phones that also act as base stations, routing calls from peer to peer. This free communication would have a phenomenal impact on developing countries. Another possibility is DIY medicine; as drug patents don’t apply to personal production, expensive patented medicines could be saving lives worldwide if the machines could be made to produce them.

You would be forgiven for thinking that a project like this would be incredibly high-tech and well-funded, but there is a strong amateur element, composed of enthusiastic makers. The RepRap plans and software are freely available under a GNU license, and participation in the project is open to anyone with the skills and motivation. The benefit of a project that aims to create a simple machine is that the barriers to entry are very low; you could build your own machine and start to refine and improve components, or help to develop and improve the software. There is even demand for help with the project documentation.

Zach Smith is a web developer by trade who took a few electronic engineering courses in college, and is building his own machine. “All I know about the circuits, I found out by asking questions and looking online,” he says.

Forrest Higgs, whose background is in aerospace engineering and architecture, has one too, and he’s trying to refine the concept by deviating from the main plans. He proclaims to be on the “bleeding edge,” and any improvements he makes will be fed back into the project.

Some parts to create the machines are currently bought, rather than produced by a parent machine. “We buy nuts and bolts, as it’s cheaper and easier. It would be nice to have a pure machine, but I would imagine that it would be some time before these readily available parts are produced by the machine itself, even when they are possible to be made,” says Bowyer. Some of the home-builds even use Lego, Meccano, or wood to build the chassis.

According to Bowyer, within two years the RepRap machines could be producing all their constituent

An early experimental polymer extruder, with assorted components and materials.

parts, even electrical circuits. “There are two alloys, Wood’s metal and Field’s metal, which have lower melting points than that of the plastic used in the machine’s construction. We would have a small chamber that heats this alloy, and we can then extrude this from the same nozzle we use to extrude the plastic. The big advantage is that you can then put a layer of plastic on, and another layer of alloy — you have 3D circuits. You can then hide these circuits in the actual structure of the machine.”

The controlling computer will probably be pre-produced for the foreseeable future. The software is currently written in Java because of its platform

“Making complicated things is not a large step, certainly not as large as the step from making nothing to making simple things.”

independence, but the team is closely watching MIT’s $100 computer project ( laptop.org); it would provide a perfect controller, is affordable, and could use the same 12-volt power source as the RepRap machine.

RepRap has the potential to do something really revolutionary, to bring about a manufacturing singularity with a very real impact on people’s lives. The idea that these machines can reproduce and evolve is fascinating. The hackers who make up the RepRap project will constantly improve the design, making it simpler to make and more capable. What better outlet is there for your maker tendencies?

Matt Sparkes lives at mattsparkes.org, and also in London.

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