Abstract: An apparatus for measuring the height of a solder wave having a supporting horizontal member, at least one elongated pin slidably affixed to the horizontal member extending vertically downward. The elongated pins have a sensing means affixed to it and the sensing means communicate with and indicator means to notify a technician the height of a solder wave relative to the top surface of the solder pot. The elongated pins with sensors attached thereto are set up to notify a technician if the solder wave is too low, too high, or at an optimum level. A screw and nut provide height adjustment for the elongated pins.

Abstract: A mold for joining conductors such as stranded cable to each other and to other elements such as a ground rod is formed of two or more parts. The mold formed by the parts includes a weld chamber. Exothermic welding material in a crucible above forms molten metal which drops into the weld chamber through a tap hole. The mold includes sleeving passages extending upwardly at an angle from horizontal to exit the mold well above the level of molten metal forming the weld. The sleeving passages extending upwardly at an angle from the weld chamber, or as a V with two symmetrical passages, are preferably larger than normal passages and accordingly will accommodate a wide variety of cable sizes without interference with or abrasion of the sleeving passages. This enables one mold to accommodate more sizes, avoids the use of packing, adapter sleeves or shims, and maintains the weld chamber well vented.

Abstract: A method of depositing solder paste includes the steps of: superimposing a masking member having a plurality of through-holes and a supporting member on each other so that the supporting member covers the plurality of through-holes; filling cavity portions formed by the plurality of through-holes and the supporting member with solder paste; disposing an LSI chip and the masking member so that electrodes and the cavity portions are superimposed on each other respectively; and heating the solder paste so as to make the solder paste deposit on the electrodes.

Abstract: The invention features soldering parts (e.g., printed circuit boards) by indexing the parts sequentially and continuously through a series of processing stations. Each of the series of processing stations includes at least one processing position, and the indexer indexes the parts from processing position to processing position. At different processing stations, the parts indexed into those processing stations are simultaneously processed.

Abstract: A method and apparatus enables the securing of balls to ball grid array electronic components. A component having a surface with rows and columns of electrical contact pads is removed from a printed circuit board for rework. Excess solder is removed from the pads and the surface is pressed against a stencil having a pattern of holes corresponding to the component contact pad pattern. The holes are filled with a paste continuing flux and solder particles. The assembly is heated to melt the solder particles, which agglomerate into generally spherical balls bonded to the contact pads. The assembly is cooled, the stencil is removed, the component is cleaned and is ready for reuse. Preferably, the stencil is formed from a material that bows in one direction when heated, so that when the stencil is held against the pad array surface and heated, bowing forces will very tightly press the stencil against the surface, preventing molten solder from migrating between surface and stencil.

Abstract: An apparatus for depositing a selected pattern of solder onto a substrate on which electronic components are to be mounted. The apparatus includes a substrate support, a replaceable solder cartridge, and a solder ejector. The replaceable solder cartridge defines a cavity for containing solder and has an orifice for ejecting a continuous stream of molten solder. The solder ejector has a mechanism for retaining the replaceable solder cartridge during solder deposition and is positioned relative to the substrate support to deposit molten solder ejected from the orifice of the replaceable solder cartridge onto the substrate.

Abstract: An apparatus for depositing a selected pattern of solder onto a substrate comprising: a substrate support having structure for bearing a substrate on which one or more electronic components are to be mounted; a solder ejector that defines a cavity for containing molten solder and an orifice for ejecting a stream of molten solder; a heater for heating the solder to a temperature above the melting point of solder; a vibrator coupled to the solder ejector to form droplets in the stream at the desired frequency for deposition onto the substrate; and a cooler, adapted to receive a coolant, disposed between the heater and the vibrator to maintain the temperature of the vibrator below that which would detrimentally affect the performance of the vibrator.

Abstract: In order to produce separate measured portions (1") of liquid solder, solid solder (1) in the form of wire or rod is guided through the longitudinal bore of a guide tube (20). A zone including the end (22) of the tube (20) is heated above the solder's melting temperature, in order to liquefy the solder. By contrast, an adjacent zone of the guide tube is cooled, whereby a positionally stable temperature transition is maintained in the tube (20). Thereby the amount of molten solder available above a narrowed outlet (62) is controlled. A drive mechanism (3) advances the solder (1) step by step so that the solid solder acts as a piston to eject portions of liquid solder through the aforesaid outlet (62). A suitable apparatus (5) for applying portions of solder to a substrate (4) can be raised and lowered (a). At its base it has a moulding die (6) connected to the outlet (62) that can be set down upon the substrate and has a moulding cavity open on its underside.

