That’s the old way. The new method is different, and it involves a laser. New Balance is producing the 3D-printed parts using equipment from a company called Formlabs, and the process starts with a resin that has the consistency of olive or motor oil, says David Lakatos, the chief product officer at Formlabs. Zapping that resin with a blue-light laser spurs it to become a solid, only in the places they’ve hit it. The resin is technically a photopolymer, meaning that the light from the laser sparks the relatively short chains of molecules in it to join up and form longer chains.