Comparing the cool factor of medical device components to Robert Downey Jr.’s gleaming armor in the film Iron Man 2 is…well…tough. But compare the work of many medical device design teams to Iron Man’s special effects crew and there’s a kindred link: three-dimensional (3D) printing and rapid prototyping.

Fig. 1 – Popularity of 3D printers in the medical/dental world (Credit: Wohlers Associates, Inc.)

“To create an actual (Iron Man) suit… was insanely complicated,” said Jason Lopes, lead systems engineer at Hollywood special effects studio Legacy Effects during a Bloomberg Television interview. “We used to sculpt them (prototypes), but with today’s demands…there’s no way to stay viable without 3D technology.” For the elaborate pieces in Iron Man’s armor, Lopes and his team used 3D printing to “kick out changes overnight and physically put things in people’s hands.”

What’s the Connection?

Like Lopes and his team, designers and engineers at some progressive medical device firms have replaced traditional tooling methods with 3D printing and rapid prototyping. 3D printing—also called additive layer manufacturing—is the tool; rapid prototyping is the method. Combined, they create a swift, collaborative process that eliminates weeks of work, significantly reduces costs, improves customer relations, and hastens the road to full-scale production.

The popularity of 3D printers in the medical/dental world continues to accelerate, according to Wohlers Associates, Inc., Fort Collins, CO, a 3D consulting firm. Worldwide spending on 3D printers, after-market products, and more exceeded $3 billion in all industries, with medical/dental fields among the Top 4 at $411 million. (See Figure 1)

Slow and Steady: Traditional Prototype Design Losing the Race

Time consuming and costly machining, casting, and molding are the go-to methods many medical designers still use to build prototypes. It can be a cumbersome process. When OEMs, doctors, nurses, and other medical end-users assess a prototype, they most likely will request changes. Then it’s back to the lab for the designers and engineers, who can spend weeks re-designing, casting, and molding before presenting version 2. Then more feedback, and round 3. And so on.

3D printing and rapid prototyping are to the product design world what the microwave oven was to cooking: a bold leap in efficiency.

To print an object, a designer first creates a 3D computer-aided design (CAD) model. Next, CAD software slices the model into extremely thin cross-sections on the computer. Using the CAD-generated, ultra-thin cross-sections as a roadmap, the 3D printer extrudes material back and forth starting at the bottom and working its way up. The process continues until the object is finished. The base where printing occurs can vary from several inches on a desktop model to several feet on multi-ton, production-scale printers.

Today’s 3D printers, which can range from a few hundred dollars to $300,000, can accommodate a variety of materials, including ABS plastic, PLA, polyamide (nylon), glass filled polyamide, stereolithography (SLA) materials, such as epoxy resins, silver, titanium, steel, wax, photopolymers, and polycarbonate.

Real World Examples

Take the 3D prototype of a dual-flow needleless blood collection system. Produced in 2014 by product development company Worrell, Minneapolis, MN, for MedTG LLC, Brazil, IN, 3D prototype costs were 70 percent less than traditional tooling and production time was cut by 95 percent. “We are able to create a prototype for a fraction of the cost and in a matter of days compared to the eight-week lead time associated with traditional tooling processes,” said CEO Kai Worrell.

Device engineer Alex Berry of Sutrue Ltd., Chelmsford, UK, shared his story in a 3D Printer World article. The company needed a prototype of Sutrue’s new automated medical stitching device. “It was about six months of work in a week. It wasn’t just faster, it was cheaper, too. We had one set of components that had cost $160. With our own printer, it came down to $5.37,” he said.

Seeing Is Believing

Fig. 2 – No need for Tony Stark’s technical resources with the increased efficiencies and cost savings 3D printing brings to rapid prototyping of medical devices.

Like the special-effects team that hastily revised Iron Man’s armor after getting feedback from higher-ups, medical device teams use rapid prototyping to easily and inexpensively get end-user opinions. They then can swiftly make the requested modifications, present an updated version, and eventually secure approval on a final design before investing thousands of dollars in an injection-mold tool. The key is listening, listening, and more listening. (See Figure 2)

Doctors, nurses, and other medical end-users who can touch, see, and deliberate the first 3D prototype with the designers are likely to share more in-depth feedback than by viewing a 2D or 3D drawing.