Abstract: The placement of solder "balls" in a Ball Grid Array is accomplished by placing a solder strip in contact with the top surface of the ball grid array carrier. The pulsing of a laser directed at the solder in discrete positions permits the transfer of the solder to the gold dot, of the array of dots, on the carrier in registry with the laser output when activated. Selective solder placement is possible and increasingly higher throughput is achieved by the use of laser diode bars or optical fiber fans to effect solder transfer to a plurality of dots of the array simultaneously. The entire process can be automated by making the solder strip continuous through a recycling station arranged along a path along which the solder strip moves to the position where the carrier and the solder strip are moved into juxtaposition. The use of a transparent strip with a pattern of holes filled with solder paste permits easy transfer of the solder to the gold dots or islands on the carrier in registry with laser beam.

Abstract: In order to reduce the residual stresses which occur in the region of a fusion weld of two rail ends (1,2), in order to reduce, in particular to make uniform, the cooling-down rate and--associated with this--the crystallization process within the solidifying weld material, a casting mold is proposed which is equipped with a system of risers (9) and air vents (10) which are designed symmetrically with respect to a longitudinal center plane (5) and a transverse center plane (3) of the welded joint, the risers (9) and the air vents (10) being physically distributed as a function of geometric parameters of the rail foot (8) and of the weld bead (4), and the cross sections of the air vents (10) being dimensioned as a function of the cross sections of the risers (9).

Abstract: A material (21) is transferred to an electronic component (32) using a transfer apparatus (10). The transfer apparatus (10) has pins (13) that pass through openings (19) in a cavity plate (16). The pins (13) and the openings (19) in the cavity plate (16) form cavities (20) that are filled with the material (21). The pins (13) are then extended from the cavity plate (16) to transfer the material (21) from the cavities (20) to the electronic component (32).

Abstract: An inert gas air horn distribution device employs a labyrinth with a baffle to clean the nitrogen gas used to deposit flux on circuit boards before wave soldering operations. The baffle diverts the gas flow causing heavier flux particles to collect in the labyrinth while the lighter gas exits for use in depositing flux on the circuit boards. The labyrinth cleans the gas thereby keeping the knife clean which produces more uniform results with less maintenance.

Abstract: An apparatus for dispensing solder includes a nozzle body having a plurality of flow channels formed therein. Each flow channel includes an inlet end and a dispenser end for dispensing solder. The nozzle body forms a nipple surrounding each dispenser end, and the nozzle body further forms a shielding chamber in communication with each dispenser end for protecting the respective nipple, and optionally providing flow of inerting gas and/or excluding ambient oxygen from the soldering area. The nozzle bodies comprise micro-machined silicon. Various flow channel configurations are provided for improved flow characteristics.

Abstract: A solder dispensing apparatus for depositing fluid solder into and around a pin-in-through-hole joining zone of an electronic circuit board which comprises:a valve assembly defining a valve chamber with an inlet and an outlet, and having the valve member actuated by the pin of said pin-in-through-hole joining zone when the valve is positioned at the zone against the board, the valve member moving from a first position closing off fluid flow from the outlet to a second position permitting fluid flow through the outlet; means for measuring a predetermined body of fluid solder that is released from the chamber when said valve member is in the second position with the assembly positioned at the zone against the board; and means to contain the released fluid solder in a predetermined shape and in and around the pin-in-through-hole joining zone while the solder solidifies.

Abstract: An integrated circuit (IC) package includes solder paste inter-layer and alignment apparatus 100 for applying and aligning solder paste 150 with corresponding solder pads 160 on the IC package carrier 200. The apparatus 100 includes a thin layer 100 which is composed of high-temperature-resistant, non-solder-wetting, and electrical-insulating materials. The apparatus further has a plurality of apertures 110, each disposed on and penetrating through the thin layer 100 for applying solder paste 150 therein and for aligning with the corresponding solder pads 160 on the IC package carrier 200. The apparatus 100 further includes a removable thin film tape 120 disposed on a bottom surface of the thin layer 100 for temporarily maintaining the solder paste 150 in the plurality of apertures 110.

