Wire tacking

Cyanoacrylate adhesives (Super-Glues) are materials which rapidly polymerize at room temperature. The standard monomer for a cyanoacrylate adhesive is ethyl 2-cyanoacrylate [7085-85-0], which readily undergoes anionic polymerization. Very rapid cure of these materials has made them widely used in the electronics industry for speaker magnet mounting, as weU as for wire tacking and other apphcations requiring rapid assembly. Anionic polymerization of a cyanoacrylate adhesive is normally initiated by water. Therefore, atmospheric humidity or the surface moisture content must be at a certain level for polymerization to take place. These adhesives are not cross-linked as are the surface-activated acryhcs. Rather, the cyanoacrylate material is a thermoplastic, and thus, the adhesives typically have poor temperature resistance. 

Examples of some of the current uses for these adhesives include retention of automotive gaskets, weather stripping, side trim, and wiring harnesses athletic shoes swim masks shotgun recoil pads arrow feathers dolls and doll furniture circuit board component mounting and wire tacking and lipstick tube and compact mirrors. Aledical devices include balloon catheters and tubing sets the adhesives are used by morticians to seal eyes and lips. 

Chip bonding Speaker software assembly Wire tacking Temporary bonding Ferrite magnet assembly Electrical leads to lamp housing... 

Dymax Light Weld 931/ urethane acrylate 0.5 2,053/N/A UV light 5 sec Coil termination and wire tacking... 

A common method of wire-tacking today is to use cyanoacrylate adhesive and primer. In this process, a drop of cyanoacrylate is placed on top of the wire to be tacked, followed by a drop of primer. The resulting wire-tack is usually serviceable in 5 - 15 seconds although several hours can be required for full cure. The usage of the wire tack, although limited by a lack of moisture, temperature and impact resistance, has been finding increasing application in the electrical industry. 

UV-curing aerobic acrylic adhesives, while less expensive on a per pound basis than cyanoacrylates, provide a structural wire-tack that resists environmental conditions. A useful property is that the aerobic acrylics fluoresce to optimum brightness only upon completion of cure, providing a visual means of end-point determination. An elastomer formulation is recommended for permanent wire-tacking in a high vibration environment. Removable wire-tacking formulations are also available (Fig. 1). 

Wire tacking Instrument assembly Fiber optics adhesives Speaker assembly... 

Lamp assembly Electrical leads assembly wire tacking... 

Seconds to Cure Seconds to Cure Approximate (2 mil gap between (1/8 inch deep Price Range glass slides) wire tack)... 

Calculators Coil binding Computer assembly Electronic parts Hearing aids Microprocessors Medical equipment Small electric motors Speaker magnets Stereo components Wire tacking... 

Wire-tacking adhesives - cyanoacrylates and UV acrylic adhesives can be used to tack wires in place. Cyanoacrylates are applied to components and then a topical activator is applied by brush or spray to cure the adhesive instantly. UV adhesives achieve the same result and give more heat-resistant bonds. 

Wire tacking, which is the temporary or permanent rapid immobilization of wires at specific locations by touching them to an adhesive drop in the desired location, is a relatively recent innovation in the use of adhesives. The technique, which is widely used with printed circuit boards and other fine wire applications, depends upon fast curing adhesives which develop adequate joint strength in a matter of seconds. Since heat is not required to cure the bond, the technique is ideal for... 

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