Abstract: An improved phosphate-type refractory investment material and method for making solid investment molds especially useful for casting high melting point metals and alloys, such as platinum and the like. The material consists essentially of one or more phosphate salts, a water soluble acidic constituent, and refractory powder. The material can be prepared as a dry powder blend which is easily shipped to the user and mixed with water at the time of investing the flask. Alternatively, the salt and/or acidic constituent can be combined with the refractory powder at the time of mixing with water.

Abstract: An expendable and machinable pattern material capable of being cast in large blocks without shrinkage and machined to a casting shape useful in the lost pattern process of investment casting, the material consisting essentially of ethylene-vinyl resin, fatty acid ketone, and fatty acid.

Abstract: An improved phosphate-type refractory investment material and method for marking solid investment molds especially useful for casting high melting point metals and alloys, such as platinum and the like. The material consists essentially of one or more phosphate salts, one or more water soluble organic acids, and refractory powder. The material can be prepared as a dry powder blend which is easily shipped to the user and mixed with water at the time of investing the flask. Alternatively, the salt and/or organic acid can be combined with the refractory powder at the time of mixing with water.

Abstract: An improvement in the after-cast operation of removing the casting gate from an investment casting comprising a formed locator on the gate, the formed locator being capable of locating the casting in a desired position and of being gripped to hold the casting in place while the gate is severed near the casting. An investment casting pattern and gate attached thereto, the pattern gate being distinguished by a locator formation on the gate at a location spaced from the casting pattern.

Abstract: An improved refractory investment material for use in making refractory molds is provided. The material comprises an investment powder including a binder, a refractory selected from calcined mullite and pyrophyllite, additives for controlling setting and about 0.01 to about 0.04% by weight of a sulfate salt. The investment powder is formed into a slurry with a solution of a water based colloidal silica in an amount providing about 3% to about 6% by weight colloidal silica based on the weight of the water and a chloride salt in an amount of at least about 0.5% by weight based on the weight of said investment powder.

Abstract: An apparatus and method for automatically forming ceramic shell molds as part of an investment casting process. The apparatus includes structure defining a plurality of processing stations which together define a process line through which set ups are conveyed and coated with cermic material. The first station includes a pickup arm assembly operative to transfer a set up from a transfer cart to a slurry tank where it is released. A transfer arm forming part of a second station engages the set up rotates it within the slurry tank for a predetermined time, after which, the slurry transfer arm transfers it to a spin-off tank and releases it. A stucco transfer arm assembly forming part of a third station engages the set up and rotates it to spin-off excess slurry solution after which the stucco transfer arm transfers it to a stucco tank and releases it.

Abstract: Method and apparatus for producing ceramic shell molds characterized in that a plurality of pattern set-ups are arranged with their longitudinal axes transverse to an axis of rotation and are rotated as a group while applying fluent refractory material to produce either a multiple number of molds or a single mold. A ceramic shell mold characterized by a main sprue passage, a plurality of transverse sprue passages extending therefrom, and casting cavities gated into the transverse passages.

Abstract: A ceramic shell mold having the properties of being easily removed from the metal castings, high permeability, and a fired strength that can be controlled at levels lower than conventional molds, characterized in that the refractory used to make the mold is at least in part hydrated alumina.

Abstract: In the art of investment casting, a refractory mold characterized by a casting system including a sprue passage, a cup at one end of the sprue passage, a runner extending from the cup and connecting to the sprue passage near its other end, at least one pattern cavity gated into the sprue passage between the ends of the runner, and a refractory wall in the cup dividing it into a pouring cup portion communicating with the runner and another portion communicating with the sprue passage. A pattern set-up designed to make the mold by the "lost pattern" process of investment casting.

Abstract: Ceramic cores suitable for use in investment casting operations are molded from a mixture containing comminuted refractory which includes partially dehydrated gypsum and a sublimable binder. When the sublimable binder has been sublimated from the molded core, it is soaked in water in order to hydrate the gypsum and cause it to set.

Abstract: A method of producing cast metal tooling, especially injection molds or dies, characterized by the steps of making a thin walled, investment cast shell which defines the functional cavity surface of the tooling, and casting a suitable backing metal against the shell to form a composite die or mold structure.

Abstract: An apparatus for cutting off castings from investment cast set-ups comprising a mandrel assembly engageable with the inside of the center tree of the set-up to clamp it with its longitudinal axis in a horizontal plane, a vertically movable carriage support, a carriage movable along the support parallel to the longitudinal axis of the center tree, a cut-off assembly including a horizontal abrasive disc on the carriage, and structure permitting lateral adjustment of the cut-off assembly in a direction normal to that of carriage movement.

Abstract: A pattern assembly for use in the lost pattern process of investment casting characterized by a center tree or sprue member including a central stem and a plurality of laterally projecting collars spaced apart along the stem and united therewith to provide the surface area for gating the patterns, the cross-sectional size of the stem being greater than the projecting width of the collar, whereby the stem serves to form a riser.

Abstract: In the manufacture of non-ferrous investment casting molds, a new investment material composed of a gypsum binder and a refractory which is at least in part pyrophyllite.

Abstract: For use in making investment molds by the lost pattern process, a pattern material which is machinable and has the capability of being melted out of the molds without cracking them, the material consisting basically of an ethylene-vinyl resin and at least one fatty acid ketone.

Abstract: For use in the lost pattern process of investment casting, an improved pattern assembly of the type having a pattern supporting center tree or sprue member including a rigid tube surrounded by a sleeve made of a flexible material, characterized by longitudinally spaced, thin bands of pattern material extending around the sleeve at those locations where the patterns are to be attached.

Abstract: A method of making investment shell molds by the lost pattern process characterized in that a strand such as wire or the like is wound circumferentially about a pattern assembly in at least one location before it is coated with refractory material to form a mold shell. Thereafter, the strand is unwound to separate the shell into segments, each of which is usable as a mold.

Abstract: Method and apparatus are disclosed for cyclically metering charges of a granulated wax-like or resinous material from a bulk supply and feeding such metered charges into a heated, pressurized reservoir. Each charge of the granulated material is fluidized with a stream of air under pressure to insure flow of the granules. The stream of air also serves to pressurize the reservoir and prevent the escape of hot air therefrom. Cooling of the reservoir inlet to prevent agglutination of the granules also is contemplated.

Abstract: A pattern set-up especially useful for making prosthetic dental appliances is assembled by attaching a plurality of refractory casts to a support member so that adjacent casts along the length of the support member are circumferentially offset with respect to one another. The casts carry expendable patterns that are connected to the support member by gating systems laid down on faces of the casts. The support member has outward protrusions supporting the weight of the casts and may be formed by a plurality of segments fitted together in end-to-end relation.

Abstract: Method and apparatus are disclosed for cyclically metering charges of a granulated wax-like or resinous material from a bulk supply and feeding such metered charges into a heated, pressurized reservoir. Each charge of the granulated material is fluidized with a stream of air under pressure to insure flow of the granules. The stream of air also serves to pressurize the reservoir and prevent the escape of hot air therefrom. Cooling of the reservoir inlet to prevent agglutination of the granules also is contemplated.