Making your own molds for casting

[Russ Bellinis]

Josh, for concrete freeway type overpasses, scratch build your "bucks" and use styrene to make molds. They are all simple poured concrete shapes with no fine detail. If you want to make something with more detail like some of the art deco concrete arches seen in downtown Los Angeles or San Diego, to name a couple of cities not far from you, then you wold need to make models and use silicone molds.