Abstract: The invention provides a method for making a golf ball. Two cups are molded from an elastomer separately from an inner sphere. In one embodiment of the method, the cups are molded on both sides of a single mold part with hemispherical protrusions that form cavities in the cups. An inner sphere is placed within the cavities, and the cups are joined, by preferably crosslinking the cups together or applying adhesive there between. To retain the characteristics of the cup material where the cups meet, an embodiment of the cups can be formed with nonplanar mating surfaces that mesh with each other. The nonplanar mating surfaces preferably have a pattern that is symmetrical about the inner sphere, such as concentric ridges, for example a tongue and a groove.