Method for molding resin-product

A method for molding a resin product comprising the steps of:

• preparing a molding die, the molding die having a die cavity capable of defining a shape of the resin-product provided with a shaft bore extending along the central axis of the resin-product to a predetermined depth and with a bottom portion at one end thereof, a bar-like member having an axis thereof and disposed in the die cavity to define the shaft bore during the molding, a resin flow runner formed outside the die cavity so as to extend toward the die cavity on an extension line of the axis of the bar-like member, a gate sprue in continuation with a terminal end of the resin flow runner, and a gate in continuation to the gate sprue which is formed to fluidly communicate with the die cavity and to inject molten resin supplied from the resin flow runner into the die cavity, the gate having a diameter thereof smaller than that of the gate sprue, the bar-like member being located within the die cavity such that a length of distance from a top end face of the bar-like member to the gate is smaller than an extent of the gate diameter;
• solidifying the molten resin upon being injected from the gate into the die cavity through the resin flow runner;
• and
• forming a hole in the bottom portion of the shaft bore in the resin-product upon tearing off the resin, which is solidified in the resin flow runner, the gate sprue and the gate, in the vicinity of the gate, and also tearing off a resin portion of a resin-product member which connects to the gate when the resin portion is solidified in the die cavity together with the resin-product member.