Patent US 4,495,013

A plastic foam-forming mixture (31), e.g. a polyurethane or polyisocyanurate foam mix, deposited from one or more static dispensers (19) is metered through two spaced opposed members 14 and 18 forming between them a metering gap. At least one of the members is deformable in a controlled manner such that the profile of the metering gap can be variously defined. Reduces "crowning" of foam boards while permitting foam boards of different thicknesses to be made without having to replace metering bars.