Faster machines, better materials and improved software have made additive manufacturing increasingly viable for mass production. With the majority of technical barriers eliminated, the next challenge is understanding how to leverage additive’s strengths on the production line.
Serialization—using additive to print or deliver parts on demand—can significantly decrease the time between order and delivery, allowing production to quickly pivot from one material to another or shift to a new product entirely. It combines the best features of additive—utilizing new materials and cutting waste while producing large quantities of identical components at a consistently high quality—with increased supply chain resilience to respond to shortages and delays in real time.
As the industry works to rebound from the global supply chain crisis, serialized additive manufacturing offers something new: a responsive, cost-effective way to retain more control over the production of parts.
Designing for Additive
That said, while the potential of serialization is clear, there are still barriers to adoption. Implementing additive on a large scale will require manufacturers to invest in equipment and training. While 3D printing can ultimately unlock cost savings, this initial obstacle could be a deterrent, especially among small and mid-size shops.
Additive also demands a different approach to design, something that many engineers are only beginning to comprehend. 3D printing machines can produce complex parts at reduced weight and cost. However, the additive design process differs from that of traditional manufacturing techniques such as forging or casting. Designers need to work around gaps in the capabilities of additive — for instance, by avoiding steep overhangs. Since 3D printing adds matter layer by layer, designs with slopes that exceed a certain angle are vulnerable to gravity. If left unchecked, this can undermine the entire product.
In addition, the limited build area of 3D printing machines lends itself to small-footprint pieces. Designs that stack multiple small parts can optimize cycle time and reduce waste.
To prepare for serialization, manufacturers may need to revise the specifications of components previously produced with methods like molding and milling to ensure they will remain stable in the printing process.
Product designers created the design for additive manufacturing (DfAM) guidelines to address these parameters. DfAM allows engineers to produce — or redesign — product blueprints that play to the strengths of AM, maximizing the use of the technology and minimizing issues during production.
For companies used to designing for traditional methods, consulting with a specialist who understands how designs should be modified for AM can be a helpful first step. An engineer familiar with DfAM principles can help manufacturers achieve the best structural and material performance while bypassing design pitfalls.
Since the fundamentals of 3D printing remain the same regardless of scale, experimenting with designs and processes on a simple, cheap printer can also help engineers build proficiency before tackling bigger print series.
Testing the Waters
In recent years, Trumpf has observed increased demand for additive technology that can be integrated into the production line. The company recently tested the efficacy of laser powder bed fusion (LPBF) on a serial run — a case study that will be presented at RAPID + TCT 2023.
One of the most common methods for printing metal, LPBF uses a high-power laser beam to fuse layers of powdered material. Makers can use LPBF to work with various metals, including stainless steel, titanium, aluminum and copper. Trumpf engineers used LPBF to produce high-performance titanium bicycle parts, including hydraulic brakes, which are typically made of aluminum.
The outcomes were encouraging. LPBF allowed the team to trim costs and lead time. Furthermore, the resulting pieces were more durable and lightweight than on-market alternatives. This is because the process used titanium, an extremely strong metal that is typically inaccessible due to the expense, time and difficulty associated with machining it.
A Holistic Approach
Graduating from custom parts and prototypes to serialization will require an approach that considers the scope of AM at every stage of the process — from design to finishing.
For suppliers looking to integrate 3D printing into their production lines, design is likely the biggest hurdle to overcome. Working with a DfAM expert can help engineers adapt to the new design parameters imposed by AM — and identify strengths of the process that can improve the performance of parts.
Manufacturers need to consider post-production, too. In the case of LPBF, workers must first separate components from the substrate plate and then treat them to enhance the surface quality. Fortunately, machine suppliers are now devising ways to scale post-production, such as using tumbling machines to smooth printed plastic and metal parts.
By considering the complete production chain, companies can ensure they have the equipment, time and money to facilitate the entire process from the outset.
Investing Early
As companies continue to grapple with the impact of the pandemic on supply chains, serialized additive manufacturing could provide a unique way to future-proof production. It can also help manufacturers branch into new materials, improve processes and boost the flexibility of their facilities.
For Trumpf, the serial production of titanium bike parts demonstrated the untapped potential of additive. While the titanium powder used in LPBF is still expensive, the process is substantially more affordable than milling, opening up new possibilities for a range of applications.
As the technology becomes more sophisticated and the quality of raw materials increases, 3D printing will become progressively more lucrative. To bring additive to scale, companies should begin testing equipment and reframing their designs and processes to meet the needs of a new set of production standards.
The manufacturers that invest in serialization early will be the first to reap the rewards: from new materials to faster, cheaper and more resilient production lines.
Christian Lengwenat is an application engineer for metal 3D Printing at Trumpf, one of the world's largest providers of machine tools. In this role, he provides technical consulting for process, machines and design for additive manufacturing (DfAM) and supports process development for metal additive manufacturing on TruPrint Machines. He is presenting on metal 3D printing in bicycles at the RAPID + TCT conference this May in Chicago.
