Abstract: A rotary casting apparatus for molding hollow articles of synthetic plastic is described employing a plurality of hollow molds which are heated and rotated within a fixed oven. The molds and molded articles therein are cooled rapidly while they remain within the oven by injecting cool, moist air into such oven from an external blower fan and a sprayer which sprays water into the air inlet of such fan. Improved rotation and support means are provided for the molds, including a common tubular drive shaft which rotates all of the molds about a common axis and a plurality of rotor means for rotating each of the molds about another axis perpendicular to such common axis. The rotor means are coupled by bevel gears to a second drive shaft extending through the common drive shaft. Each of the molds is rotationally mounted on bearings which are supported on the common drive shaft.