Moulding Foam

Howzit guys. . .
In my Cat build I’ve done a mould based on the outer hulls of the Ghost train using balsa wood.
I’m not really happy with the shape I got so I am actually gonna try shape one out of foam.
The Prob is What is the Best Foam to use???
Any1 got any names or ideas of the stuff?
Shaun

Up here in the US - I use extruded (not expanded) polySTYRENE house insulation from local building center. Be sure not to use polyURETAHNE if you are going to cut with a hot wire. It is OK if you are using tools to cut/shape/sand.

Up here stuff is usully made by Dow Chemical (at least locally available) and can be pink, blue or gray. Once shaped, cover with 2 inch wide packing tape, then epoxy/glass and the glass hull can be removed once cured. Don’t use polyester resin - it will melt the foam.

Jean Margail (FR) on his Water Resist web site under construction sows a way to build foam without using a hot knife. Might want to look at the process before starting. I have my own hot-wire system set up and use the templates (bulkheads) on each side to cut to shape.