Abstract: A dispensing apparatus for applying a pulsed thin stream of flux to a surface such as a printed circuit board. The stream of flux is pulsed at a high rate to apply a thin layer of flux on the surface. The dispensing head consists of multiple orifices for applying the flux to the board. The streams of flux are angularly disposed and a pan is positioned for capturing flux which passes by the board. The board is conveyed by the dispensing head. Controls are incorporated for board sensing and identification, application width selection, precise pressure control, fluid flow monitoring and system safety conditions.

Abstract: The improvement in the soldering method comprising the steps of feeding a predetermined volume of solid solder to a solder melting pot, heating and melting the solder in the pot, and then dropping the molten solder onto a workpiece. A wire solder is held between at least one pair of endless running belts which run with opposed faces thereof in contact with each other thereby to straighten the wire solder. The tip-end of the straightened wire solder is pressed against the solder melting pot to melt the wire solder from the tip-end. On completion of feeding a predetermined volume of the wire solder, the running belts are run in reverse to retreat the tip-end of the wire solder from the solder melting pot. A soldering apparatus for realizing the aforementioned method is also provided.

Abstract: A multichip module is assembled using flip-chip bonding technology, a stencil printable solder paste and standard surface mount equipment for interconnecting signaling input/output contact pads on devices within such a multichip module. The disclosed assembly process makes the heretofore difficult and expensive flip chip bonding technique achievable at low cost. The flip chip bonding technique is simplified by use of a solder paste which includes desirable reflow alignment, fluxing and printability characteristics. These desirable characteristics allow the assembly process to be further economically achieved by permitting the use of standard surface mount equipment in the process. High volume production of standard inexpensive modules are thus possible through this process while also achieving the advantage of high density interconnections afforded through the flip-chip bonding technology.

Abstract: Exothermic welding apparatus includes a toggle frame jig for supporting vertically split molds. The toggle includes a post projecting parallel to the main pivot of the jig on which telescopes a crucible support. The crucible support includes a handle extending above the crucible when secured to the support. A quick acting toggle connects the support and post enabling the crucible to be assembled, cleaned, or prepared remote from the molds and then quickly installed and locked in position.

Abstract: A fluxless soldering sample pretreating system includes a sample chamber having an opening therein and a sample holder. A sample chamber extension extends outwardly from the opening to define a passageway from the sample chamber extension, through the opening, and into the sample chamber. A fluorine-containing gas is supplied into the sample chamber extension. Am energy source such as a microwave oven surrounds the sample chamber extension. The microwave oven produces microwave energy in the sample chamber extension to form a plasma therein and dissociate the fluorine-containing gas into atomic fluorine. A perforated aluminum plate extends transversely across the passageway and blocks the plasma from traversing the passageway from the sample chamber extension into the sample chamber, while allowing the atomic fluorine to traverse the passageway from the sample chamber extension into the sample holder.

Abstract: A needle has an inner passage for applying viscous fluid. A filter having a plurality of minute perforations is provided in the needle, whereby the fluid enters the inner passage through the filter.

Abstract: An improved soldering machine for automatically soldering links of a chain is provided in which the links are disposed adjacent to one another and define link junctions where the improved soldering machine holds the chain in position to enable the link junctions to be soldered. A soldering device applies solder paste to the chain at the link junctions by feeding the solder paste through a hollow needle having a needle tip wherein the needle tip traverses a predetermined path and contacts the chain over a portion of that predetermined path. The improvement consists of a heater which traverses a cyclical path which is dependent upon the position of the needle tip and heats the solder applied to the chain over a portion of that cyclical path.

Abstract: A feed device for a soldering iron possesses a coil through which current flows, located in the soldering iron itself, and an armature that is displaceably driven in the central bore of the coil. This armature cooperates with a clamping device connected to it. Thus, an intermittent clamping and feeding action may be effected in the clamping device. Such a device is space saving and has substantially no parts subject to wear.

Abstract: Apparatus and methods for a system and process for applying a flux coating to a circuit board by pulsing an airless spray gun on and off to achieve excellent circuit board through-hole penetration and uniform film thickness. An overspray collection system is provided which reduces overspray and increases material utilization and transfer efficiency. A gun positioning mechanism, which can be automated, accurately locates the gun relative to the circuit board.

