It used to be so simple-screws or glues? When it was time to attach all the different parts of a widget, the designer had only two choices. And the battle lines were clear-if you had to space two parts, use bolts and washers. If you needed to transfer heat, use metal fasteners. If you needed a lightweight assembly, use a glue.
But today's adhesives manufacturers are muddying these waters by offering glues that can do many of the jobs once reserved for screws, sewing, cements, and other options. From Loctite Corp., a new thermally conductive epoxy potting compound called LoctiteŽ3861 has the low viscosity and chemical resistance for applications in electronic casting and encapsulating jobs. The heat-curable material has low thermal expansion, high wetting and flow capabilities, strong thermal shock resistance, high heat transfer abilities, and even strong electrical properties. It cures in two hours at 100C, or one hour at 180C, to produce a bond that is resistant to weather, water, gases and vapors, petroleum lubricants, and many acids and alkalis, so it can be used even in harsh environments like automotive applications.
ABLEBOND 9349K is a gray, two-part epoxy that is manufactured with glass bead spacers to control the bond line thickness. With a lap sheer strength of 2,100 psi, it forms strong bonds with many metals and woods, plastics, rubbers, and masonry, says Tra-Con Inc.
Also from Tra-Con, TRA-SEAM 5001 is a clear, medium-viscosity acrylic adhesive that is formulated to be non- discoloring, for applications such as a seam fill for bathroom tile finishes and other solid surfaces. It is room-temperature curable, can be adjusted to cure in a variety of different colors, and will bond to acrylics, polyester, butyrate, PVC and styrene.
For a heat-activated, pressure-sensitive adhesive (PSA), Adhesives Research Inc. makes ArcladŽ7353 to replace seaming and sewing applications during manufacture of textiles such as fiberglass, automotive fabrics, carpets, and other specialty woven and non-woven materials. It is a flexible PSA designed to move quickly over accumulators and tension bars, so it will hold through rigorous manufacturing processes such as tufting, dyeing, water baths, and extreme heat.
Constructed of cast aluminum (Al Si 12), and designed for high impact and extreme temperature applications, the AL Series includes 16 enclosures ranging in size from 50 X 45 X 30 to 330 X 230 X 110 mm. The base and cover are connected with pre-mounted stainless-steel cover screws compatible with Phillips and straight-edge screwdrivers. The AL Series features IP65 protection, resistance to chemicals and damaging materials, and electromagnetic interference.
Altech Corp., 35 Royal Rd., Flemington, NJ 08822-6000; FAX (908) 806-9490; www.altechcorp.com.
Scapa 705 is a clear, pressure-sensitive adhesive film, double coated with custom formulated silicone and acrylic adhesives. It is designed to bond well to difficult materials like gaskets, foams, and sponges, but its high-tack qualities also allow it to bond to substrates like glass, plastics, and metals. 705 can serve as a splicing tape, to join silicone-coated papers or films, and is also ideal for high- or low-temperature gasket sealing, precision die cutting, forming to intricate parts, and general purpose bonding.
Scapa Tapes, 111 Great Pond Dr., Windsor, CT 06095; FAX (860) 688-7000; www.
SPEEDBONDERadhesives are formulated to provide tough, durable bonds to a variety of surfaces including metals, plastics, and composites. The new two-part products are available in two categories: toughened for applications requiring the most durable bond strengths; and low odor/non-flammable to meet the strict health and safety requirements of today's work environment. Capable of filling up to 2-inch gaps, these adhesives cure at room temperature to offer high shear strength, excellent flexibility, and toughness without sagging; and they will withstand temperatures up to 250F.
Loctite, 1001 Trout Brook Crossing, Rocky Hill, CT 06067; FAX (860) 571-5465; www.locite.com.
TRA-BOND 2143D is a medium viscosity, room-temperature curable, polyamide adhesive formulated to be chemically resistant to many materials and tough under impact. Reportedly, foreign factors such as weather, water, salt solutions, most petroleum products, mild acids and alkalis, among others, do not harm the integrity of 2143D. The adhesive is also available in a TRA-PAK, a dual-barreled cartridge with a static mixer attached to its tip for easy mixing and application.
Tra-Con Inc., 45 Wiggins Ave., Bedford, MA 01730; FAX (781) 275-9249; www.tra-con.com.
HanŽEss industrial connectors offer a matchable and reliable electrical transmission of signals and power, according to the company. By means of two cage clamp terminations per contact it is possible to multiply signals, bridges, T-connections or lead-through of network signals, and power under industrial conditions. A simple screwdriver is sufficient to connect and disconnect wires. Typical applications include bus systems, branch connections, distribution, and matchability of motors.
Harting of North America, 1370 Bowes Rd., Elgin, IL 60123-5538; FAX (847) 741-8257; www.harting-usa.com.
Known as the MA 1000 Series, these new adhesives have low shrinkage and are ideal for structural bonding of "green" composites, thin wall thermoplastics, and thin metals where other adhesives or assembly methods show read-through of the bondlines. The two-part adhesives require virtually no surface preparations, are low odor, and have long-term durability. Working and curing times vary within the series to match applications.
ITW Plexus, 30 Endicott St., Danvers, MA 01923; FAX (978) 774-0516; www.itwplexus.com.