A maker turned discarded drink bottles into printer filament

It took 17 plastic bottles to make one kilogram of 3D printer filament. The YouTube channel PETCraft counted them in an October 10 video, and Hackaday’s Maya Posch tallied the haul: thirteen 5 liter bottles, a 10 liter, two 8 liter and a single 1.5 liter bottle.

Play the video on YouTube

The bottles started out as trash. Hackaday says the channel’s owner clearly lives in a country without a bottle deposit, where PET bottles are strewn about as trash, multi-liter water bottles included, which makes the raw material free for anyone willing to collect it.

Every machine in the process is homemade. Hackaday writes that the bottles are heat-smoothed to make them easier to cut into thin strips, cut on a DIY cutter built from mostly salvaged parts, then pulled through the heated nozzle of a DIY extruder and wound onto spools. The video’s own description says the smoothing happens “over a gas stove” and the extruder turns each strip into 1.75mm filament.

Whether it’s worth it is still open. Hackaday asks whether cleaning, cutting and spooling dozens of bottles “is worth saving perhaps 10-20 bucks on a commercial spool of 1 kg PETG filament.” Its commenters argue over whether bottle plastic behaves like the filament you buy. Nobody has printed with this spool yet: PETCraft says the next video will test it on a budget DIY 3D printer built with an Arduino Uno.

If you have a printer and a pile of bottles, watch part two before you build a cutter. The kilogram is real. How well it prints is the part nobody knows yet, and that’s what decides whether your recycling bin is a supply closet.

Seventeen trash bottles is a lot of work for one spool of filament, and I’d still rather see them on a printer than in a ditch.