Donut tooling mold structure and method

A method of molding a generally toroidal or donut-shaped article, comprising steps of:

• securing, in an injection molding apparatus, a stationary plate including a first mold cavity;
• securing, in an injection molding apparatus, a movable plate including a second mold cavity that cooperates with the first mold cavity to form a molded, one-piece, generally toroidal or donut-shaped article when the movable plate is moved against the stationary plate, and a material of the generally toroidal or donut-shaped article is injected into the opening formed by the two cavities;
• positioning at least one hollow-interior forming structure within the opening formed by the two cavities when the movable plate is moved against the stationary plate, but that is spaced from surfaces of the respective cavities to prevent the material of the generally toroidal or donut-shaped article from filling the space occupied by the hollow-interior forming structure and therefore form a hollow interior of the generally toroidal or donut-shaped article, wherein the hollow-interior forming structure includes an open section or gap comprising a radial cross section of the toroid or donut shape, and causing a gap-filling member that extends from one of the first or second mold cavities to fill the open section or gap when the injection molding apparatus is closed, and to vacate the gap when the injection molding apparatus is opened, thereby enabling separation and removal of the molded donut-shaped article from the hollow-interior forming structure upon completion of injection and opening of the injection molding apparatus.