A self-replicating 3D printer that spawns new, improved versions of itself is in development at the University of Bath in the UK.

The “self replicating rapid prototyper” or RepRap could vastly reduce the cost of 3D printers, paving the way for a future where broken objects and spare parts are simply “re-printed” at home. New and unique objects could also be created.

3D printing – also known as “rapid prototyping” – transforms a blueprint on a computer into a real object by building up a succession of layers. The material is bonded by either fusing it with a laser or by using alternating layers of glue. When it first emerged in the mid-1990s, futurists predicted that there would be a 3D printer in every home.

But they currently cost $25,000 (£13,000) and so have not caught on as a household item, says Terry Wohlers, an analyst at Wohlers Associates, a rapid prototyping consulting firm in Fort Collins, Colorado, US. Instead, they are used by industry to develop parts for devices such as aircraft engines, spaceships and hearing aids.

Now Adrian Bowyer hopes to change that by making the first 3D printer capable of fabricating copies of itself, as well as a wealth of everyday objects. He reasons that prices would plummet to around $500 if every machine was capable of building hundreds more at no cost beyond that of the raw materials.

Better still, the machines could evolve to be more efficient and develop new capabilities, says Bowyer. Once he has the software to guide the self-replicating process, he plans to make it freely available online, allowing users to contribute improvements, just like the open-source Linux computer operating system, he says.

Bowyer dreamt up the idea of the RepRap in February 2004. But now he has he figured out how to print conducting materials in three dimensions without using a laser, a key step if the machine is ever to make copies of itself.

“We are very constrained in our access to materials,” he explains. They must be sturdy enough to make up the body of the machine and yet simple enough to be fabricated entirely by the machine. “We have to avoid any design needing lasers and high precision measuring systems,” he explains.

More here.