A braided, open structure composite made with large prepreg tow can be cured without bonding at the yarn crossovers and after removal from the mandrel, it can be used directly as a spring in which the spring constant in bending, torsion, tension or compression can be controlled by the geometry of the braided structure as well as the size of the structural elements. Alternatively the spring may be curved in multiple directions to form complex shapes and then crossovers can be re-bonded to make more rigid open structure composites that would be difficult or impractical to manufacture by conventional techniques.