PAINTS

TM 43-0139 (3) Application. Apply by hot spray as issued; by cold spray, thin with three parts by volume of thinner to five parts by volume of lacquer. Use the manufacturer's recommended thinner. d. Lacquer, Aircraft (MIL-L-46159). (1) Characteristics. This is a single-color (Aircraft Green), low reflective, single-component, lead and chromate free lacquer. (2) Use. Use as a two-coat finish for the exterior surfaces of Army aircraft. It can be used in a wide variety of temperatures (40°F to 90°F (4°C to 320C)) and humidities (15 percent to 70 percent). Excessively high temperature with low humidity can result in dry spray, however, and excessively high temperature with high humidity can result in blushing. Apply over primer MIL-P-23377 or TT-P-1757. (3) Application. Apply by spray when thinned with up to one and one-half parts by volume of thinner, MILT- 19544, to one part by volume of MIL-L-46159. Mix only the amount necessary for use that day. MIL-L-46159 must be thoroughly mixed in its container prior to adding thinner. Constant agitation is also required throughout the painting process. Test on another surface prior to painting aircraft to ensure proper spray viscosity. If excessively high temperatures and/or humidity are encountered, the lacquer/thinner mixture may be combined with up to 30 percent by volume of acrylic lacquer retarder, MIL-E-7125. Apply two coats of mixture to a dry film thickness of 1.5 mils. WARNING Use impervious, not cloth, gloves when mixing any component containing MIL-E- 7125. (4) Drying Time. The first coat will air dry in 30 minutes. Lightly wipe prior to applying second coat. The second coat will dry to touch in 30 minutes and is ready for flight in four hours. 2-34. PAINTS a. General. Paints are mechanical mixtures or dispersions of pigments in a nonvolatile liquid. A volatile solvent or thinner is used to reduce the paint to the proper consistency for application. The pigmented liquid, after application to the surface by brushing, spraying, or dipping, dries to form a solid and opaque coating. An oil paint contains a drying oil or oil varnish as the basic ingredient. A paste paint is one that permits a substantial addition to the vehicle of thinner to obtain the consistency required for application. An asphalt paint contains asphaltum or a similar substance as the principal nonvolatile ingredient; this also provides the coloration of black or brown. b. Paint, Acid-Proof, Black (MIL-C450). (1) Characteristics. This paint consists of a material of petroleum or asphalt (bitumen) or a combination of both, thinned with aromatic petroleum naphtha or mineral spirits paint thinner, TT-T-291, to the required nonvolatile content. It contains no drying oils resins, or pigments. This paint is highly resistant to acids. (2) Use. It is used on metal or wood battery boxes and their supports, and also in the assembly of certain ammunition items. c. Coating, Underbody (FT-C520). (1) Characteristics. This compound is a mixture of asphalts, fillers, solvents, and additives processed to meet specified requirements. (2) Use. Use as a protective underbody coating for automotive equipment and as a sound deadener. 2-16