Core materials are lightweight, structural layers used to produce high strength-to-weight ratio structures. As a key component of sandwich panel construction, core materials are “sandwiched” between layers of structural composite skins to offer greater strength properties than those of the skins alone. The process of separating the structural skins with a core material produces a much lighter structure than would be produced if solid composite materials were used. By increasing the core thickness, the stiffness of the sandwich panel is increased without substantially increasing the weight and cost.