A method of making a molded article from two or more different formable materials having different molding temperatures in a single heating or molding cycle. One of the formable materials is selected as a reference material, and the remaining formable materials are modified so that all of the formable materials reach their respective molding temperatures at substantially the same time. Preferably, each of the remaining formable materials is modified by mixing a suitable amount of an additive therewith so as to adjust the power factor of the formable material. All of the formable materials arethen placed in a flow molding apparatus whereby an alternating dielectric field is applied across the formable materials to form the molded article.