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 (2) Application Thickness. Unless otherwise specified, apply each coat of paint to produce
approximately three mils dry film thickness (DFT). Coating applications in excess of 4.0 mils DFT should
be avoided. Brush Application. During maintenance painting, brush application is recommended for the
first coat of paint over mechanically cleaned surfaces and hand-cleaned bilges. The brushing effort forces
the paint into the surface profile and displaces any traces of surface contaminants
(3) Tack Coat for Topcoat Paints. If more than 7 days elapse between preservation coats of the
epoxy, the surface should be cleaned with water, detergent, and rinsed clean with freshwater. If required,
use solvents for grease and oil removal. Then a tack coat (1 to 2 mils WFT) of the last coat applied is
applied to the hard epoxy coat. It is allowed to dry approximately 4 hours before application of the next full
wet coat of the system. This same procedure applies to aged epoxy paint systems after service, except
that surface preparation methods specified in paragraphs 3-4.a.and 3-4.b apply. Epoxy primer should be
used as the tack coat when applying epoxy paints over proprietary epoxy coatings.
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(4) Equipment Cleanup. Since epoxy paints cure with time, due to an internal chemical reaction, the
paint should not be allowed to remain in spray equipment for an extended period, especially in the sun or
in a warm area. Paint cures more rapidly at higher temperatures. When components A and B are mixed
together, the pot life of the mixture (including the induction time) is 6 hours at 21.1C (70F). Pot life is
longer at lower temperatures and shorter at temperatures above 21.1C (70F). After use, spray
equipment should be cleaned by flushing and washing with EGM ether solvent. General cleanup is also
done by using EGM ether solvent. Brushes and rollers should be given a final cleaning in warm soapy
water, rinsed clean with warm freshwater, and hung to dry.
application of vinyl paints are described below. Refer to section 2 for a more detailed listing of
precautions.
a. Safety Precautions:
(1) The solvents used in the vinyl systems component formulations are more flammable than the
solvents in most other shipboard paints. The vapors can produce physiological and toxic effects if
breathed continuously for long periods. All precautions and safety measures pertaining to flammable
materials such as no smoking, welding, burning in the immediate areas, grounding of spray equipment,
and elimination of chipping and other spark producing operations shall be enforced. Respirators for spray
painters and explosion-proof ventilation shall be used.
b. Surface Preparation. A clean dry surface, free of contaminants, is especially critical in the
application of vinyl paints improper surface preparation will result in unsatisfactory paint performance.
(1) Prior to the application of vinyl paints, the removal of scale, corrosion, dirt, grease, oil, marine
fouling, and other foreign matter from the surface shall be completed. The method of cleaning depends
upon the amount and the type of cleaning required. For metal surfaces, abrasive blasting is the most
effective method for surface preparation. A solvent wash and light blasting or mechanical roughening may
be used to rid new-galvanized steel of fatty material and flux components, as well as to provide a suitable
anchor pattern. This is required for satisfactory adhesion of pretreatment primer.
(2) Cleanup. During cleaning operations, considerable dust or debris will collect on otherwise clean
surfaces. Depending upon weather conditions, some rusting may occur. Any contaminants on the surface
to be painted must be removed prior to coating application.
(3) Touchup Surface Preparation.
(a) For vinyl bottom paint touchup, surfaces shall be washed down with streams of high-pressure
water after docking to remove mud, slime, scum, and loose marine fouling. Light blasting may be used for
removing adherent marine life from intact paint. Prior to touchup, deteriorated areas of old paint and
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