To provide a mold in which bareness is hardly generated in a tire, the flexibility of a shape is high, and the unevenness of the thickness of a base 24 is suppressed.

A plurality of first metallic pieces 26 are erected on a temporary base 34. These first metallic pieces 26 and the temporary base 34 are set in a mold. Molten metal is cast in this mold. A space between the first metallic pieces 26 and other first metal pieces 26 adjacent to the first metallic pieces 26 is filled with the molten metal. The molten metal is solidified, and a casting 42 is obtained. The base 24 and a second metallic piece 28 are formed by the solidification of the molten metal. A slit is formed between the first metallic piece 26 and the second metallic piece 28 by the solidification and the shrinkage of cooling. The casting 42 is cut, and blocks 44 are obtained. These blocks 44 are cut, and the pieces of segments are obtained.