[pseudonymcoward]

Maybe I'm an idiot, but I was really struggling to understand how this worked from the website, which seems to have no photos or video of it actually operating.

I searched youtube and found a youtube short of it being used.

First you have to use another small machine to slice up a plastic bottle into a spool of roughly formed plastic spaghetti. Then you feed it through the nozzle on this machine to draw it into a properly formed filament.

Having to slice up every plastic bottle you want to run through it by hand seems like a cost to using it in any kind of bulk (I originally was trying to work out if it melted them down which would alleviate that).

[starkparker]

There's a small 3D-printing niche of PET #1 bottle cutting specifically for filament making. For whatever reason, they mostly seem to organize on Facebook.[1] A lot of these builds can be made out of scrap components.

The Recreator3D[2] somewhat automates the bottle cutting, feeding, and filament making. Older versions repurpose a specific 3D printer's hardware, but the MK6[3] uses largely off-the-shelf parts.

Igor Tylman sells kit and fully-assembled PETmachines that cut, feed, and pullstrude filament.[4]

1: http://PPU3D.com, which just redirects to https://www.facebook.com/groups/petpultrudersunited

2: http://recreator3d.com/

3: https://www.printables.com/model/352729-the-recreator-3d-mk6...

4: https://www.etsy.com/listing/1851116187/petmachine-fully-ass... with a pretty thorough demonstration at https://www.youtube.com/watch?v=WUcZyOWUzcY

[starkparker]

(worth noting that these pullstruders are all separate from the methods of shredding or grinding plastics into granules/pellets and using an extruder, i.e. https://www.youtube.com/watch?v=nQ0UyWKafAw, whose videos on the subject are good overviews of the process but tend to annoy me because they use pretty hobby-accessible tools for everything but the critical grinding part, for which he wheels out a sponsor's $10,000 commercial plastic grinder)