Use PET bottles for your 3D printer

We all agree that the recycling of plastics entails a considerable logistical effort. While working at a makerspace in Rwanda, Swaleh and Reiten Cheng discovered that many locals were unable to use 3D printers due to the high cost of importing filament into the country. They also noted the lack of infrastructure for recycling plastic bottles in Rwanda. And they created”.Polyformer“a machine, that recycles PET bottles (90% of plastic water bottles are PET) into filaments for 3D printers. into filaments for 3D printers.

The machine is not for sale, you can build it yourself with a 3D printer and the instruction manual.

On their website you will find the links to download the parts and the rest of the components are easy to obtain. Its modular architecture allows the machine to be modified as required and its vertical L-shape minimises the amount of space it takes up.

This idea was awarded the prestigious international James Dyson Award for design.

By converting used plastic bottles into filament for 3D printers, Polyformer helps reduce the amount of waste going to landfill and provides a cheap and plentiful material for engineers and designers, especially in developing countries. His idea will provide new opportunities for other inventors to prototype their ideas using 3D printing.

Sir James Dyson, founder and chief engineer of Dyson.

Currently, Swaleh and Reiten are building new Polyformers to deploy in their partner makerspaces in Rwanda and are designing new inventions within the Polyformer project, such as the Polyjoiner, the Polydryer and the Polyspooler.

  • Polyjoiner: A standard 500 ml plastic bottle can only produce 3 m of filament, which is not enough for most print jobs. Swaleh and Reiten have therefore developed the Polyjoiner, a mechanism that can automatically join several strands of printer filament into one long piece.
  • Polydryer: PET is hygroscopic, which means that a plastic water bottle can absorb some of the water it is filled with. The presence of water in the filament negatively affects the print quality. Swaleh and Reiten are therefore developing Polydryer, a low-cost machine that evaporates moisture from the filament of 3D printers.
  • Polyspooler: Long 3D printer filaments need to be wound onto a spool. This ensures that the filament does not tangle while the printer is running. The Polyformer team is developing the Polyspooler, a simple machine that automatically spools recycled filament, making it more practical to use.


In summary, the“Polyformer” is a PET bottle recycling machine that offers an efficient, versatile, low-cost and environmentally friendly solution for plastic recycling. And it is leading the way towards a more sustainable future in plastic waste management. We think this is a great idea. What about you?

Disclaimer: Images by James Chou. Vía @Diegoquirozl and Ecoinventos

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