Jude Pullen was toying around with a home vacuum former called the Mayku Formbox. The machine allows you to create vacuum formed shapes at home fairly easily. Pullen had the idea that it would be great if he could use upcycled material instead of buying plastic each time.
As it turns out, only a few simple modifications were necessary to make this work with sheets cut directly from milk jugs. Though the modifications were for the Formbox specifically, all he’s doing is blocking the breeze to attain a slightly higher temperature – something you could do to any machine.