Hot melt adhesive speeds precast form bonding
- Published: Friday, 22 April 2011 12:58
- Written by CP Staff
Suited for bonding reveal, chamfer, form liners, weld plates and structural and other architectural elements in all types of precast concrete forms, the new Power Adhesive hot melt system consists of Casttec adhesive, applied in dots, beads or a spray pattern using one of three heavy-duty TEC glue guns. Its replaces commonly used double-sided tape, solvent-based adhesives, bolting, nailing, silicon or other fastening systems; Casttec bonds to all material types common in the industry including wood, foam, most plastics and some metals.
A one-step process, the system does not require priming; secures a strong bond that sets almost instantly; and, offers what product developers contend is excellent form release for a fast clean up.
Casttec Precast Hot Melt Adhesive formulations impart strength to resist shear, preventing elements from moving on the form as the concrete is flowing and keeping critical form inserts from shifting. It remains tacky for up to three minutes in the event more precise positioning is required. Casttec re-crystallization occurs over an eight- to 10-hour period. The delayed process provides precast operators with maximum bond strength during the set-up and pour stage and makes the adhesive easier to clean off the form when elements are removed. The Casttec Adhesive is packaged as a 1-3/4-in. hot melt cartridge in 22 lb (10 kg) cartons. The adhesive is melted on demand as the pneumatic piston pushes glue cartridges through guns’ melt chamber and sprays it directly onto the precast form.
The 400-watt TEC 3200 Glue Gun is a high output, all-electric applicator with an auto-standby safety feature and up to 7.5 lb./hour melt rate. A solid-state, plug-in adjustable temperature controller and high efficiency heater housing apply the adhesive at temperatures of 265, 320 and 380 and 420°F. The 500-watt TEC 6100 is a self-contained, electric-pneumatic applicator that extrudes hot melt adhesive and requires only compressed air and electricity to operate. Melt rate is up to 9.25 lbs./hour, and the applicator reaches its maximum operating temperature of 380°F in 10 minutes. The 500-watt TEC 6300, reportedly the world’s highest output hand-held hot melt spray applicator, covers 21 sq. ft. with one cartridge, suits heat sensitive form materials, and has a 11.5-lb./hour melt rate.