How to Recycle HDPE (milk Bottles and Caps) Into Usable Sheet Material





Introduction: How to Recycle HDPE (milk Bottles and Caps) Into Usable Sheet Material

I discovered an easy way to recycle HDPE into small sheets of tough, rigid material, using a flat sandwich toaster.

Here's a video of the process:

And here's another showing various ways of working the plastic material:

Source material can be found in the form of plastic milk bottles (also some bottles from household cleaning supplies, toiletries).  Some bottle caps are also HDPE.

Briefly, the process comprises:

Cut the bottles and caps up into small pieces - about 1cm square or smaller is good.

Preheat the sandwich toaster (mine goes to 180 Celsius, which is perfect, as this will melt HDPE to a sticky, toffee-like consistency without burning or producing any noxious fumes).
Place a reusable nonstick baking sheet on the bottom plate of the toaster, then add a heap of HDPE fragments.  Place another nonstick sheet on top and press the toaster closed.

After a few minutes, the plastic will melt together into a rough sheet - take this out (don't attempt anything without the gloves), peel off the top layer of nonstick and fold in the edges of the melted plastic, then replace the nonstick sheet and put it all back in the toaster.

Repeat until you have a solid blob of melted plastic between the two nonstick sheets - then clamp this between two flat boards to cool.

Once cooled, the plastic will be very tough and rigid - and can be cut and shaped with hand tools, or machined.

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Since this is so slippery, would it be reasonable to make bearings from it? I mean, for light loads of course.

I'm fairly certain that's how they make plastic bushings.

Would it be possible to use this product as a roof slate/tiled. Obviously if using industrial machinery?

Hi does any one have or know of a list of all hdpe sources i.e which bottles are hdpe or not as my first attempt failed due to non hdpe in the mix

Hi, can this plastic be milling or machined ?

I don't have a flat sandwich toaster. What about using an electric stove and a flat pan and stirring the shredded plastic over the baking sheet?

You'll destroy the pan but if you don't mind.. it will work

Very nice. My suggestion would be to use a crosscut paper shredder if available to help with the cutting of the milk cartons. It would make shredding much easier.

Paper shredders aren't generally man enough for the job (I tried).

I did actually build a shredding device made from a Spong mincer, powered by an electric drill and gearbox - and this was reasonably successful - I had a plan to try to weld sheets of recycled HDPE together to skin a canoe (details here:, but it was too hard to get a consistent quality on the joints

Could you cut to strips then weave them together into sheets, then paint some kind of plastic sealant over them; would that be stronger than welding flat sheets?