Sprayer Equipment Guidelines for W. R. MEADOWS Fluid-Applied Membranes

Recommended Spraying Equipment

Extensive field testing has shown that the Graco GH 833 Big Rig or Hydra Max 350 (now obsolete) sprayers work best for spraying of the water-based AIR-SHIELD_™ LM, AIR-SHIELD LMP, AIR-SHIELD LSR, AIR-SHIELD TMP, and MEL-ROL_® LM products. We are not aware of any other types of sprayers being used successfully with our products. Initially, we had used the Gmax 7900 Roof Rig, but we have found that the pressures (4000 psi) attained by the Graco GH 833 Big Rig and Hydra Max 350 units yield more consistent, trouble-free results. The Graco GH 833 Big Rig and Hydra Max 350 units are capable of a 3.5 – 4.0 gal./min. output, compared to a 2.1 gal./min. for the Gmax 7900 Roof Rig. The water-based emulsion products are extremely shear sensitive and should NOT be applied through gear-type pumps or pressurized follower plate systems. These systems will cause the emulsions to break, which will then clog the equipment.

The Graco GH 833 Big Rig unit comes equipped with 100′ of hose, a texture spray gun, and several tips. NOTE: The standpipe on the sprayer MUST be opened and checked for the presence of a filter element and plastic sleeve. For AIR-SHIELD LM and MEL-ROL LM, these MUST BOTH be removed prior to use, as they will cause clogging.

Both the Graco GH 833 Big Rig and Hydra Max 350 can be used for five-gal. pails or 55-gal. drums. Extensions on the pumps are able to create enough suction to allow material to be pulled from the top of a standing drum (or tote) of product. (An option available for the Graco GH 833 Big Rig allows the pump to be placed directly over a drum for improved pumping of thicker materials in cooler weather.)

Equipment

Hose

We have used up to 100′ of hose with these products. (Longer lengths may work; possibly up to 150′.) The hose must be rated for use up to 4000 psi for these units. W. R. MEADOWS recommends using separate hoses specific to each material.

Spray Gun

The Graco heavy duty texture gun is required (part #241705). It does not contain a paint filter and works well for these products. Other Graco guns have not worked, as they contain a diverter pin in the spray nozzle that will constantly clog the gun.

Spray Tips

We have used the 0.051″ (Graco 551,651) tip successfully for spraying and this is our preferred tip size for MEL-ROL LM/AIR-SHIELD LM products. For spraying of AIR-SHIELD LMP, AIR-SHIELD TMP, and AIR-SHIELD LSR, the 0.051″ tip will work, but using the 0.035″ or 0.037″ tip will yield a smoother finish on the wall.

NOTE: Tips should be the “reversible” type for easy clean out.

Recommended Equipment for Co-Spray Dispense of
AIR-SHIELD LM, CURE-IT, and MEADOW-PRUF CO-SPRAY

Co-Spray Spray Package by CJ Spray Inc. — Minneapolis / St. Paul, Minnesota
(www.cjspray.com)

 

The GH-833 Airless Spray Pump, manufactured by Graco, dispenses the AIR-SHIELD LM and MEADOW-PRUF CO-SPRAY. The co-spray Electric Pump by CJ SPRAY dispenses the CURE-IT. The Co-Spray assembly can be attached to conventional one-part pumps. The Graco GH 833 has been verified as suitable for dispensing AIR-SHIELD LM and MEADOW-PRUF CO-SPRAY utilizing the CURE-IT Co-Spray technology.

Co-Spray Pump Assembly

• GRACO GH-833 AIRLESS SPRAY PUMP
• HOSE KIT, CO-SPRAY, 50 FT, 3/8 X 5/16; 50′ 3/8 HOSE, 50′ CO-SPRAY HOSE (CJ SPRAY Part Number S10448-50)
• CO-SPRAY GUN, WHIP HOSE KIT (CJ SPRAY Part Number S10448-55)
• CO-SPRAY GUN, SILVER PLUS; SPECIFY XHD TIP AND CO SPRAY TIP Size (CJ SPRAY Part Number SB246240)
• GUARD RAC XHD (GRACO Part Number XHD001)
• 110V ELECTRIC PUMP W/ BYPASS (CJ SPRAY Part Number T10622-01)
• Spray Tip for AIR-SHIELD LM and MEADOW-PRUF CO-SPRAY: Graco XHD 551
• Spray Tip for CURE-IT Solution: Spraying Systems Co. H1/8VV-316SS9501

Co-Spray Application

Back out pressure dial on Graco pump to lowest setting. Start-up engine on Graco pump according to manufacturer’s instructions. Make sure Graco pump is loading by running AIR-SHIELD LM and MEADOW-PRUF CO-SPRAY through purge line. To do this, open purge valve and raise pressure on Graco pump to the lowest setting that will move material through the purge line.

DO NOT OPEN the purge valve if the pump is pressurized – discharge the pressure through the spray gun, pointed in a safe direction, then open purge valve. Collect material discharged through purge line in a container. Re-use purge material or dispose of in accordance with local, state and federal regulations.

