FROM msnbc article, updated 4:47 p.m. CT, Wed., Nov . 4, 2009; by Jeremy Hsu of space.com

MY SUMMARY

NASA has developed a technology called Electron Beam Freeform Fabrication (EFB3), which could enable on-site manufacturing allowing creation of spare parts, like a bolt, screw, even shovels. The method uses an electron beam to melt metals and build objects layer by layer, then adjust the speed that you feed the wires, and that would change the shape of the object or even it's very chemistry if two or more material types are available. All it requires is three crucial things: power for its electron beam, a vacuum environment, and a source of metals (presumably wires are the ideal shape fo the metals). Somebody feeds metal wires continually into the tip of an electron beam. The beam melts the wires and applies them carefully on top of a rotating plate to build an object up slowly, layer by layer. Broken parts need not remain useless - they could simple be recycled, namely by placing the part back into the feedstock, or can we mine new material. The idea is to bring along the material needed to make the part or tool, but, but not the tool itself. NASA researchers managed to build a prototype roughly the size of a suitcase, to be tested later in orbit.

EBF3 already promises to cut manufacturing costs for the aerospace industry, and could pioneer development of new materials. They foresee cost savings of up to $1,000 per pound of manufactured parts, compared to the usual forging and machining methods that require a 6,000-pound block of titanium to produce a 300-pound part. Furthermore, one could embed fiber optic cables inside a solid piece of metal, either for use in communication or for monitoring stresses within the manufactured part.

Major aerospace manufacturers have already begun running thousands of strength tests with the EBF3 device to see whether it can produce certified parts for engines and airframes, researchers said. Furthermore, it can even allow onsite manufacturing of small parts in orbit - manufacturing tools with materials already available on the Moon, Mars, and other places. Although the weight of the raw materials will equal the weight of the completed parts, it will make storage of the material quicker and cheaper, reducing mission costs.

Boy, that post is pretty difficult to read, you know?

It's very interesting that this technology is almost ready to be tested in space. I think the key to exploring the solar system (and beyond) is to do less with more. Rather than build heavy lift rockets or space elevators, I think it is much more likely that we will develop ways to make use of resources that are already in space, rather than lug them out of earth's gravity well. I can imagine a much improved version of this device being used to create exploratory robots or habitats or whatever is desired on the surface of the moon or mars. (And of course this sort of thing is quite useful on earth as well.)

Yes, exactly. It's the first small step to breaking our Earth-dependency.

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"The Mayan symbol for "book" looks a lot like a triple hamburger, but I've never seen them claiming it as proof the Mayans had Big Macs." - KaiYeves
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