All materials should be conditioned at room temperature prior to fabrication. Surfaces should be dry, clean, and grease and dust free. Hold the gun parallel to the work surface applying an even flat coat of adhesive. The adhesive should create a webbing affect across the substrate covering 80 - 100%. The spray gun is adjustable by opening the wheel located behind the trigger. The wider the spray pattern being applied the further away the gun nozzle should be held. Do not allow the adhesive to puddle or concentrate in one area.
It is important to remember that Grabfast is a contact adhesive and forms its bond by adhering to itself so there must be sufficient adhesive on both surfaces. The substrates are ready to be brought together after the solvent has flashed off, this can be determined by the adhesive being dry to touch with no transference to the finger (approx. 30-60 seconds).
Applying a second coat over both substrates will dramatically increase the strength of the bond, but the second coat should only be applied after the first has dried. Once the second coat has cured (the whole operation only takes minutes) the substrates can then be brought together, ideally using a J-Roller, applying uniform pressure (70lb per linear inch is recommended). It is important that when Grabfast is double-coated the two surfaces are brought together within one hour to achieve maximum performance.
As this revolutionary system requires two coats for ultimate performance it is important to apply two thin coats: therefore, a clean spray tip is essential. The brass spray tips can be cleaned by submerging them in solvent (methylated spirits or equivalent). Useful tip: Always keep a spare tip, one in use and one cleaning. Additional brass tips are available from Gemini Adhesives.
Connect the gun to the canister using the hose and ensure all connections are tight. Finger tight is not secure enough. Hold the gun parallel to the work surface and apply a generous coat. Wait for the adhesive to tack up i.e. to be dry to the touch without any transference to the fingers.
It is important to remember that Grabfast is a contact adhesive and forms its bond by sticking to itself. Hence there must be enough adhesive on both substrates to allow this to happen. Coverage of 80 to 100% is recommended. If it is possible and practical, the ideal procedure is to spray one surface vertically and the other horizontally.
On porous surfaces and edge banding a double coat of adhesive is advised. Ensure the first coat has dried before applying the second. Grabfast should not be allowed to puddle or concentrate in any one area. Grabfast is a pressure-sensitive adhesive so uniform pressure of 50-70lbs should be applied after the two surfaces have been brought together. A hand held pressure roller is ideal for obtaining the strongest bond. Ideally all substrates to be bonded should be preconditioned prior to use. They should be clean, dry, and grease and dust free.
Laminates especially should be stored at approximately 20°C with relative humidity of 45-55% for 48 hours before bonding. Air should be allowed to flow freely around the components. Grabfast dries in 2 minutes under normal conditions. High humidity and low temperature will slow the drying time. If the temperature gets too low bloom can occur. This is where moisture forms on the glue line and blisters may start to appear over time. Never bring the two surfaces together prematurely as solvent will be trapped causing bubbles. Although the adhesive bonds a wide range of substrates please test in an inconspicuous area first.
Troubleshooting:
Never turn the canister off until ready to connect a new canister; turning it off prematurely could result in the hose and gun becoming blocked.
If the gun will not spray:
Check valve turned on at the canister
Make sure gun wheel turned on
Spray tip clear of any congealed adhesive
Is there a blockage in the hose?