Forming device for settable fluids for use in construction

A light-weight formwork system for molding elements from a settable material for use in the construction of buildings such that members which comprise mold walls for said settable material are precisely positioned, comprising:

• a set of light-weight members which, when assembled, form a structure for the forming of said settable material, said members having rectilinearly arrayed apertures therethrough, with selected apertures adapted to receive dowels and with other apertures adapted to receive oversized plugs, one of said members having a positioning and anchoring dowel projecting outwardly therefrom from a corresponding aperture, an aperture in an adjacent member adapted to receive said positioning and anchoring dowel;
• a set of oversized plugs in said other apertures to prestress said members when said plugs neck down to fit into the apertures into which they are inserted;
• and,
• means at an oversized plug in one member for coupling to an oversized plug in an adjacent member to couple together said members, whereby when said one member is mated to said adjacent member, it is self-aligned with said adjacent member due to the use of the rectilinear array of apertures in said members, the oversized plugs in said apertures to prestress said members to promote dimensional stability, and a positioning and anchoring dowel from said one member projecting into the aperture of said adjacent member, the system being self-aligning.