CAV-GRIP III Dos and Don'ts

CAV-GRIP^™ III Low-VOC Adhesive is an optimal choice when you’re installing fully adhered EPDM or TPO roofing systems. This low-odor adhesive requires minimal setup time, dries fast, and can be applied quickly and accurately. Plus, its long “open time” makes it a prime candidate for projects utilizing larger sheets.

Like anything else, there are dos and don’ts associated with using CAV-GRIP III. Check out these guidelines to ensure a proper, headache-free installation.

DO
Keep replacement tips handy – CAV-GRIP III spray guns have brass tips which achieve the optimal spray pattern. However, a clogged or damaged tip can negatively affect spray capabilities and result in wasted adhesive. To ensure that a damaged tip won’t delay your progress, it’s a good idea keep a bag of replacement tips handy.

Use a splitter – Consider using a splitter if you’re working with the larger 85 lb. cylinders. Splitters allow you to attach two hoses to one tank, which can double productivity.

Store properly – Store CAV-GRIP III cylinders in a protected, conditioned space with temperatures above 70°F prior to and during application. If CAV-GRIP is stored below the 70-degree mark, you’ll have to wait for it to warm up before application. If a cylinder is below the minimum temperature, it will produce an intermittent spray or “sputter” when it is used. TIP: try warming the product up before checking to see if your gun or hose are clogged.

Secure all cylinders – Make sure you properly secure cylinders (regardless of whether they’re full, partially full, or empty) so they can’t roll off the roof.

Use the right gun for the situation – The CAV-GRIP III Spray Gun with Extension Wand is perfect for wide-open roof areas, while the regular CAV-GRIP III Spray Gun (without the extension wand) is ideal for tight or confined areas.

Keep the gun moving – Keep the spray gun moving while you’re spraying the adhesive to avoid thick or puddled areas.

Adjust your technique if necessary – While you’re spraying, you may need to adjust the distance between the gun and the substrate to attain the proper coverage rate. In windy conditions, control the amount of trigger pull to ensure a proper web pattern is achieved and to prevent adhesive from being blown away.

Clean up – You can reuse your guns and hoses over and over again if you keep them clean. First, completely depressurize the cylinder. Disconnect the gun and hose assembly and immediately attach it to a canister of Low-VOC UN-TACK™. Pull the trigger and allow the UN-TACK to flow through the hose and gun for five to ten seconds, or until the liquid coming out is clear. Depressurize the UN-TACK, remove the assembly, and store for future use.

DON'T
Don’t wipe adhesive off the spray tip – Immediately after spraying CAV-GRIP III, you may see adhesive buildup on the tip of the spray gun. The installer’s first reaction is often to wipe away this residue with a rag; however, doing this forces cured adhesive back into the tip orifice, leading to improper spray patterns and ultimately a clogged gun. Instead, allow the adhesive to thicken on the tip and peel away the buildup when you’re ready to spray again.

Don’t shake – Unlike Carlisle’s Flexible FAST™ Dual Tank Adhesive, you do not need to shake the CAV-GRIP III cylinder prior to application. Shaking the cylinder will disrupt the adhesive and result in the loss of propellant, which is vital to achieving the expected 1,000 ft2 coverage rate per cylinder in a two-sided application.

Don’t tilt – Don’t tilt the cylinder or lay it on its side while applying adhesive. Doing so will result in air pockets within the gun and hose assembly which could affect the spray pattern and reduce your coverage rate.

Don’t mishandle – CAV-GRIP cylinders are pressured tanks and must be handled with care. Treat cylinders more like a propane torch set and less like a pail of standard bonding adhesive, both on and off the jobsite.

Don’t overspray – Don’t apply adhesive to splices to be hot-air welded or areas where primer and pressure-sensitive tape will be applied. If overspray occurs, use Weathered Membrane Cleaner or commercial-grade duct tape to remove it.

Don’t install membrane too soon – Don’t install membrane over wet or puddled CAV-GRIP III. Doing so will trap solvents between the membrane and substrate, causing “solvent bubbles”. Allow the adhesive about three to five minutes to set up, or become tacky, before installing membrane.

Don’t use band heaters in cold weather – Band heaters can reach temperatures of more than 400° F, which can cause over-pressurization inside the cylinder and lead to a valve failure and loss of product. Instead, try power-heated blankets and/or hot boxes when necessary.

Don’t let a disconnected hose sit around – Adhesive can cure inside the hose or gun, causing it to sputter or become blocked. When switching a hose and gun assembly from one cylinder to another, make sure both cylinders are sitting side-by-side during the change. Shut the empty tank off, point the wand into a trash bag, and pull the trigger to empty all excess adhesive out of the hose and gun. Then, unhook the hose from the empty tank and immediately hook it up to a new cylinder.

Don’t punch a hole through the side of the tank when the tank is under pressure – Once the hose is removed, open the tank back up slightly to relieve excess pressure. From there, punch a hole through the designated area and properly dispose of the tank.