a large surface shaped structure having a smooth surface is formed by compression molding a charge of reinforced molding material containing a thermoplastic material by placing a heated mold charge in a mold which has its peripheral surfaces spaced apart to provide a shear gap . the width of the shear gap is adjusted to accept a quantity of molding material sufficient to dissipate residual energy in the flow front of the charge to prevent rebound of the flow front as the structure solidifies .