Abstract: A method is described for the cutting of apertures in a material using a computer, laser control software, input device, laser and an x-y plotting bed. The method is to preferably form apertures in fluid impermeable material including composite materials. The apertures are used as exhaust valves in positive pressure masks to deliver breathable gas to patients and in garments.

Abstract: A brazable composite metal material for a heat exchanger tube or manifold, a method of making the tube or manifold, and a heat exchanger made therefrom. The composite metal suitable for making the heat exchanger tube or manifold has one of an aluminized carbon steel, galvanized carbon steel, or steel wire mesh core roll bonded to at least one outer layer of a brazable aluminum alloy, such as type 3003 aluminum alloy.

Abstract: A cookie cutter comprising (a) a silhouette formed in a desired shape and carrying a dough cutting shape at a front face; (b) a plaque formed to conform with the shape of the silhouette and positioned at a rear face of said silhouette, said plaque having an outer surface and an inner surface; and (c) a polymeric adhesive material positioned on an inside surface of the plaque and joining the silhouette and plaque together.

Abstract: A method of making a composite metal material comprising the steps of providing two outer layers of copper pre-bonded to a pure aluminum such as 1100 series aluminum or to an aluminum alloy such as 3003 aluminum alloy; providing a core layer of alclad aluminum, comprising a composite having a core of aluminum alloy pre-bonded to outer layers of substantially pure 1100 series aluminum; placing the outer layers of copper pre-bonded material on either side of the alclad core layer such that the aluminum layer carried by each copper layer is facing the alclad core layer to form a stacked pack; heating the stacked pack assembled in step (c) to a suitable rolling temperature, such as about 650° F.; and hot rolling the stacked pack in a rolling mill at incremental reductions to roll bond the layers to a desired finished thickness.