Plastic Smithing: How To Make your own HDPE Plastic Anything (DIY plastic lumber)


Step 2: Add oil, and stew.

Picture of Add oil, and stew.
It doesn't really matter what polyethylene you use, you can melt HDPE plastic bottles in too, if you want.

That is, Resin Identification Code #2 and #4 are both good.

Polyethylene Terephthalate, that is PETE/PET or #1, may also work.

EDIT: Thanks to reader concern, I will state what may not be obvious from the pictures: there are no fumes. There's no smoke, no fans, no inhalation hazard. If there's smoke or fumes, you're doing something wrong and you're burning the plastic. That's why you use oil for temperature regulation.

The plastic bags do this alive-shrinky thing that looks really neat, so I took a video!

Viaticus3 years ago
If bags melt at 250, why not melt them in an oven instead of in oil?
Endif4 years ago
So one could use any oil? What about used motor oil? And does the plastic soak up/bond with any of the oil, or does it simply remain in the pot for re-use? In a scenario where this technique would be most valuable (post-modern-civilization), food-grade oils will be far too valuable to waste on something like this. I guess one could use oil that has gone rancid...
PET won't work. It will melt/shrink a lot/release dangerous fumes at that temperature.
mum5 years ago
So there's no stink or fumes from doing this?I have been making plastic bottle beads n I have just done 1 on Shrinky plastic medallions I am now gonna have a look at this...... First have 2 find old pan from shed!