THE industrial revolution of the late 18th century made possible the mass production of goods, thereby creating economies of scale which changed the economy—and society—in ways that nobody could have imagined at the time.
Now a new manufacturing technology has emerged which does the opposite. Three-dimensional printing makes it as cheap to create single items as it is to produce thousands and thus undermines economies of scale. It may have as profound an impact on the world as the coming of the factory did.
It works like this. First you call up a blueprint on your computer screen and tinker with its shape and colour where necessary. Then you press print. A machine nearby whirrs into life and builds up the object gradually, either by depositing material from a nozzle, or by selectively solidifying a thin layer of plastic or metal dust using tiny drops of glue or a tightly focused beam. Products are thus built up by progressively adding material, one layer at a time: hence the technology’s other name, additive manufacturing. Eventually the object in question—a spare part for your car, a lampshade, a violin—pops out. The beauty of the technology is that it does not need to happen in a factory. Small items can be made by a machine like a desktop printer, in the corner of an office, a shop or even a house; big items—bicycle frames, panels for cars, aircraft parts—need a larger machine, and a bit more space.
At the moment the process is possible only with certain materials (plastics, resins and metals) and with a precision of around a tenth of a millimetre. As with computing in the late 1970s, it is currently the preserve of hobbyists and workers in a few academic and industrial niches. But like computing before it, 3D printing is spreading fast as the technology improves and costs fall. A basic 3D printer, also known as a fabricator or “fabber”, now costs less than a laser printer did in 1985.
Just press print
The additive approach to manufacturing has several big advantages over the conventional one. It cuts costs by getting rid of production lines. It reduces waste enormously, requiring as little as one-tenth of the amount of material. It allows the creation of parts in shapes that conventional techniques cannot achieve, resulting in new, much more efficient designs in aircraft wings or heat exchangers, for example. It enables the production of a single item quickly and cheaply—and then another one after the design has been refined.
For many years 3D printers were used in this way for prototyping, mainly in the aerospace, medical and automotive industries. Once a design was finalised, a production line would be set up and parts would be manufactured and assembled using conventional methods. But 3D printing has now improved to the point that it is starting to be used to produce the finished items themselves (see article). It is already competitive with plastic injection-moulding for runs of around 1,000 items, and this figure will rise as the technology matures. And because each item is created individually, rather than from a single mould, each can be made slightly differently at almost no extra cost. Mass production could, in short, give way to mass customisation for all kinds of products, from shoes to spectacles to kitchenware.
By reducing the barriers to entry for manufacturing, 3D printing should also promote innovation. If you can design a shape on a computer, you can turn it into an object. You can print a dozen, see if there is a market for them, and print 50 more if there is, modifying the design using feedback from early users. This will be a boon to inventors and start-ups, because trying out new products will become less risky and expensive. And just as open-source programmers collaborate by sharing software code, engineers are already starting to collaborate on open-source designs for objects and hardware.
