3D printing: A new brick in the Great Wall | The Economist
ALTHOUGH it is the weekend, a small factory in the Haidian district of Beijing is hard at work. Eight machines, the biggest the size of a delivery van, are busy making things. Yet the factory, owned by Beijing Longyuan Automated Fabrication System (known as AFS), appears almost deserted. This is because it is using additive-manufacturing machines, popularly known as three-dimensional (3D) printers, which run unattended day and night, seven days a week.
The printers require an occasional visit from a supervisor to top them up with the powdered materials they use as their “inks”, or to remove a completed item, but apart from that they can be left on their own. They build up the objects they are making one layer at a time, as the ink is sintered into place with a laser in a way that creates little waste and can make shapes impossible to achieve using the traditional “subtractive” technology of lathes, milling machines and cutting tools.