"When British supermodel Jourdan Dunn stepped onto the red carpet at the Met Gala Monday night, the crowd rustled with excitement. Dunn was wearing a blood-red gown in the shape of a rose. Lacquered and stiff, the dress looked like freshly poured hard candy. The glossy petals shone in the spotlight, revealing complex layers of folds and velvety swirls that conveyed a vibrant flower in full bloom. But this gown was no ordinary high-fashion affair spun from a confection of silks. Designed by Zac Posen, the dress — 21 plastic petals and the titanium cage holding them in place — was entirely 3D-printed. The petals were printed by Protolabs, a GE Additive manufacturing partner, while GE Additive produced the titanium cage. It took around 250 hours of labor to design and 3D-print the dress — including three days per petal — and another 400 hours to sand and coat the petals with a glossy red automotive paint. “The petals remind me of a Ferrari,” says Eric Utley, an applications engineer at Protolabs. “They look and feel like the panels of a supercar.” The height of fashion innovation, the annual Met Gala raises money for the Metropolitan Museum of Art’s Costume Institute, which houses a global collection of more than 33,000 garments and accessories dating back to the 15th century. Welcoming celebrity stars, young creatives and industry paragons, the gala is one of the most exclusive fashion events in New York. Over the years, the world’s top designers have debuted dresses that glowed from LEDS (another Zac Posen creation) and fiber optics woven into the fabric, gowns spun from recycled plastics, and metallic clothing meant to replicate the shiny look of robots. Entirely 3D-printed, the rose gown worn by Jourdan Dunn at Monday's Met Gala consisted of 21 plastic petals and the titanium cage holding them in place. Top image credit: Patrick Fraser. Above image credit: GE Additive. This week, Posen debuted an entire collection that nudged 3D printing from heavy industry — GE and Protolabs use the technology to produce components for jet engines, gas turbines and medical scanners — to glamour. His rose gown was just the beginning: Actress Nina Dobrev wore a transparent, glasslike bustier dress that resembled a flowing swath of fabric casually draped across her body; it was actually a 3D trompe l’oeil made of plastic. Katie Holmes draped a palm leaf accessory, shimmery from purple pearlescent paint, across her shoulder. Julia Garner wore a vine-inspired leaf-and-berry headpiece — printed in nylon then plated in brass. And Bollywood star Deepika Padukone’s gown sparkled with dozens of 3D-printed “sea urchins” with silver tentacles. Posen also designed and 3D-printed cufflinks in the shape of miniature roses for himself and the men at his table, including actor Andrew Garfield and art dealer Vito Schnabel. For nearly six months, Posen worked with GE Additive’s design engineers and with Protolabs, which specializes in plastic and metal additive prototypes, to realize his designs. Protolabs printed the majority of the garments at its site in North Carolina, and Nina Dobrev’s bustier at its site in Feldkirchen, Germany; GE Additive printed the titanium cage for the rose gown at its Additive Technology Center in Cincinnati. Actress Nina Dobrev wore a transparent, glasslike bustier dress that resembled a flowing swath of fabric casually draped across her body; it was actually a 3D trompe l’oeil made of plastic. Image credit: Patrick Fraser. The vision Posen aimed to capture was of natural objects frozen in motion. He and his team in New York found inspiration from many sources: bouquets of flowers, items from a craft shop and fabric draped on mannequins. They showed the additive engineers at GE these objects, sometimes drafting rough sketches of them. In the case of the rose gown, Posen pinned paper petals to a mannequin to capture the desired shape of the gown. The engineers then created Posen’s ideas using computer-aided design (CAD), working closely with the designer to capture the aesthetic he was looking for and to ensure that the designs would work for additive. “Learning to work with Zac’s team and to speak ‘fashion designer’ was the biggest challenge,” says Sarah Watson, design engineer at GE Additive’s consulting arm, AddWorks. “They were not familiar with 3D modeling, and they are usually very hands-on in their design process.” Typically, Posen starts a design by draping fabric on a mannequin. Here, however, Watson and her team took his initial drapes, inspirational objects, and images and interpreted those to create digital models, which they would share with Posen and his team for feedback — often over FaceTime. “They would tell us things like, ‘It needs more movement and energy!’” she says with a laugh. “We had to learn how to interpret this in CAD.” After Posen offered his approval on the final CAD designs, Protolabs also advised on the designs before starting the printing process, beginning with tiny scaled-down versions. GE Additive and Protolabs had to decide how much plastic to use (shaving the rose petals by the width of a piece of paper to make them thinner made the difference of an entire pound), and what types of photopolymer plastics would be best for each piece. For instance, the bustier (made from Somos Watershed XC 11122 polymer) needed to be completely clear, while the other pieces (made from Accura Xtreme White 200, Accura 60 and Accura 5530 plastics, and Protolabs’ proprietary MicroFine green resin and nylon) needed to be printed from either a stiffer material to hold their shape or a more durable material to resist impact. Bollywood star Deepika Padukone’s gown sparkled with dozens of 3D-printed “sea urchins” with silver tentacles. Image credit: Patrick Fraser. Particularly perplexing was building a bespoke dress for a specific person without being able to do fittings along the way. The engineers had to figure out how the finished pieces, each of which is hard plastic with just a bit of flexibility to it, would fit the model’s measurements. They did this by getting the models’ dimensions through photogrammetry, a process by which the designer walks around a person taking photos and then reconstructs them in 3D. “One of the models casually mentioned that she was planning to lose five pounds before the gala,” Watson says. “We had to build some adjustability into that one!” Because the team knew Posen was such a dynamic designer, too, they took care to give maximum adjustability on the final pieces, within the constraints of printing in hard materials, so he could make adjustments in person. Historically, 3D printing in fashion has been more experimental, tending toward technology demonstrations that emulated science fiction, according to Utley. “This didn’t jive with Zac’s whimsical design language, which is more Cinderella than Terminator,” he says. For Watson’s industry-oriented team, this was initially a challenge. “These organic shapes require very different modeling techniques and CAD tools than heat exchangers or fuel nozzles,” she says. “The beauty of additive is that it enables designers to quickly and efficiently create parts with this level of complexity.” Posen and his team were initially focused on re-creating conventional fabric designs in plastic and metals. As Watson and her team worked on the 3D models, they started to suggest ways to add more intricacy to take advantage of all the design freedom allowed by 3D printing. Many of the designs have features that float away from the body and wouldn’t be possible in fabric. “As we pushed the envelope on complexity, we all started to realize that this collection could be really new and groundbreaking for Zac’s brand, even while it stayed within his classic and elegant design aesthetic,” Watson says. Julia Garner wore a vine-inspired leaf-and-berry headpiece — printed in nylon then plated in brass. Image credit: Patrick Fraser. The result, she says, are pieces that look like sculptures. When Posen first saw one of the shiny rose petals, with its many delicate strata, Watson says watching his ecstatic reaction was “pretty magical.” While the timeline — just a few short months to select concepts, create 3D models, then manufacture and assemble all the pieces — was demanding, Watson says the opportunity was incredible. “This was a really intense design experience,” she says. “But ultimately we were successful in meeting Zac’s vision of capturing natural energy and motion in these pieces. Fabric just can’t do this.”"