Shut off purge valve once piston on Graco pump is observed to cycle smoothly up and down. Turn on Co-Spray, the pressure will be preset. Pull trigger CO-Spray Gun to commence spraying. Ensure that the spray pattern is even having no runs, fingers or heavy stripes at the edge of the spray pattern.

If spray pattern is uneven, raise pressure or reduce nozzle size to even out spray pattern. Spray must fan out evenly on AIR-SHIELD LM, MEADOW-PRUF CO-SPRAY and CURE-IT nozzle. Clean dirty nozzles or replace worn nozzles as necessary.

Spray Technique

Operator shall spray with the nozzles positioned 20 to 24 inches from the surface. Spray lower area first, working upward. Keep spray direction square with wall surface.

Hot Weather Application

CO-SPRAY application in hot weather and in direct sun will result in blistering of the membrane. To avoid blistering, wait until cooler time of day and not in direct sun to apply the AIR-SHIELD LM and MEADOW-PRUF CO-SPRAY or switch over to 1-Part spray installation.

Cold Weather Requirements

For spray installation in winter conditions, spray rig and products must be kept in a heated area maintained between 50°F and 80°F. Keep line and gun inside of heated space unless product is moving through lines in spray application. In-line heaters can be used, but these should not heat the material warmer than 120°F. Warmer material sprays and cures better than colder material. Minimum required material temperature is 50°F for effective spray application.

Application – Primer

Priming

Priming of poured concrete substrates may be required to minimize the potential for blistering of the membrane after it is applied and when exposed to direct sunlight. Once applied, the primer coat should be allowed to dry and be allowed to “warm up” while exposed to direct sunlight. Allowing the primer to be exposed to direct sunlight prior to the membrane application will allow the surface to “warm up” (due to the black color) and help “de-gas” the surface. This “degassing” releases the air/moisture vapors in the pores of the substrate, allowing them to expand and dissipate prior to the membrane application. If the primer is not exposed to direct sunlight for a sufficient time interval prior to membrane application, then blistering of the membrane may occur.

Primer Dilution / Application

RATE: Dilute the water-based LM products 4–5 parts product to one part water. Apply at 100–150 ft.²/gal. and allow to dry approximately one hour. AIR-SHIELD LMP, AIR-SHIELD LSR, and AIR-SHIELD TMP typically do not require a prime coat.

Application – Membrane

Spray

Several coats may be required to obtain the recommended thickness without excessive running or slumping of the wet membrane in hot weather. Allow the first coat to dry approximately one hour before application of the second coat.

NOTE: MEL-ROL LM and AIR-SHIELD LM can be sprayed easily when the material temperature is 40°F or above. The material temperature of AIR-SHIELD LMP, AIR-SHIELD LSR, and AIR-SHIELD TMP should be 40°F or above to be successfully sprayed.

Filter is recommended for use in applications of AIR-SHIELD LMP, AIR-SHIELD LSR, and AIR-SHIELD TMP.

Roller

Material can be roller applied if a ¾″ minimum nap roller is used. Several coats will typically be required to obtain the desired thickness. Allow the first coat to dry thoroughly before second coat is applied. Foam-type rollers or shorter naps should not be used, as they will simply slide on the substrate.

Rinse and store all rollers used for water-based products in a container of water when not in use. This is necessary, as the material will cure very quickly on the rollers if allowed to “dry out.” If this does occur, the rollers will need to be discarded or cleaned with solvent and allowed to dry thoroughly prior to reuse.

Equipment Cleanup

Water-Based Products

• Solvents must NOT come in contact with the liquid emulsion AIR-SHIELD LM and MEL-ROL LM products while in the sprayer, as they will immediately break the emulsion and plug up the entire sprayer system.
• Before starting to spray, the sprayer MUST be flushed with clean water.
• When spraying is complete, material must NOT be left in the pump, lines, or gun, as the MEL-ROL/AIR-SHIELD emulsions will quickly begin to break and cure in the equipment. When finished spraying, WATER ONLY should be PROMPTLY flushed through the system until pump and hose run clear.
• Do NOT add soap to the flush water, as it too will break the emulsion. “Simple Green” cleaner is the only cleaner found that can be used successfully.
• Solvents, including xylene, toluene, mineral spirits, paint thinner, gasoline, etc., must NOT be used for the initial flushing of the system. These solvents will break the emulsion and clog the system.
• Flush CURE-IT electric pump and spray lines with clean potable water until all CURE-IT Solution has been flushed. Do not use solvents.
• Aromatic solvents (xylene or toluene) are recommended for the final flushing AFTER water has been flushed through the pump and lines.
• If solvent is pumped through the system after being flushed with water, all equipment MUST be flushed with water before spraying emulsion. All traces of solvent MUST be completely removed.
• Aromatic solvent may be used to soak and clean the pump housing, gun, and tips.
• Solvents can be left in the sprayer for short durations (days) to aid in cleaning of the system. Solvents left in the sprayer for extended periods may begin to degrade the seals and hose.
• Again, all traces of solvent MUST be removed prior to using the equipment with the water-based emulsion products.

2025-06