For decades the lowly office printer inspired one thing and one thing only; the search for a new toner cartridge. Then in 1983 (the year of the camcorder and the compact disc, incidentally), a guy named Chuck Hull successfully tested his prototype of a sleek little something he called the stereolithographic apparatus. Yes, the marketing folks had their work cut out for them with that one, but they would have plenty of time; Hull’s invention would not hit the market for nine more years. Much of the magic of those early machines was in the “ink.” The laser-solidifying photopolymer could be goopily extruded into precisely shaped, computer-assisted layers which, when properly stacked, became 3D objects. Smallish ones, at first.
When the early-gen 3D printer was finally offered to the consumer, in 1992, it did not immediately set the world on fire. As is always the case with a bold new innovation, though, there were imaginative individuals who saw in the idea of “printed objects” an immense opportunity.
Clearly this new tech would one day take manufacturing to scalable new frontiers, but who would’ve guessed it would revolutionize internal medicine? Hull’s novelty gadget, it turned out, was not just a printer; it was a producer, capable of rendering computerized 2D designs into functional real world objects. And you would never have to remove and shake the toner cartridge.
Today's 3D Printing
Today, 3D Printing (3DP) is being used to print everything from airplanes to blood vessels to buildings. Construction in particular stands to benefit from the amazing efficiencies inherent in 3DP. The European Space Agency is even exploring the off-world possibilities of 3DP, developing a model for printed architecture on the moon that uses lunar dust and a binding agent.
The rapid-set nature of the concrete, combined with its elastic properties, means the “printed” structures can have curvaceous, non-linear shapes, unlike the more cubist fare dictated by the traditional wooden forms into which concrete has been poured for 160 years.
Here on Earth, developments are just as startling. Dr. Berok Khoshnevis of the University of Southern California, a pioneer of 3DP in construction, has developed a system he calls the Contour Crafting System. The Contour Crafting System uses a specially devised “printable” quick-set concrete that cures quickly into load-bearing strength, dispensing layers of exactingly shaped concrete that also render the precise design spaces for electrical and plumbing within the printed walls. Though his experimental large scale printing experiments were not initially concerned with buildings, Dr. Khoshnevis was inspired by the devastating earthquakes in his home country of Iran to begin focusing his experimental technology on the need for rapid rebuilding of homes in a post-disaster setting.
What does this mean for construction?
Apart from the speed of construction (a critical factor in a housing emergency), there are other advantages to printing a building. Because the printable concrete sets so quickly, there is no need to pour it into the sort of framing system normally needed in concrete construction, and therefore, there’s less waste material in the building process––not to mention the smaller carbon footprint. Add to that the fact that the rapid-set nature of the concrete, combined with its elastic properties, means the “printed” structures can have curvaceous, non-linear shapes, unlike the more cubist fare dictated by the traditional wooden forms into which concrete has been poured for 160 years. In this way, printable construction is also a gift to architects and designers. Recent efforts to standardize a jobsite-ready machine include the CyBe ProTo 3DP Concrete 3D Printer, which offers a smooth, more aesthetically pleasing surface texture than the scalloped look that so far typifies the necessarily layered 3D construction attempts.
The very nature of 3DP should lend itself nicely to the showpiece project of DUS architects, a design firm in the Netherlands which is attempting to 3D print a canal house in Amsterdam. DUS is hoping to demonstrate the use of eco-friendly and renewable materials in the project. And the other-than-linear 3DP possibilities will allow the builders to match the off-kilter leaning for which Amsterdam’s architecture is famous. With a little paint and some wooden shoes by the entry, DUS’ 3DP canal house should fit right in.
*watch this space for an exclusive interview with Dr. Khoshnevis