Abstract: A improved method of manufacturing plastic containers with molded-in metal inserts is employed to secure metal inserts to an interior of a rotary mold so that the inserts are automatically released from the mold when the article is removed from the mold. The method includes providing a mold having a magnet on the interior surface thereof, placing a metal insert in contact with the magnet, charging the mold with a quantity of a resin, biaxially rotating and heating the mold to melt and distribute the resin, cooling the rotating mold and removing a finished container with a molded-in metal insert. The mold rotates biaxially, about a first axis and a second axis which is perpendicular to the first axis. Preferably, the mold is constructed with magnets projecting from the outside through to the inner surface. The magnets present a concave curvate inner facing surface which mates with a convex curvate outer surface of a metal insert.