Source - Economist, July 1, 2017: "3D printers will change manufacturing"
From the article: "3 D printing has become a popular way of producing one-off prototypes, because changes are more easily and cheaply made by tweaking a 3D printer’s software than by resetting lots of tools in a factory. That means the technology is ideal for low-volume production, such as turning out craft items like jewelry, or for customizing products, such as prosthetics. Dental crowns and hearing-aid buds are already being made by the million with 3D printers. Because it deposits material only where it is needed, the technology is also good at making lightweight and complex shapes for high-value products ranging from aircraft to racing cars. But skeptics say that 3D printers are too slow and too expensive—it can take two days to create a complex object (typical rates are one or two cubic inches per hour)."
Adidas has started to use a remarkable form of it called “digital light synthesis” to produce the soles of shoes, pulling them fully formed from a vat of liquid polymer. The technique will be used in a couple of new and highly automated factories in Germany and America to bring 1m pairs of shoes annually to market much more quickly than by conventional processes. Also, a new technique called bound-metal deposition has the potential to change the economics of metal printing, too, by building objects at a rate of 500 cubic inches an hour."