Abstract: A micro soldering apparatus and method comprising a system (10) for attaching an electronic component (12) to a substrate (14). The system (10) comprises a soldering tool (16) including a dispensing orifice assembly (18) for pulsatingly dispensing a controlled quantity of molten solder (19) to a component (12) and substrate (14) so that the component is joined to the substrate (14) mechanically and electrically upon solidification of the molten solder (19). There is no physical contact between the dispensing orifice assembly (18) and joint. The system (10) also includes a controller for the soldering tool (16). The controller functions in response to process control parameters so that the controlled quantity of molten solder (19) is dispensed through a non-oxidizing atmosphere by a pressure pulse applied to the molten solder.

Abstract: A dispenser for applying creamy solder onto a substrate, comprising: a syringe 1 storing therein creamy solder; a needle 2 fixed at the forward end of this syringe 1; and a driving mechanism 3 using a pulse-controlled stepping motor and an eccentrically rotating drive motion. The driving mechanism 3 comprises: a linear guide 10 for guiding a syringe holder which holds the syringe 1, a stepping motor 11, a crank 13 and a connecting rod 14 rotatably supported on the crank and the syringe holder. When, the stepping motor 11 is rotated by a predetermined angle, the crank 13 and the connecting rod 14 are eccentrically rotated in an interlocking relation to the rotation of this stepping motor, and the syringe 1 is upwardly and downwardly moved within a predetermined range through a syringe holder 9.

Abstract: Apparatus for installation of honeycomb core seals in jet engine mounting rings, including spray deposition of brazing alloy in seals and establishment of compressive relationships between seal and ring prior to brazing of seal in ring.

Abstract: A dispensing apparatus for applying a thin stream of flux to a surface of a printed circuit board. The dispensing head travels at a high rate of speed relative to the board during the dispensing of flux to apply thin layers of flux thereto. Preferably, the dispensing head moves transversely to the work path of a conveyor that transports the board through a flux station, at a rate of approximately 20 to 90 inches per second. Tips that dispense the flux are angularly disposed relative to the board and, if desired, make multiple passes over the surface to coat selected regions twice. Either the board is incrementally advanced through the flux station or the dispensing head is incrementally advanced relative to the board so that flux is applied when the board is stationary.

Abstract: A gas flow distribution system for a solder dispensing head includes a base member adapted to be connected to the solder dispensing head and a structure connected to a source of an inert gas for distributing at least one continuous stream of the inert gas radially and axially below the solder dispensing head to exclude oxygen in the surrounding air therefrom.

Abstract: A system and method for manufacturing an article that is formed by the incremental buildup of layers on a work surface contains a material deposition station to deposit the layers. In addition, a plurality of processing stations are employed. Each processing station performs a separate function such that when the functions are performed in series, a layer of the article is produced and is prepared for the deposition of the next layer. An article transfer apparatus repetitively moves the work surface and any layers formed thereon selectively among the deposition station and the processing stations. The article transfer apparatus continues to move between the processing stations until each layer is processed and a completely manufactured article is produced.

Abstract: The improvement in the soldering method of soldering a workpiece comprising the steps of forming a solder melting pot by engaging plural trowel members, supplying a solder tip having a constant volume to the solder melting pot, melting the solder tip and holding the molten solder temporarily in the solder melting pot and then separating the plural trowel members to allow the molten solder to drop onto the workpiece. The improvement comprises detecting complete melting of the solder tip by sensing the change in intensity of the light reflected by the surface of the molten solder, and heating the molten solder for an additional time period after the completion of melting of the solder tip. A soldering apparatus for use to realize the aforementioned method is also provided.

Abstract: A bump having a shape adapted to bonding of a flip chip method and an enough volume is efficiently accurately formed at low costs. By applying a pressure into a chamber, a fused solder 8 in the chamber 1 is extruded from a micro opening 3 and adhered onto a pad 12. After that, by eliminating the pressure, the fused solder is separated by the surface tension of the fused solder itself and is allowed to remain as a solder bump onto the pad.

Abstract: Metallic surfaces are soldered together without using flux or solvents. The metallic surfaces are maintained in an atmosphere of inert gas and cleaned with a laser. An ejection device deposits drops of liquid solder on a predetermined one of the metallic surfaces and the metallic surfaces are moved relative to each other so that the solidified solder contacts the other metallic surface. The metallic surfaces and the solidified solder are then heated until the solidified solder reflows and joins the metallic surfaces.

Abstract: In the method for forming through-holes of the present invention, by injecting a conductive material into the through-holes by means of a filling nozzle while removing the excessive conductive material with a squeegee, the filling can quickly and uniformly be performed independently of the board thickness of the substrate and the number and diameter of the through-holes.

