POLYCOR® 998 NEUTRAL BASE

POLYCOR® 998 Series Enamels should be mixed prior to use. Use mixing equipment with sufficient horsepower (relative to container size) to achieve thorough circulation from top to bottom and out to the sides of the container. The agitator must be properly sized for the container and must allow for uniform mixing regardless of the liquid level in the container. Mixing once a day for 10 minutes is typically sufficient. Air bubbling should not be used for mixing. It is not effective and only serves as a potential source of water or oil contamination.

Do not overmix POLYCOR® 998 Series Enamels. Overmixing can break down the coating viscosity increasing the tendency to sag. Overmixing can also result in styrene loss which could contribute to porosity. Air bubbling should not be used for mixing. It is not effective and only serves as a potential source of water or oil contamination.

Recommended application of enamels is by spraying, but they can be rolled. Brushing is not recommended due to poor flow and leveling. POLYCOR® 998 Series Enamels should be applied after the laminate has cured and while it still has a tacky surface. Glossy/resin rich laminates may cause the enamel to separate, sag, and have poor adhesion. Ensure that glossy areas are well sanded, then blow off the area and clean with solvent.

Laminates containing a wax surfaceor mold releaseshould be sanded before coating with POLYCOR® 998 Series Enamels. Sand with coarse sandpaper to remove all indications of wax or mold release, then wash with solvent.

If a fleck coat or cob webbing of POLYCOR® enamel is desired over the base coat of enamel, it should be applied while the base coat is wet.

Spray equipment must be well maintained and regularly calibrated. Application procedure recommendations should be followed carefully. Poorly maintained equipment or poor application will quickly negate the beneficial properties of POLYCOR® 998 Series Enamels. Refer to Polynt’s Composites Applications Guide, for equipment and application recommendations. Use the same equipment, settings, and techniques for spraying enamels as used for gel coats.

When establishing the fan pattern for the spray equipment, use the lowest pump pressure needed to achieve a good fan pattern (no fingers or tails, uniform particle size of about 1/16²). Use of higher pressures can lead to a porosity or excessive overspray.

Overspray can result in a leathery or chicken skin texture if it falls on the part surface. To minimize overspray that falls onto the mold, plan the spray pattern so that the beginning is closest to the vapor/air exhaust and progresses to the opposite mold end. The spray pattern should also allow for a wet line to be maintained.

A spray distance of 18 to 36 inches is recommended. Closer spray distances can result in blowing of the film or air entrapment. Spraying at distances greater than 4 feet will increase orange peel and porosity. For deep channels, recessed, and hard-to-spray areas, an extension nozzle is highly recommended.

Polynt Composites does not recommend fluid lines longer than 50 feet, or pumps smaller than 20:1 ratio. Polynt Composites recommends a gel coat delivery rate of no more than 2.5 pounds per minute with conventional air atomized equipment, and no more than 4 pounds per minute with airless equipment.

For optimum results, uniform catalyst mix must be achieved. Even with the equipment properly calibrated, potential problems can occur due to poorly atomized catalyst; surging problems (gel coat or catalyst); poor tip alignment (catalyst to gel coat mix); contamination; and poor application procedures, which will quickly negate all benefits of calibration. The equipment (and application procedures) must be monitored on a routine basis to ensure proper application and cure of the gel coat. Inquire about and adhere to all equipment manufacturers’ recommendations.

Avoid overspray settling on mold surfaces by beginning the spray pattern closest to the vapor/air exhaust and progressing to the opposite mold end. Maintain recommended spray distances from the mold surface.

For best overall performance properties, a wet film thickness of 18±2 mils is recommended as ideal. Films less than 12 mils may not cure properly, may be hard to patch, and are more susceptible to water blisters. Films above 24 mils may trap porosity or crack, and are more subject to weathering discoloration.

One gallon of POLYCOR® 998 Series Enamel will cover approximately 60 to 80 square feet, depending on the film thickness of the coating.