How to Make 3D Printer Filament from Plastic Bottles – 6 Steps
Reading Time: 9 minutes Whether you’re a seasoned user or a complete newbie, making 3D printer filaments from plastic bottles can be exciting. The process is not very complicated, especially if you love DIY projects. No need to worry if you don’t. I wrote this guide to walk you through the whole process.
To make 3D printer filament from plastic bottles, you need to assemble a PET bottle-to-filament-making machine and prepare your plastic bottles. After that, cut the bottle into long strips of uniform width and feed them into the hotend of your filament-making machine to get 3D printer filament.
This is just an overview of the process. I am going to go into more detail in the article, so stick around to find out more.
How to Make 3D Printer Filament from Plastic Bottles
Here is the step-by-step process of turning plastic bottles into 3D printer filament:
- Gather the materials you will need for the project
- Assemble your PET bottle-to-3D printer filament-making machine
- Prepare your plastic bottles
- Cut your plastic bottles into long strips of uniform width
- Prepare your filament-making machine
- Feed the plastic strips into your hotend and pull out the 3D printer filament
1. Gather the Materials you will Need for the Project
The first thing you should do to make 3D printer filament from plastic bottles is to gather the materials and tools needed for the project. Collect the PET bottles that you would like to convert into useful filament.
Empty soda, juice, or water bottles are good examples, so if you have some lying around, that will do. Next, you’ll need to gather the tools that you will need for the project, including:
- Air compressor – This will be used to inflate the bottle to smoothen it
- Hot air gun – After inflating the bottle, the hot air gun will heat the bottle to smoothen it further
- Scissors – They will be used to remove the bottom part of the bottle, which will not be needed. It will also cut a strip from the bottle, which will be fed into the bottle cutter.
- Razor Knife – It will be used to make a small incision on the bottle before you can cut it with scissors.
- Drill – You will use it to rotate your bottle as you heat it with a hot air gun.
- Pliers – It will help you to pull the plastic strips as the bottle cutter strips your bottle. You will also use it to hold the filament as it comes out of the hotend of your PET machine.
2. Assemble the PET Bottle-to-3D Printer Filament-Making Machine
To transform 3D Printer filament into plastic bottles, you will need a PET bottle-to-3D printer filament-making machine. Many experienced users normally create one for themselves using parts from a normal 3D printer.
However, I understand it can be challenging if you’re a newbie. If that is the case, purchasing and assembling a kit would be the best way forward. Two kits come to mind immediately:
Tylman Design PET Machine
The first kit that I would recommend you to get is the Tylman Design PET Machine that is available on Etsy.
One user said this was a fantastic kit to jumpstart the building process on the PET machine. He added that building the machine was fun, and he learned so much from it. He recommended it to anyone who wanted to make filaments at home from plastic bottles.
Another user said that they were amazed by this PET machine after they bought it. They wanted to buy a ready-made kit to make their own filament and were not disappointed since the kit they received was complete, clear, and easy to follow. The end result was a clean and great job.
In this video, Tylman Design perfectly explains how to assemble this machine to make your own filament at home.
The Recreator 3D MK3Pro
The MK3Pro Kit is another simple yet great design that can help you convert your PET1 plastic bottles into 3D printer filament. According to the makers, this machine can strip, reform, color, and spool all in one cycle.
A user said that this was a great device, and he really enjoyed making filament from PET bottles with it. He added that it printed very well once it was up and running.
After downloading all the files from Printables, you can check out the video below on assembling this unit.
3. Prepare your Plastic Bottles
Once your PET machine is fully assembled, prep your PET bottles to make the 3D printer filament. The process of prepping the bottle involves the following:
- Remove the carrier, lid, and labels from the bottle so that it remains bare. To get rid of the adhesive that was used to stick the label, wet a paper towel with alcohol and rub it until there is no residue.