Abstract: To achieve the above object, the invention provides a novel method of filling through holes of a printed wiring board with conductive filler material by initially feeding compressed air to the conductive filler material by initially feeding compressed air to the conductive filler material across mask in the direction of through holes so that pressurized conductive filler material can be filled into through holes from a conductive-material extruding nozzle unit.It is suggested that such silk screen be used for the mask, which is provided with through holes at positions corresponding to the positions of these through holes of the printed wiring board.

Abstract: A dispenser (100) for solder flux includes a first solder flux reservoir (110) with a dispensing tip (118) at one end thereof for dispensing solder flux (112) in response to a frictional pressure applied to the tip. A second solder flux reservoir (102) is also included having a dispensing channel (106) for dispensing solder flux (104) responsive to a pressure applied to the flux (104) within the second solder flux reservoir (102).

Abstract: A nozzle assembly is shown for depositing solder onto a series of conductive surfaces such as the mounting pads of a surface mount integrated circuit board. The nozzle assembly includes a nozzle head which has an interior bore for receiving an elongate heat source. The nozzle head also includes an orifice for receiving solid solder fed within the interior bore to contact the elongate heat source. The interior bore terminates in a solder reservoir for molten solder which is fed within the inteiror bore to contact the elongate heat source. The molten solder is dispensed through a tip opening to deposit uniform amounts of solder on each pad. A source of bleed gas is supplied to the interior of the assembly to protect the component parts and excluse oxygen from the interior of the assembly. A cover gas is also supplied to the solder site to reduce oxidation of the moltent solder and reduce the amount of flux required.

Abstract: A nozzle assembly is shown for depositing solder onto a series of conductive surfaces such as the mounting pads of a surface mount integrated circuit board. The nozzle assembly includes an upper nozzle mount and a removeable nozzle head which has an interior bore for receiving a portion of the nozzle mount and an elongate heat source. The nozzle head also includes an orifice for receiving solid solder fed within the interior bore to contact the elongate heat source. The interior bore terminates in a solder reservoir for molten solder which is fed within the interior bore to contact the elongate heat source. The molten solder is dispensed through a tip opening to deposit uniform amounts of solder on each pad.

Abstract: A method of applying molten solder onto a desired point of a small workpiece, such as a printed circuit board, under well-controlled condition. A solter tip is temporarily held above a solder melting pot and then allowed to fall into a solder melting pot in which the solder tip is melted and held for a pre-set time duration. In this manner, the scattering in velosity of the falling solder and the dislocation of the fallen tip are minimized to control the temperature of the molten solder precisely. A soldering apparatus used for the practice of the method of this invention is also provided. In a preferred embodiment, the soldering apparatus is provided with means for removing the debris sticking to the inner face of the solder melting pot.

Abstract: Apparatus and a process are disclosed for cleaning and/or fluxing circuit card assemblies. The assemblies are moved through an enclosure in which they are sprayed with cleaning and/or fluxing liquid from fenestrated cylinders rotating above and below the path of the assemblies and disposed laterally thereacross. The complex spray impact pattern created by the simultaneous movements of the assemblies and the cylinders effects thorough cleaning and/or fluxing of the assemblies. Separate control of liquid pressure from the cylinders prevents unsoldered components from being dislodged from the assemblies during cleaning and or fluxing.

Abstract: A method and an apparatus for solder plating parallel arranged leads on an electronic device, e.g. QFP having leads on four sides or SOLC having leads on two sides. A metal plate of solder wettable material having an inclined upper surface is placed in a molten solder bath. The electronic device, with the leads to be solder plated exposed, is lowered horizontally in the solder bath and is pulled out horizontally. A large quantity of solder adhering on the inclined plate pulls solder adhering on the leads sequentially along an inclined surface of the plate to obtain uniform thickness of solder plating on the leads without causing bridging.

Abstract: Disclosed is a method of manufacturing a high-yield solder bumped semiconductor wafer. The method comprises providing a non-solderable transfer substrate having a transfer surface for receipt of solder material; depositing solder material onto the transfer surface to form solder bumps in a predetermined pattern; aligning solderable conductive elements of a semiconductor wafer with the predetermined solder bumps on the transfer surface; and reflowing the patterned solder bumps into wetted contact with the wafer conductive elements.

