Couple questions about vacuum forming

[bacteria]

I found a good solution for the screw posts a few days ago, and I will use in my current/future portables to screw the two perspex sections together - finally got a supplier for small nuts and bolts - "screw sets for fan fix" from Maplin - computer DIY accessories - basically small nuts (5mm), screws (which can be cut down as needed) and washers - ideal! Far better than relying on perspex alone as screwposts. Holes can be made in the perspex just bigger than the screw itself, and the washers will sandwich the perspex, reducing damage and ensuring a fast hold.