Abstract: Low speed rotational molding of plastic objects at about ambient temperatures from a liquid thermosetting plastic material distributed in a mold substantially under gravitational force; the selected thermosetting plastic is placed as a distributable liquid in a mold having a volume much larger than the volume of the liquid polymer and slowly rotated about two axes at or about room temperature; urethane polymers to which a quantity of diamine curing agent has been added prior to the introduction of the flowable plastic into the rotatable mold are typical thermosetting materials; useful objects or shapes having thin, relatively uniform walls are produced by the disclosed process; repetition of molding steps allows the build up of same or different layers which may have interposed therebetween, lightening, stiffening, and/or strengthening members; precoating of a mold with a variety of coatings which release, interact, or decorate the thermoset resin surface is also disclosed.