Patent ID: RE39714

Claim:
A process for abrading a surface by delivering a stream of a mixture of a pressurized gas and a powdered abrasive material to the surface, which process comprises (A) connecting a source of pressurized gas to a hand-holdable apparatus that comprises (a) a container-receiving member detachably attached to a container containing a powdered abrasive material; (b) a discharge nozzle for directing the stream of the mixture of the gas/abrasive material against the surface; (c) a first flexible conduit having one end in fluid communication with the discharge nozzle and the other end in fluid communication with the attached container through the container-receiving member, wherein the flexible conduit is removable, is releasably connected at each end of the conduit, and each end of the first flexible conduit has a collar that is snugly, releasably retained to align one end of the flexible conduit with the discharge nozzle and the other end of the flexible conduit with a line communicating with the container for the powdered abrasive material attached to the container-receiving member; (d) a second optionally flexible conduit for connecting one end to an external gas source and the other end to the container-receiving member for the abrasive material container; (e) a manually-operated pinch valve located between the discharge nozzle and the container-receiving member for pinching the first flexible conduit to regulate the flow of the mixture of the gas/abrasive material to the discharge nozzle; and (f) a housing for parts (a)-(e), (B) directing the discharge nozzle against a surface to be abraded, and (C) actuating the pinch valve to allow a stream of pressurized gas/abrasive material to impinge upon the surface for a time sufficient to abrade the surface.