Sorry to keep coming back on this one - I've had a look around and I'm getting a bit confused about the high density foam - I keep finding stuff on rolls and that can't be right!
Is it the same stuff they use for insulation? I'm assuming it's going to be a lot more dense and a lot tougher than that.
I found this stuff, but it seems a little on the expensive side for 30cm x 30cm;
http://www.easycomposites.co.uk/products/pattern-making/high-density-polyurethane-foam-block.aspx
I also found these guys;
http://www.tridentfoams.co.uk/tricast.html
Just curious if I'm on the right track, at the moment I can't see how I'd get the correct thicknesses from something like this, whereas with MDF I can get thinner sizes, or layer up.
I'm keen to use the foam if that's the most suitable material, I'm just wary of spending on the wrong thing!
Thanks again.
The name "Foam" is tossed around a lot, but there are different types of foam. My beer has foam, but I can't build anything with it. They are classified by chemical base, rigidity, and density.
Flexible Foam will come in sheets or rolls, and can be Polyurethane, Polyethylene, EVA (Ethylene Vinyl Acetate)
Ridged Foams will be Polystyrene, EPS (Expanded PolyStyrene: ice chest), or Polyurethane
Your first link to the green foam looks like a high density polyurethane, and is WAY TOO expensive for prop building.
Link #2 has ridged Polyurethane but I see no prices. The 64Kg/M^3 is roughly equal to 4lb/ft^3. This would be my choice.
2 lb foam is for armatures, where it is just holding space and will be covered in clay.
4 lb foam is good for sculpting forms and will hold its shape and fine detail
6 lb foam is still good for sculpting, and can be vacuformed right over it.
12 lb foam is closer to Balsa foam. it is pretty durable
20 lb foam is almost wood
hope that helps
My preferred building method is 4 pound ridged polyurethane. It shapes very quickly and doesn't dent too easy.