This machine recycles plastic water bottles into 3D printing filament (and it is open supply)


This is a prototype of the Polyformer.

Picture: Reiten Cheng

Plastics, ecologically talking, have gotten a fairly unhealthy repute over time, usually fairly deservedly so.

Nonprofit ocean conservation group Oceana reviews that two rubbish vehicles price of plastic enters the world oceans each minute. That is 33 billion kilos of plastic coming into oceans yearly. Mapping service Arcgis has charting knowledge that exhibits there are 5 main patches of plastic-covered ocean protecting 20 million sq. kilometers (7.72 million sq. miles). That is sufficient plastic to blanket Alaska, Texas, California, Montana, and New Mexico (The USA’ 5 largest states by space).

The US Environmental Safety Company reviews that the US generated 35.7 million tons (roughly the load of 17.8 million Tesla Mannequin 3 autos) price of plastic. General, solely 8.7% of the plastic produced is recycled, however that price differs based mostly on the kind of plastic as a result of various kinds of plastics have very completely different chemical properties.

PLA, or polylactic acid, is the commonest kind of plastic utilized in 3D printing. It is a very easy-to-use materials, it adheres to the print mattress effectively, and is fairly strong for a lot of makes use of. It deteriorates within the solar and could be brittle, however the overwhelming majority of things I’ve made have been printed with PLA as a result of it really works effectively in extrusion 3D printers.

PLA has some pluses ecologically, as effectively. Slightly than being produced from fossil fuels, it is produced from renewable assets like corn, cassava, sugarcane or sugar beet pulp. PLA can also be biodegradable, though there are some particular footnotes to that declare. It doesn’t compost effectively. About half of the fabric decays over time, however the remaining can stay for lots of and even 1000’s of years. You do not need to dump PLA in landfills for a similar purpose. butt PLA does incinerate fairly properlyleaving no residue or poisonous fumes.

In the case of recycling, PET (or polyethylene terephthalate), is one thing of a winner. In response to the EPA, practically 30% of all PET has been recycled. That is massively vital as a result of PET is the fabric used to make plastic water bottles and jars. In response to the College of Southern Indiana, Individuals use 2.5 million plastic bottles each hourmost of that are thrown away after use.

A modified variant of PET, generally known as PETG (polyethylene terephthalate glycol-modified), can also be fairly fashionable in 3D printing. PETG replaces the ethylene glycol in PET with cyclohexanedimethanol, which provides six further carbon atoms. This makes the molecular construction much less tight, and that enables the plastic to soften at a decrease temperature.

PETG will soften at about 230 levels C. In contrast, PET (the water bottle plastic) will soften, however at temperatures nearer to 280 levels C. That is close to the highest finish of the temperature vary for many hobby-level extruders on 3D printers.

The truth that PET can technically be 3D printed opens up a easy query: How can we flip water bottle plastic into 3D printable filament?

Reiten Cheng, an industrial designer who simply graduated this spring from Pasadena’s ArtCenter Faculty of Design, appears to have a solution. And it is open supply. He calls it the Polyformer.


Polyformer heated extrusion mechanism

Picture: Reiten Cheng

The thought for the Polyformer is easy. Use a pair of scissors to chop the underside off of a water bottle. Insert the bottle within the Polyformer. The machine slices the bottle into strips. An extruder heats the strips and pushes out plastic filament. From used bottle to ready-to-use filament, it is an thought with potential.


Picture: Reiten Cheng

Whereas filament does are available in bigger and smaller quantities, most filament is offered on 1 kilogram spools. Once I spoke to Cheng on his Polyformer Discord channelhe advised me that roughly 33 bottles would create a kilogram spool of filament.


Picture: Reiten Cheng

I see this as an incredible group or makerspace venture. A college or makerspace may accumulate the bottles and switch them into filament spools.


3D printed components and extra parts that make up the Polyformer

Picture: Reiten Cheng

As I discussed above, PET is a little bit of a problem to 3D print, particularly with how stringy it will get and the way troublesome it’s to dial within the temperature settings. However as soon as that found out, a faculty or makerspace may have a just about infinite (and free) provide of this very strong 3D printing materials.


I used to be significantly interested in how the bottles are minimize. Discord person @Alextrical advised me that, “It is the bearings that minimize the bottle, the sides slide over one another and shear the plastic much like scissors.” So this could be secure in a group setting, and there aren’t any points concerned in sharpening or changing blades.

It must be famous that Cheng is not the primary to construct a PET plastic bottle to filament recycling machine. He cites as inspiration Joshua Taylor at, which has plans and components lists for the same machine. Taylor’s method is to transform a Creality Ender 3 3D printer right into a “Plastic Bottle Pultrusion Unit”.

It is an fascinating method – upcycling a 3D printer to make a tool that recycles plastic bottles for use as filament for a 3D printer.

So what about you? Do you suppose you may construct a tool like this? Do you wish to do your half in recycling plastic bottles by turning them into 3D printing filament? Tell us within the feedback beneath.

You may observe my day-to-day venture updates on social media. Remember to observe me on Twitter at @DavidGewirtzon Fb at Instagram at on YouTube at

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