An extruder is composed of four main elements, which include a motor that rotates and a worm screw inside a sheath heated by resistors.
Benchtop Extrusion Machine Turn Your Plastic Waste Into Products
Precious Plastic Monson by Melissa Miller — Kickstarter
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Applied Sciences, Free Full-Text
Machine Recycles Plastic Bottles into 3D Printer Filament–And the Design was Released, Instead of Patented
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Extrude beams from plastic waste #preciousplastic
Recycling Academy, online training for recyclers