PURPOSE: To attach an adhesive evenly to a melton dumbbell and a core ball or a core ball alone preventing spillage thereof while reducing the drying time by a method wherein a heat sensitive gelling post-vulcanized latex adhesive is attached thereto, heated to gelatinize and then, dried.

CONSTITUTION: A molton dumbbell and a core ball or a core ball alone to which a heat sensitive gelling post-vulcanized latex based adhesive is attached is retained at the gelatinization temperature of 50W90°C for 1W10min to eliminate water by gelatinization. No vulcanization takes place at this temperature. Then, the core ball and the melton dumbbell or the core ball is dried at the room temperature.