Re: Can you help?...suitable foams
I take it you're talking about lost foam casting, then? If so, you'll want to use EPS (expanded polystyrene, AKA Styrofoam), which burns out better than polyurethane. The trade-off (there's always something, eh?) is that you can get polyurethane in smoother, higher densities than EPS, which is not to say EPS can't be had in high density, either. The thing is, the greater the density, the higher the price, too. You shouldn't have any trouble finding either in Australia.