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3D printing fumes are NOT good for you. Malcolm Langille made an enclosure for his Type A 3d printer with exhaust system to extract the fumes outside of his house.I wonder how the temperature change and build surface cooling due to strong air movement affects the 3d print quality.
Source page with more details:
http://www.3dhacker.com/category/667/Type-A-Machines/listings/519/Enclosure-External-Exhaust-and-Fan.html
http://www.thingiverse.com/thing:197099
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