Abstract: An improved mass production assembly line is provided for fabricating building walls and similar structural members in molds by applying a hardenable polyester film to the cavity surfaces of mold halves, joining the mold halves and then introducing a mixture into the mold cavity to form a polyurethane foam.First and second rectangular fields of rollers, each mounted on a pedestal, are adapted to carry respective mating halves of each mold in a horizontal plane from a start end of the fields to the terminating end. The mold cavities face upwardly. The lower surface of each mold half has secured thereto elongated T-shaped bars. The bars are parallel with each other, and each bar is adapted to be carried by one line of rollers in a respective one of the fields. The parallel axes of the rollers are set to an exact height by means of a laser light source and photoresponsive means so that the upper edges of the rollers lie in the same horizontal plane.

Abstract: A clamping assembly is disclosed to hold walls and the like in position during construction of housing. The assembly is located and supported by a base which is held in place by nails driven into the floor. An upright beam held by the base is keyed at a location above the walls being held together to a rod connected to a vise unit. The vise is manually closed around one of the walls being joined. Movable jaws spaced along the upright beam are manually moved into contact with the other wall. The assembly is economic, effecient, and adapted for reuse.