“A customer will say, ‘You created it just as I described, but now that I see it, I think we need to change X, Y, or Z,” said Brian McLaughlin of Orchid Design, Shelton, CT, a division of Orchid Orthopedic Solutions, a customer of Stratasys Ltd., Minneapolis, MN, which provides 3D printing and additive manufacturing products.

The human factor is a crucial element in medical device design. When done right, the collaborative approach in rapid prototyping focuses on user-centered design.

“When it comes to device design, human factors focus on product usability, or how easily the intended user population can operate the device in the intended use environment,” wrote Natalie Abts and Andy Achaudt from the National Center for Human Factors in Healthcare at MedStar Health, Columbia, MD. “Designers should employ a user-centered approach that focuses on the wants and needs of the end users. This is especially important in healthcare because, unlike in many other industries, the user and customer are not always the same person.” They stressed that while a nurse or physician is likely to be the end user, hospital buyers often make the purchasing decision.

“Incorporating a user-centered approach early and often in the design process can lead to great benefits both financially and in terms of safety,” they added. “Eighty-five percent of the usability problems with a prototype can be detected by conducting small-scale formative tests with five to six users.”

Mike Moussa, a professional engineer and founder of 3D printing company PartSnap, Irving, TX, concurs. He told Professional Engineering magazine, “You can rapidly design something and get it into your hands relatively inexpensively and test it and play with it and tweak the design, print a new part, and iterate again.”

Perfect for Prototypes; Not Full-Scale Production

3D printing is becoming the go-to tool for producing prototypes and small numbers of medical devices. But using 3D printers to manufacture immense quantities is likely far off. In today’s competitive manufacturing world, a few hours or days to produce a thousand devices on a 3D printer is not economically feasible.

“Currently, 3D printing is slow; so slow that it would take you days to print a large product,” said TJ McCue, a technology consultant who travelled the United States for eight months exploring 3D printing, scanning, and design. “Many of the print beds, often less than one cubic foot, are built to print small items and even those take a few hours. Compared to traditional means of manufacturing that crank out products by the minute, 3D printing is not yet fast enough for our mobile, want-it-now world,” he stated in a 2014 Forbes article.

But the environment is changing. The US government is taking the lead on creating a larger, faster 3D printer. In February 2014, the Department of Energy’s Oak Ridge National Laboratory (ORNL) announced that it is teaming with a printer manufacturer to build a system 200 to 500 times faster and capable of printing polymer components 10 times larger than today’s common additive machines. “The project could introduce significant new capabilities to the US tooling sector, which, in turn, supports a wide range of industries,” ORNL stated in a press release.

Industry Acceptance

A December 2014 article by Canadian investment firm Health Technology Exchange noted that challenges remain for the medical sector to fully embrace 3D printing, with product development being the biggest challenge. “If proponents of the technology can expedite the product development cycle and convince regulators to catch up to the capabilities of modern manufacturing, it will go a long way toward ensuring the full potential of 3D printing technology is embraced by the healthcare sector.”

Even with that challenge, 3D printing in the medical device field is definitely on the upswing. Terry Wohlers, CEO of Wohlers Associates, noted that competitive pressure is a driving force for this growth. “When a device manufacturer sees other companies using the technology, they start saying, ‘Should we be looking at this? Monitoring it?’ We’re seeing this across all industries, not just medical.”

Wohlers’s advice before buying: Try it first. Attend 3D printer conferences to learn more. Work with service providers. “Don’t get in too big of a hurry. Pace yourself.”

Back to Tinsel Town. While much of Hollywood is waking up to 3D printing technology, Iron Man 2’s Jason Lopes and his team have embraced it. He told CNET that producers are starting to take notice. “We walk them over and show them and blow them out of the water.”

3D printing of medical device prototypes is a spot-on example of what Tony Stark (aka Iron Man) meant about the power of technology advances: “Please... It’s not about me. It’s not about...you... It’s not even about us, it’s about legacy. It’s about what we choose to leave behind for future generations.”

This article was written by Marcus Kincaid, Senior Applications Engineer, Nordson MEDICAL, Fort Collins, CO. For more information, Click Here . MD&M East, Booth 2015