“Rapid prototyping” methods of making models of objects from computer files can dramatically cut the time from the drawing board to market. Most such procedures now in use create plastic representations of metal items. But for many manufacturers, that’s not nearly as valuable as being able to rapidly create the piece in metal. Now, researchers at Sandia National Laboratories say they’ve come up with a way to use lasers to fabricate metal parts directly from a computer model, in a matter of hours.In Sandia’s process, a beam is focused to a small spot on the surface of a metal substrate, forming a molten pool. Metal powder injected into the pool solidifies into a bead that protrudes from the surface. Repeating this many times under computer direction builds up the prototype. Ten companies, including 3M, Eastman Kodak and Lockheed Martin, are supporting Sandia’s effort to the tune of $3 million over two years.