Abstract: In a method for producing large structural components such as boats or swimming pools of fiber reinforced synthetic materials layers of pre-impregnated fiber material are continuously applied to a mold. An air impermeable foil or membrane is sealed over the layers of pre-impregnated fiber material. The air is evacuated between the foil or membrane and the fiber material to press the latter by atmospheric pressure against the mold to cause the material to conform to the shear surfaces of the mold. The layers of pre-impregnated fiber materials are then heat cured by heated mats, for example, similar to electric blankets. The sheer surfaces of the molding apparatus are made of sheet material such as sheet metal or sheets of synthetic material. The pressure application and heat curing takes place sequentially in area after area whereby the final size of the finished structure is not limited by the size of an autoclave nor is it limited by the size of available heating blankets.