Hi, Back in 2017, I posted something about seeing a possible first-ever reference to the idea of 3-D printing in a 1951 issue of Galaxy Science Fiction magazine. I stumbled over an even earlier one tonight... The September, 1941, issue of Astounding Science Fiction magazine has a story called "Elsewhere" by Caleb Saunders (a pseudonym of Robert A. Heinlein). On page 118 we see: [They used] a single general type of machine to manufacture almost anything. They fed into it a plan which Igor called, for want of a better term, the blueprints. It was, in fact, a careful scale model of the device to be manufactured; the machine retooled itself and produced the artifact. A three-dimensional pantograph, Igor called the machine, vaguely and inaccurately. One of them was, at that moment, molding the bodies of fighting planes out. of plastic, all in one piece and in one operation.