FOCUS

When Ford wants to try out a new transmission part, an engineer sends a digital blueprint of the component to a computer, and what happens next once seemed like the stuff of science fiction.

Inside a device about the size of a microwave oven, a plastic, three-dimensional version of the component begins to take shape before your eyes. After scanning the design blueprint, the gadget fuses together a paper-thin layer of plastic powder. It repeats, putting another layer on top, and then thousands more, before binding the material together with lasers.