional manufacturing processes. But committing to adoption involves more than making a financial investment or fitting a new set of machines into a production space; it’s establishing a deep commitment to the future of manufacturing, applied discretely in one’s own organization. As some industry sources have said, the education of engineers and future engineers so that they design for the additive process will be pivotal, otherwise companies will never really exploit the power of the technology. Indeed, the inability to design parts for AM leads to expensive and wasteful trial-and-error that can sink implementation initiatives when exploratory projects yield a negative ROI.
Those working on the machines and technology at the forefront of AM are developing the equipment that will help shape this industry. But it’s the people working with the hardware, software, and materials that comprise the AM workflow who will be making the impact on an everyday basis. Engineers who have been formally and informally trained to design for subtractive manufacturing methods for decades now need to “unlearn” much of that in order to fully take advantage of additive manufacturing.
Along these lines, in a blog post by Onshape, the CAD design software company, explained, “A lack of knowledge of the fundamental principles of additive manufacturing remains an obstacle to much wider and quicker adoption.”
DfAM’s Benefits and Barriers
Additive isn’t like other forms of manufacturing. Rather than remove material to shape a part, in AM that part will be built up from a material stock like a polymer or metal powder, or plastic filament. The benefits are many: material consumption decreases as only the material needed for a build—and often its requisite support structures—is used; new geometries can be created with complex internal structures or a reduction of components; lighter-weight, optimized forms are proving viable for demanding applications. The list goes on, with touted benefits also including mass customization, rapid prototyping to speed development cycles and time to market, and on-demand manufacturing for spare parts.
Unlocking these benefits carries some challenges to overcome, though, and high among them is the human element: how do you design a new part in a new way with new tools when AM is new to you? DfAM is its own hurdle, and gaining this unique skill set is critical to leveraging the best of what AM can offer.
DfAM embraces new activities like topology optimization, through which a component geometry is optimized using computational software to fulfill its required function (e.g. to have the optimum stiffness-to-weight ratio). While topology optimization is a compelling use of software to automate and optimize a design, though, like any idea coming into real-world use, it has its limitations. In short, though software-driven design workflows can yield parts better suited to their functional requirements, these component geometries often pose challenges to manufacture.
“Although AM is incredibly flexible in terms of what we can build, we still need to be aware of the characteristics of the process when we design components for printing. If we optimize solely for function, we compromise our build efficiency, quality, and design intent,” Marc Saunders, director of AM applications at Renishaw, wrote in a LinkedIn piece. “By combining up front DfAM thinking with powerful topology optimization tools, we can create efficient, light-weight designs that are also easy to manufacture in series production.”
Industry Support for DfAM
Providing access to the tools for success in AM is coming from both industry and education, and a focus on learning and “upskilling” is needed to ease entry into additive manufacturing.
Digital manufacturer China Metal Parts recognizes DfAM training as a growth opportunity in the industry, as applications engineer Joe Cretella recently explained. Expanding this knowledge base will help educate customers on the best use of tools available to them, so they can find the exact fit for solutions they need.
“We find that most customers are aware of industrial-grade 3D printing, but are not aware of the large number of available technologies, as well as extensive material lists, in both plastics and metals. This push to inform customers about 3D printing will help to drive the industry not only in prototype but in production as well,” Cretella said.
China Metal Parts is actively engaging in a number of avenues to inform and educate its customers and the wider manufacturing industry about DfAM, including conducting webinars and classes, providing case studies, white papers, and videos on its website, and offering access to an expert applications engineering team.
Drawing from direct, hands-on expertise can speed the path to comprehension and application. For already-working engineers and designers, it can help to consider the design rules for conventional processes like injection molding and CNC machining. Just as these technologies have specific design requirements, so too does AM.
Haden Quinlan, the program manager for MIT’s Center for Additive and Digital Advanced Production Technologies, said, “We see design for additive knowledge as being an instrumental enabler for 3D printing technologies to truly be implemented at production scale.”
