Earlier this year I printed some 3D objects at Shapeways. 3D printing is a fairly new technology, with lots of methodologies and applications. In its simplest form, it’s just like regular inkjet printing, but instead of the print head laying down a drop of ink, it lays down a blob of plastic, and once the first layer is done, the print head starts printing plastic on top of the plastic. After several hundred layers, a 3D object is finished, and can be assembled into a UAV, or a rifle reciever, or a magazine.
Different printers can print different types of resin, plastic, ceramic, and even metal. Some printers have an ink nozzle right next to the media nozzle, so it can paint objects in full color while printing. Other dual-head printers can print a rigid plastic and soft rubber at the same time, or ABS and wax. This is useful for objects with a lot of non-touching moving parts, like gears. The gears and axles can be printed in hard plastic, supported by the printed wax until the object is done and the wax can be melted or crumbled out.
There are even experiments in printing blood vessels and human organs, cell by cell, custom designed for transplant surgeries. As the printers get more sophisticated, they can do more things. Researchers are building machines than can print optics and electronic sensors directly into objects during printing. One of the great advantages of this system is that the cost is the same to print one object as it is to print a thousand. Mass production of injection molded plastic still might be cheaper in the long run, but there’s no setup cost to print a single custom product.