3D Print Recycling

Note to ISU College of Design Students: Rather than throw out your prints please drop off unwanted prints at 1055 Communications during open hours. Please mark your prints with the type of filament used so it can be sorted appropriately for repurposing.

In 2013 President Barack Obama called 3D Printing a technology that has “the potential to revolutionize the way we make almost everything.” As this technology become increasingly more affordable and accessible, questions about how 3D printing will contribute to increased plastic pollution become more pressing. Plastic pollution is the accumulation of plastic products in the environment that adversely affects wildlife, their habitats and humans.

One of the common types of 3D printer filament is PLA which is not recycled by most curbside municipal recycling programs. Under the ASTM International Resin Identifier Codes, this plastic is classified as Type 7, or “Other”, which are not typically processed by municipal programs. As a result, failed 3D prints cannot be tossed into the recycling bin. A feature of the thermoplastics that are used in 3D printing is their ability to be melted down and re-extruded without a significant loss of material. 

At the CCL we are pursuing several filament reuse/recycling research initiatives. None of these processes are perfect and several require electricity input. Additional analysis and evaluation of these processes is required to determine replicability and environmental impacts.

Grinding + Respooling

This process requires a Filabot system (or similar) including an industrial grinder, a blender, an extruder, and a spooler which requires an approximately $6,000 investment in equipment and a 240-power supply. 

Additionally, this process does not allow for 100% recycled materials. Recommended ratios from Filabot are 30% recycled filament to 70% virgin filament. Resulting filament has thus far has yet to produce a successful 3D print. We are hopeful that with a new filtered nozzle and the new mixing technique that we can soon produce a successful recycled filament reel.

Grinding + Melting  

This process requires a standard toaster oven ($125). In which 100% ground filament is melted into sheets that are then post-processed into a new form. We are pursuing three strategies:

A. Directly CNCing the tile to create a new  surface

B. Heating and then vacuum forming the  plastic  tile over a CNC’d slump mold to  create a curved surface

C. Placing the warm tile over as CNC’d slump mold to create a curved surface

Future research will include creating custom dies to punch holes into the tiles as well as the development of custom metal forms for melting the ground filament in to specific geometries.