WORKING WITH EXPANDED POLYSTYRENE

IT'S VERY MESSY!

Making things with expanded polystyrene can generate a surprising amount of mess, especially once you start cutting it. Polystyrene crumbs get everywhere and stick onto everything. When you're modeling with expanded polystyrene, try and do your cutting somewhere that can be tidied up easily afterwards, like the garage, a shed, or the kitchen.

USE THE RIGHT SORT OF PAINT & GLUE

It's very important to use only water-based paints and glue for polystyrene, as solvent-based products can make it melt. Citadel Colour paints (the ones in pots) are perfectly safe, but not the sprays. Use only PVA glue: superglue and liquid poly will make the polystyrene melt! So how do you paint large areas of expanded polystyrene? To get around the problem at the Studio, we coat large models with textured masonry paint before undercoating with spray paint. The masonry paint covers and seals the polystyrene, so it doesn't melt when it's sprayed. The grainy texture of the masonry paint gives a realistic texture to the model's surface too.

BASING

Polystyrene is light and fragile, so to give your scenery some weight and strength, we recommend basing polystyrene scenery on a firmer, tougher material such as thick cardboard, foam card, or a thin sheet of wood.

CUTTING POLYSTYRENE

You can cut expanded polystyrene with a modeling knife, but doing so can be hard work if the polystyrene is thick, or you've got a lot to do. If you're going to do a lot of modeling with polystyrene, it's well worth investing in a terrain cutter (also known as a hot wire cutter). The canister contains a couple of batteries that heat a short length of wire, which allows you to slice effortlessly through polystyrene. The hot wire leaves a much smoother cut than a knife.

More about using a terrain cutter