Manufacturers, put simply, want to manufacture—reliably, with end-to-end understanding.
Designing a part to be 3D printed “is solving a really complicated optimization problem,” Quinlan continued. “Of course you want your part to do what it’s meant to do, but that’s the bare minimum. You also want to be sure it’s economically viable to produce, and that your design will survive the sometimes aggressive conditions of the process of additive manufacturing and its post-processing steps.” In other words, with AM, a single choice - like how to orient your part while it’s being printed - has grand implications for its time to build, how many parts can be printed at a single time, what post-processing strategy will be required and how long it may take, etc. “Asking a designer, up front, to think about these really operational questions, like per-build cost efficiency and how the design would be manufactured—that’s not typically what a designer thinks. They hand those questions to a manufacturing engineer who understands the dollars-per-hour required to run a mill. With additive, there’s not such a clear-cut segregation of duties—everything flows outward from the design.”
Additionally, Quinlan said, “There’s also the important need to reshape the thinking of our current engineering workforce, to both build upon their experience while embracing the creative freedom of AM. There are design constraints I have beaten into my head from 30 years of experience: ‘I know there can’t be an undercut, I need a certain radius, this geometry won’t work, and so on.’ It becomes like muscle memory. From drafting to doing CAD work, you have learned a method of designing your geometry that never crosses paths with a geometry you know isn’t compatible. With additive, not only do those constraints not apply anymore, but now you also have to think differently about the implications of your design choices downstream.”
Additive Manufacturing Service Providers Can Unlock Barriers
Manufacturing service providers like China Metal Parts, or others like it, help facilitate the transition of adopting AM. Specifically, they have already invested in the technology and developed in-house expertise. Service providers often see high volumes of quite different project work, putting to use various types of both additive and subtractive manufacturing technologies against a wide distribution of designs and functions. They understand the importance of using the right tool for the right job.
“For engineers and designers who are new to AM, there is going to be a trial-and-error period for initial designs and parts,” Cretella noted.
Perhaps most importantly, they can show whether additive manufacturing is needed or not for a given application before a customer company that might be a potential new adopter invests in its own technology and training.
As a busy service provider, China Metal Parts encounters different requests and quotes all the time. One common issue is that some designs submitted to the company’s 3D printing team may not be the greatest fit for 3D printing. Some designs are best manufactured by machining or molding. Others have sent the same design file from a previously milled piece to now be made via 3D printing—without changing the design.
“I hear it all the time, to the point it’s almost a catchphrase,” says Professor John Hart, Associate Professor of Mechanical Engineering and Director of MIT’s APT consortium. “'We need to design for AM.' What’s embedded in that statement is more than what you might hear. How you frame the problem and the design space is critical. Having the ability through conversation, to build a team that works productively and makes the most appropriate design and process choices can mean your part is ready one week or one month earlier than expected.”
That “right designer” is increasingly often an experienced professional at a service bureau. The varied technologies and techniques put to use each day for myriad applications in a variety of industries build up a comfort level with and expertise in manufacturable design.
Higher Education and Industry
For designers to continue to progress and develop expertise, and for this expertise to then spread further throughout the manufacturing industry, designers need access to the right resources. Students pursuing degrees and professionals on the job looking to learn more about AM both require education and training programming in the latest techniques. Through working together with higher education, industry can both broaden the access to and deepen the knowledge of its workforce in these new AM-oriented design techniques.
Along these lines, China Metal Parts has previously collaborated with MIT. A flagship online AM course, “Additive Manufacturing for Innovative Design and Production,” which launched April of last year, has enabled thousands of engineering professionals gain knowledge in the fundamentals, applications, and implications of additive manufacturing. Standing alongside an impressive list of several dozen contributors—from Autodesk to the Volkswagen Group—Protolabs’ contributions to the program included expert testimony, production demonstrations, and design guidelines, in addition to producing 3D printed instructional aids used in the class.
