Coal Mine Railway - Imaginary B&O spur.

[TCWORLD]

For the foam, I mostly left it to expand as it wandted, and then carved it back. In some areas (mainly tunnel areas), I had to use shiney plastic to act as formers after the surface layer had dryed (It dries in stages - firstly it creates a surface film after 1/2 an hour - can shape it with formers at this point. After that the centre begins to expand and harden.).

It takes plaster very nicely aswell, which is excellent.