On a steep road on the outskirts of Oaxaca de Juárez, Mexico, a low buzz and plastic fumes emanate from a white house. A ribbed white paper tube snakes out of a window on the building, exhaling a light smoke which mixes with fumes from nearby open-air cooks and the sooty exhaust of rumbling, unmuffled bus engines. Inside, the tube is attached to a machine that’s gobbling plastic flakes—which can come from used drink bottles—through a funnel also made from a plastic drink bottle. At the other end of the machine, a spinning wheel draws out the fresh-melted polymer into a black filament just three millimeters wide and value hundreds of times what it was worth in in bottle form. Continue reading Building a New Economy on Soda Bottles and a 3D Printer →