This Company Does 3D Printing at a Speed No One Else Can Match

In this gleaming lab in Redwood City, Calif., the first thing you notice is the burnt smell in the air. The next thing you notice is the whirring noise, from the machinery at the center of the lab cleaning objects pulled from humming rows of 5-foot-long cylindrical printers. They’re turning sludgy trays of gooey resin into caramel-colored shoe soles, valves, and prototype knee replacements.

This is Carbon, the first company in the $4 billion 3D-printing industry to offer a serious—and seriously fast—alternative to conventional injection molds. Using new materials, hardware, and software, Carbon’s printer, the M1, fires UV light at its syrupy resins to produce prototypes and production parts that can be more bouncy, stiff, tough, or heat-resistant than rival products, printing at speeds competitors can’t match. Co-founder and Chief Executive Officer Joseph DeSimone gets a little flowery when the knees come out. “We don’t print,” he says. “We grow.”