Can you 3D print with trash plastic?

Turns out, yes, you can! After building the Precious Plastic shredder and several extruders, I decided that making good filament for 3D printing was too hard to be practical, and started designing an extruder that can print large objects directly from recycled plastic flakes.

It works!

There’s still a lot of room for improvement, but I am now able to print strong, light, large parts directly from recycled plastic flakes. This wind turbine was printed in about 45 minutes, using recycled #5 polypropylene flakes, from one-time use centrifuge tubes sourced from a local company.