Childers® Chil-Lastic™ CP-79 Sealant and Coating

• Chil-Lastic™ CP-79 Sealant and Coating exhibits good adhesion to most surfaces.
• It is acid and alkali resistant and will not freeze, decompose or show settling or separation in storage.
• Chil-Lastic™ CP-79 Sealant and Coating provides an excellent water and vapor seal.
• It forms a tough, protective coating when cured, which does not tend to crack or peel during normal equipment operation.
• Chil-Lastic™ CP-79 Sealant and Coating requires no special mixing or additives.

• Chil-Lastic™ CP-79 Sealant and Coating is used as flashing material in the sealing of boiler settings to prevent air infiltration. It is also used in refractory applications.

APPLICATION

• Chil-Lastic™ CP-79 Sealant and Coating is normally applied by trowel or heavy duty airless spray. See reverse side of product data sheet for spray recommendations.
• Chil-Lastic™ CP-79 Sealant and Coating trowel grade has a heavy body and can be applied in wet thicknesses up to 1/8” (0.31 cm) without sagging or running.
• CP-79-T or CP-79-S cannot be successfully applied by brush. CP-79-T cannot be spray applied.
• Failure to apply the full coverage specified can result in premature failure of the product. Do not under-apply CP-79.

Determining the Proper Viscosity

• It is necessary to determine the method of application based upon the overall size of the object being coated, since Chil-Lastic™ CP-79 Sealant and Coating is available in two viscosities (CP-79-T for trowel application and CP-79-S for spray application).
• Large, flat areas and/or objects that lend themselves to application by spray; CP-79-S is most appropriate for this type of situation.
• Smaller, irregularly shaped objects, such as fittings, lend themselves to application by trowel; CP-79-T is most appropriate for this type of situation.
• In addition, cost of spray equipment rental, purchase or use may be a factor in determining method of application.
• After the proper application has been determined, the proper product viscosity can be ordered.
• Do Not Thin.

Service Temperature Range

• For the temperature at the coated surface (the exposed surface), the service temperature range is -75°F to 350°F (-59°C to 177°C) if the temperature is continuous.
• Behind refractory, block or spray-applied, the temperatures at the refractory face can be 500°F (260°C) or higher, provided the temperatures behind the refractory (between the CP-79 and the steel shell) do not exceed -75°F to 350°F (-59°C to 177°C) if the temperature is continuous.

Application

• Prepare steel surfaces by abrasive grit blasting to remove all traces of mill scale, rust, paint and corrosion products.
• Remove all dust and grit from the surface.
• Apply the CP-79 promptly, before the blasted surface can flash rust.
• If absolutely necessary, the blasted surface may be primed with a thin coat of CP-79 cut 50/50 with mineral spirits.
• Apply the full thickness CP-79 application within 30 days.

Spray Application

• Chil-Lastic™ CP-79 Sealant and Coating is most readily applied by airless spraying equipment.
• Airless spray is faster, neater and gives a better, more uniform finish.
• A two-coat application will be required.
• Allow the first coat to set firm before applying the second coat.
• Industrial spray equipment is required to spray CP-79-S.
• It has a relatively high pseudoplastic consistency and a typical viscosity of 100,000 cps to 150,000 cps (Brookfield speed of 20 at 25°C).
• For this reason, it is necessary to have the spray unit mounted on an inductor plate (also called a ram plate) which will keep feed pressure on the mastic to the pump and avoid cavitation.
• For best results, consult a qualified industrial spray equipment dealer for equipment recommendations. 

• Most manufacturers of mastic spray equipment maintain nearby service facilities to aid in the solution of any technical problems that arise with their equipment.