Abstract: A novel structural member, such as a tennis racket frame, having an unusually high strength to weight ratio is provided comprising an expanded foamed plastic core integrally bonded to a shell comprising at least one layer of resin-coated unidirectionally oriented graphite fibers, the shell completely encasing the core at any transverse cross section of the structural member, said core comprising from about 25 to about 75 volume percent of a low density cellular filler material, such as chopped cork, and from zero to about 60 weight percent of a high density weight control material, such as barium sulfate.

Abstract: A dart body for a hand thrown dart is provided with a series of parallel circumferential grooves that provide improved resistance to slippage when the dart is propelled forward, but also provide an improved smooth release of the dart when it is released. This is accomplished with grooves shaped with a 90.degree.0 or acute angle juncture on the forward or thrust wall of the groove and an obtuse blended angle at the juncture of the aft or rearward wall of the groove with the dart body surface.

Abstract: A drill body for drilling solid metal and for finish boring having, at the working end, two or more replaceable, indexable, hard metal inserts dimensioned and spaced radially to cut equal volumes of metal. The inserts are retained in pockets by a headed screw with a through passage for a wrench. The outside insert is also shaped and positioned so the drill body may be shifted radially from the drilling axis and used as a boring bar.

Abstract: An improved roof drill bit and roof drill driving assembly which is characterized as a "hands off" type in which the drill, driver, and drill extension are designed and assembled to have a stability which enables the operator to avoid guiding the drill with his hands. An improved drill bit prevents plugging of the assembly when used with suction systems and provides a heavier wall construction. Special adaptors are provided for driving drills and drill extensions.

Abstract: An improved roof drill bit for use in mining operations in which a carbide insert is diametrically located in a cylindrical body and held on axial prongs in diametrically opposed quadrants of the body by a brazed connection; diverging axial holes for coolant are positioned in said prongs to open at the trailing side of the cutting edges of the carbide insert to flood the edges with coolant liquid and flush cuttings into the other quadrants. The coolant passages also pass near the brazed face of the insert to cool the body in this area and minimize softening of the braze. The bit shank and driving steel have cooperating axial grooves forming a passage for the coolant liquid to the bit body. The driving steel and bit body also have aligned chordal sides providing a passage for flushing drilling chips and fines toward the mouth of the hole.

Abstract: An improved drill bit for the mining field for use as a roof drill, tunnel drill, rock boring and highway construction, both as a rotary and a rotary percussion drill, which includes a drill head with a diametrical slot positioning a brazed cutting blade, the head having a male drive shank to interfit with a female driver tube and having a maximum axial passage in the driver shank which opens to large fluid passages leading to chip slash openings in opposed quadrants of the drill bit. The drill head position has a hexagonal base portion above the drive shank with circular guiding portions in opposed quadrants adjacent the chip slash quadrant pockets.

Abstract: An indexable, insert for single-point and multiple-point negative rake holding devices which convert the cutting point to a positive cutting geometry. The insert has straight descending and widening V-shaped grooves from each corner along the adjacent sides, each groove modulating into a low angle straight section which rises abruptly into a radial cross-ridge at the midpoint of the groove, the cross-ridge rising to a crest line below the plane of the resulting island created by the grooves around the insert.

Abstract: A polygonal insert of hard cutting material used in single and multiple toolholding means to receive the same, the insert comprising a wafer having conjunctive side walls lying in planes intersecting each other and parallel to the axis of the insert, one or more faces of the insert normal to the sides being depressed to form a peripheral ridge around the insert composed of a cutting land, either negative or positive, and downwardly extending walls to provide a polygonal recess on the face of the insert. A chip breaker insert with the same configuration as the basic insert with smaller lateral dimensions is provided to position selectively within the peripheral walls of the ridge to be clamped in place as a chip breaker. Also, a support anvil is utilized below the insert supporting the face within the ridge walls on the base of the recess in the cutting holder.

Abstract: A sealant system for multiple part drilling components utilizing water as a coolant and flushing medium which includes nipple-like sealing inserts to interfit with axial recesses and with other opposed inserts to seal the axial passages extending through the joined axially aligned parts, each insert having a sealing relation to an axial passage in which it is carried and projecting into an adjacent part to interfit therewith.

Abstract: An improved drill bit for the mining field for use as a roof drill, tunnel drill, rock boring and highway construction, both as a rotary and a rotary percussion drill, which includes a drill head with a diametrical slot positioning a brazed cutting blade, the head having a male drive shank to interfit with a female driver tube and having axial passages leading to chip slash pockets for removal of chips either by incoming pressure fluid or outgoing suctioning action. The supporting prongs of the drill head on opposite sides and at opposite ends of the blade are narrowed in thickness to provide chip clearance and designed to overlap centrally to provide tip strength and central support for the blade.

Abstract: An electrical contact material which is particularly well suited for use in circuit breaker switches consisting essentially of silver in the amount of about 20% to 50% by weight, nickel in the amount of about 2% to 13% by weight, phosphorus in the amount of about 90 ppm to 1000 ppm, and the remainder tungsten. In one embodiment of the contact material forming method provided by the invention, starting particle sizes and liquid phase sintering parameters are selected to yield a relatively coarse grain size in the contact material microstructure with an optimum combination of resistance to oxidation, electrical erosion and distortion associated with high-current interruptions.

