Open source. Free. Built by anyone.

Turning Bottles Into Filament

One bottle. One idea. Our first project.
Officially partnered with Recreator3D since 2025

What It Is

Pultrusion, not extrusion

Standard filament is pushed through a nozzle. The Recreator3D pulls a heated strip of bottle through a die instead, spooling it into round, printable filament as it goes. That is the whole idea behind turning a recycling bin into a filament spool.

ExtrusionMelted plastic, pushed through a nozzle
PultrusionA heated strip, pulled through a die and spooled

1 PET
Why PET

Quick facts

Most recycled plastic

PET is one of the most widely recycled plastics on earth, easy to find, easy to reuse.

Genuinely strong

Recycled PET filament has tested competitively against commercial PETG and ABS.

Recycled at home

Turning a bottle into filament keeps it out of the waste stream entirely.

Built for beginners

The MK6 exists because the community asked for a simpler, cheaper way in.


Free and Open Source

Build It Yourself

Every file, part list, and instruction is free, no catch. Print the parts, source the hardware from your local hardware store, and follow the written guide start to finish. It is the same build we used ourselves, and it is meant to be shared with schools, makerspaces, and anyone curious enough to try. If you get stuck, the DIY guide walks through settings, troubleshooting, and the full parts list.

100% FreeNo license, no paywall
Fully Open SourceEvery file shared publicly
Guided BuildWritten, step by step DIY guide

The Machine We Recommend

Don't Want to Build It? Buy the MK6

Designed by Josh at JRT3D, built with KB3D. The MK6 Fun Size is smaller and faster than earlier builds, and made to be an easy first machine.

  • Compact, desktop printer sized footprint
  • Dual geared motor, faster and steadier pulling
  • Runs on PET number one bottles
  • About three times faster than the older MK5 build
  • Purpose built 12 volt parts, no printer to salvage needed
Recreator3D MK6 Fun Size pultrusion kit by JRT3D and KB3D
KB3D x Recreator3D MK6 Fun Size build kit box

MK6 Fun Size Kit, by KB3D

Skip the sourcing entirely. KB3D ships the official boxed parts kit, ready to build.

Boxed PartsHardware sorted and ready
Ships DirectStraight from KB3D
Official KitMade with Recreator3D
Shop KB3D

See It In Action

Watch bottles become filament

Real builds, real prints, real recycling. Follow along for the whole process.

Follow @eco.print3d
Instagram · @eco.print3d

Our Partnership

Partners with Recreator3D since 2025

Created by Joshua Taylor of JRT3D, whose whole mission is making it easy to turn waste into something new. We could not recommend it more.

Recreator3D created by Josh, JRT3D.com

Get Started

Everything you need is free

Files, guide, community, all waiting. Just add a bottle.