We have covered at least one DIY CNC hot wire cutter before, and commercial versions are manufactured by several companies including Hotwire Direct, Streamline Automation, and FoamLinx. This machine, built in 2006 by students under Dr. René Straßnick at the Technical University of Berlin, has two translational axes and a third, rotational axis consisting of a turntable to which the foam substrate is attached. Parts from an old dot-matrix printer were used to make the Cartesian robot. The project has four credited authors, one of whom (Jonas Pfeil) was later involved in the throwable panoramic ball camera project John Baichtal recently covered. [via nerdstink]
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this looks to be by far the best and most efficient
3d printing technique iv seen, almost makes all the others look like they been
wasting their time with the printing media.