Help with papier mache?

I always preferred to use something I could form myself, like foil, or could remove later, like a balloon. If you need a form that can only be done in Styrofoam, sure, use it.

There are all kinds of things you can use as "permanent armatures" under papier mache (or under various kinds of clays, etc). Which you might use could depend on the size and strength you need, the materials you have, what you want the sculpt to look like, cost, and more.

Polystyrene foams are fine but papier mache and other materials that "dry" will take longer to dry on those than on porous materials or ones with "holes" since the only air reaching the papier mache will be on its top side and drying will have to proceed only from that outside into deeper layers.

You might want to check out my answer here for more on possibilities:

http://answers.yahoo.com/question/index?qid=201101...

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