Inexpensive SLA printer design including VAT design

Hi,
I am starting to design and build a DLP printer. I am trying to make it the cheapest (yet effective) DLP printer (using your own preferred projector). I have drawn up some designs and have some concepts. This is all a little besides the particular point of this thread, that is providing all of you my new found solution for a flex vat that is super cheap and super easy, AND provides a relatively large build volume! Anyways let me jump into it.

So The other day I was back on trying to thin