Recycling HDPE plastic containers into filament I've been researching the process of turning things like milk and detergent bottles into plastic that I could use in my printer. I think the idea of recycling plastic takes on a whole new appeal if people knew they could use the bottles to create free plastic objects. I think that the barrier now lies in the fact that currently you have to shred the plastic in order to recycle it into long lengths of filament. I have an idea that there could be a way to melt a bottle and push the melted plastic straight to the extruder nozzle during printing. I'm not sure if it could work, but I'd like to experiment with this idea more in the near future. https://reprap.org/forum/read.php?1,58224,58224#msg-58224 Thu, 13 Aug 2026 14:07:29 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,58224,127934#msg-127934 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,127934#msg-127934 jon.hulka General Mon, 09 Apr 2012 04:01:52 -0400 https://reprap.org/forum/read.php?1,58224,127818#msg-127818 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,127818#msg-127818 duno how well it would work once it got to the hotend, as I understand it the round filiment expands as it heats up blocking the hole in the ptfe and stopping backflow.
another problem you're going to have with HDPE is it shrinks a lot as it cools. so it's not easy to print with.]]> se5a General Sun, 08 Apr 2012 06:36:56 -0400 https://reprap.org/forum/read.php?1,58224,127790#msg-127790 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,127790#msg-127790 jon.hulka General Sun, 08 Apr 2012 00:55:36 -0400 https://reprap.org/forum/read.php?1,58224,110929#msg-110929 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,110929#msg-110929
Check the Site out here.]]> Tyler McNaney General Thu, 22 Dec 2011 17:18:11 -0500 https://reprap.org/forum/read.php?1,58224,67013#msg-67013 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,67013#msg-67013 murrayd General Thu, 25 Nov 2010 18:59:40 -0500 https://reprap.org/forum/read.php?1,58224,66996#msg-66996 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,66996#msg-66996 AgeingHippy General Thu, 25 Nov 2010 06:13:23 -0500 https://reprap.org/forum/read.php?1,58224,66985#msg-66985 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,66985#msg-66985 hintss General Thu, 25 Nov 2010 00:56:47 -0500 https://reprap.org/forum/read.php?1,58224,66927#msg-66927 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,66927#msg-66927
You are right, there really isn't much plastic in a milk jug but you can get pretty well all you want by buying it from your local recycler for what they would get paid or being the local recycler. Thats kind of a lifestyle choice. I happen to live next door to the most active local recycling advocate so its not an issue with me.

Additionally, the ability to melt down your own plastic and extrude it will make failed print jobs a lot easier to deal with.

On the side , I would expect that the presence of such a system would put more pressure on the idea of having the print head stationary like in the makerbot, than have it move around like in darwin and mendel. Personally I see strengths in both configurations but I lean towards the stationary printhead idea. Neither are evil. :-)

I'm very interested in the recycling plastic idea. If I could get enough printable plastic cheaply, I could print larger and more things which leads to greater usefulness.]]> foxpup General Wed, 24 Nov 2010 11:12:19 -0500 https://reprap.org/forum/read.php?1,58224,58332#msg-58332 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,58332#msg-58332 Grains->Extruder.

Also, I think you need a few hundred plastic bottles to have a few pound of thermoplastic. A Personal Recycler may be a blind alley or frustrating process compared to doing stuff through a local filament supply place that can buy a ton of shredded recycled plastic at a time. (I'm not sure.)]]> SebastienBailard General Tue, 07 Sep 2010 13:44:02 -0400 https://reprap.org/forum/read.php?1,58224,58315#msg-58315 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,58315#msg-58315
]]> jkelso General Tue, 07 Sep 2010 11:17:42 -0400 https://reprap.org/forum/read.php?1,58224,58235#msg-58235 Re: Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,58235#msg-58235
Maybe. (:D

(It's not in the wiki, but someone may have done it already on a personal blog.)]]> SebastienBailard General Tue, 07 Sep 2010 00:01:15 -0400 https://reprap.org/forum/read.php?1,58224,58224#msg-58224 Recycling HDPE plastic containers into filament https://reprap.org/forum/read.php?1,58224,58224#msg-58224 jkelso General Mon, 06 Sep 2010 22:06:14 -0400