Drink the water, feed the bottle to the 3D printer!
Back In 2013, Dennon Oosterman and his former classmates Alex Kay and David Joyce grew tired of churning through expensive filament for their 3D printer. So they built a machine that could recycle it back into usable form. The $700 ProtoCycler now released grinds scrap plastic — such as empty bottles and rejected 3D-printed models — into digestible pieces, melts it down, extrudes it, and winds it onto a spool. To ensure consistency, a computer-controlled diameter-feedback system uses two cameras to accurately measure the width of the filament.