- Wash the inside and outside thoroughly to ensure that you get good-quality filament. You can do this using water, soap, and a clean cloth for scrubbing. After that, dry the bottle using paper towels or a clean cloth.
- You’ll also need to smoothen out the bottle. Begin by pressurizing it using an air compressor or bike pump. Be careful not to over-pressurize it since it can burst. Use a drill to slowly turn the bottle while heating it with a hot air gun.
You can use this Comoware 20V Cordless Drill available on Amazon.
- 【20 Voltage & 2 Variable Speeds】 Higher voltage means more torque-spinning strength to overcome resistance. This 2 variable-speed ( 0-350 & 0-1300 RPM ) cordless drill with an adjustable clutch gives you the versatility for drilling different materials and using a variety of bits. The low speed is for driving screws, the high speed is for drilling holes.
Prices pulled from the Amazon Product Advertising API on:
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.
This will remove all the ripples and grooves to make the surface smooth. You can do as shown in the video below.
The MAXXHEAT 1800W Hot Air Gun you can find on Amazon would be perfect for this application.
- -Confident With Quality: 24 Months Warranty and Life-Time Customer Service
Prices pulled from the Amazon Product Advertising API on:
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.
4. Cut Your Bottles into Long Strips of Uniform Width
Next, you need to create a strip of plastic bottle of uniform width to be fed into the machine to make the filament. Here is how you can do it:
- Cut off the bottom part of the bottle from where the width starts to change.
- Make a small incision using a razor knife and then cut all around using scissors to remove the bottom part of the bottle. Cut another small strip that will be inserted into the bottle cutter/stripper.
Use this Craftsman Utility Knife and Westcott Titanium Scissors found on Amazon.
- Twin blade design allows the user to alternate between two blades without carrying more than one knife
Prices pulled from the Amazon Product Advertising API on:
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.
- Place the bottle on your cutter and slice it into a long strip of uniform width. The MK3Pro Kit comes with a bottle cutter. However, the Tylman PET machine doesn’t. You can make your own bottler cutter, as mr3dp shows in the video below.
You should consider the width of the strip when producing 3D printer filament from plastic water bottles. It is important to choose the right width to produce good quality filament. The width of the strip usually depends on the thickness of the bottle.
If the width is too narrow, the filament will not be a complete tube, and your filament will not process through a 3D printer. On the other hand, if your ribbon is too wide, you cannot pull it through the hot nozzle.
One user said he chose a width of 6mm for 0.5mm thick bottles and 8mm for 0.3mm thick bottles.
Another user posted a chart for determining the width of strip to cut depending on the thickness of the bottle.
| Thickness of Bottle | Width of Strip |
| 0.2mm | 10mm |
| 0.25mm | 9mm |
| 0.30mm | 8mm |
| 0.35mm | 7mm |
| 0.40mm | 6mm |
| 0.45mm | 5mm |
5. Prepare Your PET Machine
Before loading your plastic strip into the extruder, prepare the filament-making machine. This involves adjusting settings for optimal filament production, such as hotend temperature and feeding speed. Heat the nozzle to prepare for feeding the plastic strips.
One user said the trick to making 3D printer filament from plastic bottles is to use a much lower temperature so the plastic only gets soft instead of molten. On his setup, he ran the PET strips at 220°C while the printing temperature of the filament was 260°C.
6. Feed the Plastic Strips into Your Hotend to Form 3D Printer Filament
After prepping your PET machine, feed the plastic strip into your hot end. Push it into the extruder and use pliers to hold the filament as it gets out of the nozzle. Pull it firmly until you have enough length to secure it to your geared puller, which also acts as the spool in some machines.
Once you have a suitable length, secure it to the geared puller of your PET machine. Start the geared puller and let it pull at a controlled rate if firmly in place.
This turns long strips from plastic bottles into 3D printer filaments that you can use.
Mr3dp has one of the best video tutorial series on how to make 3D printer filaments from plastic bottles.