Abstract: A novel structural member, such as a golf club shaft or other tapered tubular member, having an unusually high resistance to torsional deflection for given desired longitudinal deflections along with high strength and a center of gravity more favoring the tip-end is provided by a resin-bonded graphite fiber structure in which the fiber orientations in each layer of the multi-layer, composite structure are varied along the length of the shaft and in desired orientation relationships between layers to achieve the unique combination of properties.This structural member is prepared by helically placing fiber yarns such as graphite onto a resin-coated, tapered steel mandrel by winding a series of high modulus graphite yarns in series of layers and progressively varying the rotational speed of the rings carrying the spools of the graphite fiber yarns in each layer as the mandrel is fed at a constant speed.

Abstract: A method of producing tantalum or columbium powder is described for producing a selected desired particle size powder under controlled conditions with a high rate of production and yield of usable powder. A molten salt bath of an alkali metal tantalum fluoride or an alkali metal columbium fluoride and a relatively large amount of diluent salt to act as a heat sink is initially maintained at a low temperature in the liquidus range, an addition of liquid alkali metal reducing metal is added at a very fast rate to the continuously stirred bath to create a rapid temperature rise to the reaction temperature, and liquid alkali metal is thereafter fed at a fast rate to complete the reaction quickly at the final reaction temperature. Cooling is used for at least a portion of the reaction cycle at a rate sufficient to maintain the final reaction temperature within a desired range.

Abstract: Improved, high-purity agglomerated tantalum powders having an exceptional combination of a relatively low oxygen content, high green strength when pressed into compacts without using any binders, and, when compacted and sintered as anodes for capacitors have reduced shrinkage of the pressed compacts during sintering, and have high electrical capacitance and breakdown voltage along with low direct current leakage and low dissipation factor. Such powder is produced by milling hydrided high-purity tantalum metal ingots to a powder of specified particle size and size distribution, subjecting the powder to a heat treatment at a temperature T-1 to degas and preagglomerate it, milling and screening the degassed and preagglomerated powder to preferably about -200 mesh size, subjecting the -200 mesh powder to a higher temperature T-2 to reagglomerate it, milling and screening the reagglomerated powder to about -35 mesh, and blending the final powder.

Abstract: Thin liners and tubes of special metals and alloys such as tantalum bonded to substrates or mounted in support plates of metallurgically dissimilar metals and alloys such as mild steel by an elastomer such as a silicone or fluoro elastomer. Also a shock absorbent mounting of tubes telescoped into heat exchanger tubes of special metals by elastomer cushions interposed between the tubes.

Abstract: A novel fletching assembly for darts having an exceptional design to allow darts to be placed in the target in close proximity with a minimum tendency to displace the flights of previously thrown darts, and to cause minimum deflection of other thrown darts is provided by securing the flight assembly by three or more pins with rounded heads and portions of their shanks securing the individual flights, and with the leading end of the pins secured in a hole in the dart fletching body and maintained in close tangential juxtaposition by means of a heat shrinkable tube encasing the cluster of pins from the front end of the dart flights forward onto the outside diameter of the aft end of the dart fletching body.

Abstract: A novel structural member, such as a tennis racket frame, having an unusually high strength to weight ratio is provided comprising an expanded foamed plastic core integrally bonded to a shell comprising at least one layer of resin-coated unidirectionally oriented graphite fibers, the shell completely encasing the core at any transverse cross section of the structural member with a veiling strip wrapped around said core beneath the innermost or beyond the outermost of the graphite fiber layers, or both.

Abstract: A novel structural member, such as a tennis racket frame, having an unusually high strength to weight ratio is provided comprising an expanded foamed plastic core integrally bonded to a shell comprising at least one layer of resin-coated unidirectionally oriented graphite fibers, the shell completely encasing the core at any transverse cross section of the structural member, with a seamless sleeve made of a thin, flexible cellulosic film between the core and the shell.The structural member is prepared by arranging within a mold cavity an outer shell comprising at least one sheet of resin-coated unidirectionally oriented graphite fibers and a core comprising a foamable resin composition while the core is maintained within a seamless sleeve made of a thin, flexible cellulosic film, sealing the mold cavity and activating the foamable resin composition to cause expansion and generate pressure within the mold cavity and thereby provide intimate bonding of the core to the shell.

Abstract: A novel structural member, such as a tennis racket frame, having an unusually high strength to weight ratio is provided comprising an expanded foamed plastic core integrally bonded to a shell comprising at least one layer of resin-coated unidirectionally oriented graphite fibers, the shell completely encasing the core at any transverse cross section of the structural member, said core comprising from about 25 to about 75 volume percent of a low density cellular filler material, such as chopped cork, and from zero to about 60 weight percent of a high density weight control material, such as barium sulfate.

Abstract: A transparent gauge for use in accurately checking and setting the height and angular position of tool holding blocks utilized for the holding of tools for the cutting of coal, rock and the like. The device consists of a basic support sheet adjustably supporting a tool block indicator silhouette sheet movable arcuately relative to a sheet bearing angle indicia, all of which can be placed adjacent an actual tool to check angles and to set angles.