Abstract: An improved thermite reaction containment vessel and method of using the same includes a crucible in which the exothermic material is contained and which is connected at its lower end via a tap hole to a weld chamber in which the parts to be welded are positioned. On top of the crucible is positioned a baffle assembly which includes a plurality of expansion chambers which allows the escaping gas to expand and be reduced in velocity. As the gases move from one expansion chamber to the next the gases change direction. The expansion, direction change and the large surface area of the baffle assembly allows the gases to slow and cool before being exhausted leaving behind molten metal spatter or flame and greatly reducing the amount of smoke exhausted since particulate matter is accumulated on the baffle interior surface. Several forms of baffle assembly are disclosed using inverted stacked metal cups.

Abstract: A controlled amount of flux is applied to a circuit board (10) by first directing liquid flux through a nozzle (54) containing means for disintegrating the flux into a very fine fog of tiny flux droplets (62). The fog of flux droplets is injected into a laminar gas stream (52), thereby creating a laminar flux stream which is directed at the circuit board to coat the board with flux. As the flux spray is being directed at the circuit board, the concentration of flux solids on the board is being regulated, typically by controlling the rate of flux pumped into the nozzle.

Abstract: A surface mounted chip soldering apparatus comprises a number of stations for fluxing and soldering the chip. For each station, the chip is carried by a suction pad in which is created a partial vacuum by a respective piston and cylinder mounted on a turret. The piston is upwardly spring biassed and operated in time and in sequence by pneumatically operated pistons to hold and to reject the chips as required for carrying out a soldering sequence.

Abstract: A controlled amount of flux is applied to a circuit board (10) by first directing liquid flux through a nozzle (54) containing means for disintegrating the flux into a very fine fog of tiny flux droplets (62). The fog of flux droplets is injected into a laminar gas stream (52), thereby creating a laminar flux stream which is directed at the circuit board to coat the board with flux. As the flux spray is being directed at the circuit board, the concentration of flux solids on the board is being regulated, typically by controlling the rate of flux pumped into the nozzle.

Abstract: A method of bonding semiconductor chips to a mounting surface and a nozzle for same includes the steps of applying a first deposit of a die attach adhesive material to the mounting surface in a manner wherein the first deposit has the general shape of a starfish. This starfish shape is characterized by a raised central portion disposed at the intersection of the radially inner ends of a plurality of centrally thickened arms. The next step is to apply the bonding surface of a semiconductor chip against the deposit to cause the deposit to spread therebeneath while removing air pockets and hence any voids within the die attach adhesive material. The volume of the deposit being proportional to the surface area of the bonding surface and the configuration of the first deposit being defined to cause uniform and symmetrical spreading of the first deposite across the bonding surface provides full coverage of the bonding surface with a uniformly thick layer of adhesive.

Abstract: Apparatus for performing an operation with molten solder, such as soldering or desoldering a component mounted on a substrate such as a PCB including an enclosed reservoir, the reservoir including a contained space above the molten solder; a hollow nozzle for receiving solder from the reservoir; an element for conveying the molten solder in the reservoir to the nozzle; and a source connected to the contained space for introducing a pressurized gas into the space to raise the solder through the conveying means to a predetermined level within the nozzle and maintaining said solder at said predetermined level to thus effect the operation with the molten solder and then removing the gas to return the solder to the reservoir. The gas is pulsed at least during the time the solder approaches and reaches the predetermined level. The apparatus includes a plurality of different size hollow nozzles for receiving solder from the reservoir where the nozzles are removably attachable with respect to the reservoir.

Abstract: A capillary for use in ball bonding tools designed to bond metal leads to the bonding pads on a microchip and pads or leads on a chip support is formed by chemically vapor depositing a substantially smooth silicon carbide coating having high electrical resistivity onto a substrate which is then removed by etching or combustion.

Abstract: An attachment device adapted to be fused to an underwater object which includes a housing having a fuel chamber in generally surrounding relationship to an ignition chamber, a closure normally closed in communication between the chambers, an ignition device which opens the closure and ignites the fuel in the fuel chamber creating a high temperature flame which is directed toward an end of the attachment device resting against an underwater object, the end having a fusion groove for directing the flame against a localized area of the underwater object to render the metal thereof molten, and also having one or more passages for redirecting the molten material back toward the attachment device such that upon solidification, one or more discrete rigidifying bridges of molten metal are formed, and a groove defined by a pair of lips is also positioned adjacent the end for further directing the high temperature medium to achieve effective fusion.