We’ve been able to design and 3D-print plastic phone cases and toys at home for a decade now. For almost every other consumer product made in a factory, the robots have taken over the heavy lifting. But fashion is still stuck in the 20th century.
Take a typical pair of chinos. Cotton threads are woven on a large loom at a mill somewhere in Asia, then shipped to a dye house, then shipped (usually a great distance) to a garment factory somewhere else in Asia. There, the fabric is laid flat and cut into shapes, with the excess fabric being landfilled, incinerated, or (very rarely) recycled. Underpaid and exploited garment workers hand-sew those pieces of fabric into pants, which are then shipped across the ocean to a fulfillment warehouse or a store near you.
This global apparel supply chain is inefficient and emissions-heavy—an estimated 4 percent of global waste and 2 to 4 percent of greenhouse gas emissions are attributed to fashion production. Brands have to make risky predictions many months in advance about which items will sell, leading them to overorder on a massive scale.
Now, Walmart is piloting a project with the San Francisco Bay area startup Unspun to test whether it can manufacture the retailer’s in-house brand of chinos in the US using a technology called 3D weaving. The experiment is part of a push to nearshore Walmart’s supply chain and cut down on emissions and waste associated with textile production.
While still very much in the prototype phase—the two companies are exploring how to use Unspun's technology to supply pants to Walmart's stores—if successful, this project could upend the way apparel is manufactured on a huge scale. Unspun hopes to eventually deploy 3D weaving micro-factories throughout the United States, so that anyone can order custom and locally made apparel on demand.
Walmart’s investment comes at a time when the failure points of the global apparel supply chain have become painfully evident to both retailers and shoppers as politics, the pandemic, and climate change have all conspired to empty store shelves. A non-comprehensive list of crises includes a tariff war with China, packed ports where hundreds of ships floated offshore waiting to unload, Customs and Border Protection detaining apparel shipments because of suspected forced labor, and epic flooding that destroyed cotton crops in Pakistan.
Many retailers, after initially canceling their orders as stores shut down in 2020, struggled to restock, and then overordered to compensate. By the end of 2022, retailers were holding a record $732 billion in merchandise. In 2024 uncertainty continues to reign—a prolonged drought has cut the number of ships that can cross the Panama Canal, and ships are being attacked in the Red Sea, the main throughway to the Suez Canal, by Yemeni Houthis in support of Iran and Palestine. Fashion brands who want to keep up with trends and get products to customers fast are booking out air freight, pushing emissions higher.
Nimble, Local Manufacturing
Unspun cofounder Beth Esponnette became disillusioned working as a designer for outdoor and sports apparel companies in the early 2010s. She was privy to one meeting where a brand discussed whether to landfill, incinerate, or donate a cache of unsold tents it had ordered many months before. “It was just so frustrating to sit in that meeting. Like why did we make that stuff? No one wants it,” she says. And it seemed antithetical to the spirit of an outdoor brand and its nature-loving customers.
So she went back to Stanford University, where she met Walden Lam, who would become Unspun’s CEO and cofounder. She brought Kevin Martin, who has a history in robotics and engineering, onboard as the third cofounder in 2016 to oversee the development of 3D weaving machines.
The difference between knitting and weaving is the difference between what you see in a sweater versus what you see in a T-shirt. But it’s also about speed and efficiency. 3D knitting machines already exist, but they move slowly, with a shuttle pulling one yarn back and forth, similar to a 3D printing machine drawing an object with a single line of extruded plastic. Creating a pair of pants with a 3D knitting machine takes about two hours.
3D weaving is much faster. “It has thousands of yarns coming into it, so we can make the same clothes in like 10 minutes,” says Unspun CTO Martin. Named after a star in Chinese mythology that represents a weaver girl, the company’s Vega machine outputs tubes of fabric that can be joined together into garments like pants and shirts. For now, Unspun is focusing on pants, because smaller tubes mean smaller machines, and a pant leg is smaller than a torso.
During a tour of Unspun’s micro-factory, Martin switches one Vega machine on to demonstrate. The shuttle is greyhound-fast, whipping around a small circular track in a sinusoidal pattern. A tube of fabric flows out of the bottom. After 10 seconds of it whirring, he says, “Just so you know, that would have been 40 minutes on a knitting machine.”
Unspun is attacking the problem of fashion waste and emissions from several angles. The typical cut-and-sew process, according to Unspun, on average trashes 14 percent of the material. 3D weaving produces only 3 percent cutting waste. This method also cuts down on emissions spent landfilling or incinerating surplus fabric.
The team has also developed a separate app that remotely scans a customer’s body to design a custom-fit pair of pants. You can use it today to order custom jeans, though they are cut and sewn in the traditional way—Unspun hasn’t yet bolted the software onto the machines. Right now, machine operators choose Vega’s settings to create the product. Unspun is working on software that would translate a design into direct commands to Vega, so retailers or fashion brands could feed their virtual creations into the machine and then get a wearable prototype in minutes.
Unspun’s vision is to one day have hundreds of Vega machines across the US. A customer of one of Unspun’s retail clients would get a body scan, choose the type of garment they want, and as soon as they click purchase, send the design to the nearest Vega machine, which would output their order the same day. A custom fit means fewer returns, and because many returns are sent to the landfill or incinerated, that means waste and emissions are reduced even more.
Walmart does have a successful program to curb its suppliers’ emissions that involves energy efficiency and renewable energy projects at factories. But when Walmart VP of sourcing Kyle Carlyle visited Unspun’s micro-factory last year, he was struck first by the giant American flag hanging above the machines. In 2021 Walmart announced that it was committing $350 billion (in addition to a 2013 $250 billion commitment) to support US suppliers. The move wasn’t just good marketing—in a 2019 survey, 85 percent of its customers said it was important that Walmart carry American-made products—but also one that would help future-proof Walmart’s business.
“My team takes care of what Walmart calls surety of supply—essentially, building in resilience to how we source,” he says. He’s talking about a supply chain that can absorb shocks from natural disasters, pandemics, political unrest, and the like, and still deliver goods quickly enough to keep up with trends.
3D Thinking
The first step to making 3D woven chinos is completely rethinking how they’re designed. Typically, a designer will create a 2D tech pack with the cut shapes, and then select the fabric for look, feel, and performance based on swatches. But the machines require the selection of the individual threads going into the machine, plus envisioning the whole design as a series of 3D tubes. Knitwear designers are used to this mode of thinking. Designers of woven products—T-shirts, jeans, and pants—are not. “The designers are often getting to think about designing the fabric for the first time, rather than just the product made for that fabric,” Unspun’s Martin says.
The possibilities afforded by 3D weaving are expansive. In September, Unspun worked with the designer label Eckhaus Latta to create several looks for New York Fashion Week, including shimmery plastic-tape-and-cotton pants. In the glass-walled showroom, Martin pulls another example off the rack: pants that looked like Chanel bouclé, but on acid, with a psychedelic pattern you could fall right into. Someday, a designer could upload an image and have it woven right into the fabric.
But for now, the goal is more mundane: ensuring that when Average Joe walks into his local Walmart, he can find a pair of work pants in his favorite style and the right size. If it has a little American flag label, well, that’s just a bonus.
