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Question

Could you explain the proper way to mix waterborne CARC for HVLP application?

Answer

64159 WD-CARC is furnished in two components: Component A and Component B. Component A consists of prime and extender pigments, additives, and solvents. Component B consists of an aliphatic isocyanate prepolymer type that is dispersible in water.

The mixing ratio is two parts component A to one part component B. Make sure that component A or B does not come into contact with water or extended exposure to high humidity before mixing. It's a good practice to always place the lid back on paint containers immediately after use. Leaving the lid off of the paint container for an extended period of time before mixing allows moisture and foreign materials in the surrounding area to contaminate the components. If this occurs material may slowly undergo chemical changes which may result in components not being useable.

Component A should be shaken for 5-10 minutes on a paint shaker, and then one part, by volume of component B is carefully poured into two parts, by volume, of component A. Use a high-shear conical mixer to vigorously agitate the combined components for at least three minutes. An air drill capable of 2000 rpm is necessary to create sufficient shear to incorporate materials.

The mixture of component A and B results in a high viscosity material that would be difficult to spray with HVLP spray equipment. In order to reduce the viscosity of the material so that it's sprayable, a percentage of deionized water is added to the mixture. When adding the deionized water slowly pour into the vortex created by the conical mixer for at least one minute or until uniformly mixed. See chart below for appropriate mix ratio based on color.

Mix Ratio Based on Color

Color	Number	Mix Ratio
Aircraft Green 34031	F93G503	2 : 1 : 0.5
Green 383,34092	F93G501	2 : 1 : 0.5
Black, 37030	F93B504	2 : 1 : 0.5
Tan 686A, 33446	F93H503	2 : 1 : 0.5
Brown 383, 30051	F93N504	2 : 1 : 0.5

Ratio = Component A : Component B Deionized Water
Finally, before the material is sprayed, it is important to use a viscosity cup to identify if the material is within the manufacturer's specified viscosity range. The manufacturer's viscosity range can be found on the product data sheet. If you would like a copy of the product data sheet for 64159 water dispersible CARC call (319) 277-4668 and ask for Jeremiah.

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