[Gdeaver]

There is nothing wrong with wood. I "wood" suggest birch plywood. The wheel can be built up from several layers. To go a step further and build some really tough structures, laminate the plywood with 4 oz s2 fiberglass cloth. Use a good laminating epoxy. Our team has used wood, epoxy and fiberglass for several years now. Easy, tough, strong and cheap. Our shooter was made out of 3/4 birch plywood and was built in one night. If you want to try the fiberglass thing, let me know and I'll post some sources and info links. the RC airplane forums are a good place for composite construction info.