“Why aren’t you using additive manufacturing to make your medical devices?” Scott Taylor, Chief Technology Officer at Poly-Med Inc. (Anderson, SC), a supplier of bioresorbable polymers, posed that question to conference attendees at the recent co-located Medical Design & Manufacturing (MD&M) West and PLASTEC West event in Anaheim, CA. Armed with two compelling case studies, he went on to explain why they should.
|Scott Taylor, Chief Technology Officer at Poly-Med Inc.|
“I hear your concerns,” acknowledged Taylor. “The production cost is high, you can’t make enough product, the parts aren’t sufficiently strong or maybe a mechanical feature is preventing you from using additive manufacturing. Put all that together and you’re liable to say, ‘3D printing isn’t ready for prime time,’” said Taylor. He then invited attendees to reconsider that assumption by describing two medical device applications where Poly-Med played a role.
The concept of a device with a mesh component that had added reinforcement around its periphery had been bouncing around for a few years, but conventional manufacturing technologies were unable to satisfactorily produce the part. The material is thermally sensitive, so conventional molding could not be used, and attachment techniques were tricky because the mesh is very delicate, explained Taylor. Attaching the reinforcement material was “basically a hand-work process, requiring multiple manufacturing steps,” said Taylor. There were concerns about quality, because of the manual assembly process, but also scale, “since we didn’t want a roomful of 200 people assembling the product.” Additive manufacturing solved the problem, and it did so by negating two of the oft-cited drawbacks mentioned above: Excessive cost and minimal throughput.
To print the ring-shaped reinforcement, Poly-Med used its Lactoprene 8812 filament, the same material that is used for the mesh itself. “The ring is printed directly onto the mesh,” said Taylor. The heat was localized and the process is quick, resulting in very little heat transfer and a stronger bond than could be achieved using a manual assembly process.
|The next rendezvous for plastics professionals and the medical device supply chain happens in Cleveland, OH, on March 7 and 8, 2018. UBM America’s newest design and manufacturing trade show and conference, Advanced Design & Manufacturing (ADM) Expo showcases five zones—medical manufacturing, plastics, packaging, automation and robotics, and design and manufacturing. A full slate of conference sessions will explore innovations in advanced manufacturing. Go to the ADM Cleveland website to learn more and to register to attend.|
The machine controlled process improved consistency and accuracy, noted Taylor, and by including a cutting process inside the printing box, the company was able to eliminate seven or eight process steps compared with the earlier approach. “The previous process was costly because it was so labor intensive and [additive manufacturing] improved the yield by 80%,” said Taylor. “The potential annual scale is well over one million parts, which fits the application need, in a reasonable amount of floor space of just a few printers.”