PURPOSE: To prevent the inclusion of voids and to reduce production cost by pushing an outer mold to the laminate on the outer periphery of a male mold- cylindrical part, applying tension to the outer mold, after the peripheral part of said outer mold is fixed to a base at the condition in which the outer mold composed of an elastic sheet is being pushed to the laminate on the outer periphery of the male mold-curved surface.

CONSTITUTION: A laminate 16 formed on a male mold 10 is covered with the outer mold 17 made of an elastic sheet. A reinforcing ring 18 is formed at the periphery of the outer mold 17. The outer mold 17 is fitted into a groove 12, applying required tension to the outer mold 17, and then it is vacuum-exhausted through an exhaust vent. The outer mold 17 pushes the laminate 16 at the outer periphery of a cylindrical portion 14, while pushing the laminate 16 at curved surface portions 15, and the cloths impregnated with resin is uniformly distributed therein. Consequently, while the voids included in the laminate are easily exhausted, the reliability of the product is improved, as the resin is uniformly distributed. Then, the production cost of the mold is reduced, as the outer mold is reduced, as the outer mold is composed of elastic sheet.