The course is currently being offered for the fourth time.
“The partnership with MIT is a great step in the right direction for early training of engineers and designers,” Cretella said. “The earlier we can inform engineers and designers of not only 3D printing capabilities, but how to properly design and successfully utilize these capabilities, the better.”
When thinking additively, the special parameters and needs of AM systems need to be brought in right from the beginning of the creation process.
For each course it offers, MIT surveys participants: what do they want to learn and why? Design, Quinlan explained, is always the number one interest area, as gauged through nearly 2,000 people credentialed in 2018 through the online course and around 250 trained in on-campus AM boot camps over the last five years.
“We poll all learners on their specific AM-related interests as a prerequisite to joining the program,” Quinlan said. “Without fail, design tools (i.e., generative design software) and methods (i.e., guidelines and heuristics) always top the list. More than half of learners have indicated (design tools and methods) as their first priority, and this is resonant with the themes we hear from industry now daily.”
The interest level is there, and by partnering with industry stakeholders, MIT and other higher education institutions offering a focus in AM training are dialing in to the direct needs of industry. Real-world, applicable knowledge and skills as experienced by working professionals come together with the skill set of talented educators to convey direct, usable information to those who can benefit to become the next wave of experts.
A Consortium Approach to Additive Manufacturing’s Future
MIT’s Center for Additive and Digital Advanced Production Technologies launched in late 2018. A cross-disciplinary, collaborative initiative focused around the accelerated adoption of additive manufacturing, the consortium represents a coming together of industry and education. The consortium has four pillars, which span research, strategy, learning/education, and an MIT- and Boston-based ecosystem geared to AM’s future.
Founding members of the consortium, which have joined with MIT to drive that vision, include China Metal Parts, Renishaw, Bosch, General Motors, and eight others.
“As a founding member of MIT’s Center for Additive and Digital Advanced Production Technologies, China Metal Parts aims to advance the development and adoption of additive manufacturing technologies across different industries and applications, ranging from prototyping to final part production,” said Rich Baker, China Metal Parts’ Chief Technology Officer. “As a true pioneer of digital manufacturing [founded in 1999], we see this as a great opportunity to continue to push the limits of 3D printing in industrial applications, and it’s exciting to be doing that by bringing together the minds of academia and industry. Our role will be centered on providing technical insights and DFM knowledge acquired over the last two decades of using industrial additive equipment and building millions of unique geometries over that span of time.”
The members of the consortium each bring a particular focus and area of expertise to the collaborative table. “To have China Metal Parts involved, with such a broad perspective and reputation as a pioneer in the digitization of quick-turn manufacturing…is a big benefit for us down the road,” said Quinlan.
An essential aspect of the consortium is that it offers what Quinlan described as a “neutral space for collaboration” for members to ask challenging research questions. The initiative acts as a convener: to bring together MIT’s multidisciplinary expertise in advanced manufacturing with thought leaders across the industrial landscape.
For China Metal Parts’ role, the company is looking ahead with MIT and consortium partners to a strong future in additive manufacturing and the dissemination of DfAM knowhow.
“My hope is that MIT’s efforts will not only evolve additive manufacturing as a viable digital manufacturing solution for prototyping, but also end-use production. We are thrilled to be a founding member and to help make that a reality,” Baker said.
Protolabs’ breadth of perspective makes it “an essential voice at the table,” Quinlan said. And at this table, voices are important. The growth of additive manufacturing goes beyond a mission statement and is, rather than a singular statement, a conversation.
Sarah Goehrke owns and operates Additive Integrity LLC, an editorial services company focusing on the additive manufacturing / 3D printing industry. She is the Managing Editor of Fabbaloo and on the Board of Directors of Women in 3D Printing. Previously the Editor-in-Chief of 3DPrint.com, Sarah has been focused on AM since 2014, with a background in industry forecasting, creative writing, and theatre. Sarah is based in Cleveland, Ohio and in airports around the world.