Instructions for applying boat
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1. Setting up to paint your boat bottom
You can paint your hull safely and easily when on your trailer, cradle, or
blocked storage system. Support points should be
touched-in just before launching. Just shift the boat, sand lightly, touch-in, and wait 10 to 30
minutes before launching. Our copper nonstick and our clear
nonstick paints dry in 10 minutes or less. Our urethane nonstick paints
dry in 30 minutes.
2. Pressure washing your boat bottom
The key to bottom painting is adhesion. To allow your bottom paint to
adhere well, your bottom surface must be hard, clean, and have a slight
texture. A once-over with a 3500 psi pressure washer or better is the
first step. If the existing paint is soft, where your fingernail can dig
into it, you will need to bring it down to a hard finish. Using a
spiraling tip on your pressure washer that applies a round stream will
give you the most pressure at the hull surface. These spiraling tips can
peal off soft oblate finishes to a surface that will not scratch with your
fingernail. When you get there, you can quickly sand the bottom.
3. Prepping your boat for bottom paint
Sanding your boat bottom with an 80- to 100-grit sponge or palm sander is
a quick and easy way to remove remaining contaminants and wax, while
leaving a microscopic texture for your new boat bottom paint to adhere to.
Dry sanding works well but sometimes tends to clog the grit surface
requiring changes of sanding paper or sponges. Wet sanding often keeps
sanding paper or sponges open to continue their work. Use whichever method
is easiest. While sanding, extra time can help smooth out gel coat
repairs, burs, and scratches.
4. Repairing irregularities in your bottom
You may use glazing compound over your old paint or between new coats to
fill and smooth the hull before applying your new boat bottom paint. You
should lightly sand, and wipe dust free, any surface before coating.
Touching in or striping newly glazed areas is recommended before the final
coat is applied. This will help prevent show through, by (in effect)
adding an extra coat over the repaired areas.
5. Taping your waterline or striping
Using a fresh role of blue masking tape will save a lot of time and
effort. Once the hull is dry, you can pull the tape from stem to stern.
Use a chalk line if you wish or follow your old water line. To stripe, you
can use striping tape or just pull two tapes along your hull and brush
your color in from the tap to the center. Whenever you use tape, it is
best to pull it off before the bottom paint dries or you may glue it to
the hull. Have a little thinner available before the bottom paint dries to
6. Mixing bottom paint
- The clear nonstick boat bottom paint is
ready to use but should be stirred. It will not
yellow over time. The clear can go over any surface without changing the
underlying color. Most boat waxes are water based and will wash off with
time as they dissolve in water. Smooth Sailing clear nonstick can be used
both below and above water to protect boat hulls in place of on going
- The copper nonstick boat bottom paint comes with the copper component
in a separate pouch. This is to prevent the copper grains from settling in
the can before application. You need to add the copper powder into the
clear nonstick coating and stir until fully mixed (about 1 minute) before
application. The copper will stay suspended for about 24 hours but mixing
occasionally is a good idea.
- Smooth Sailing urethane nonstick coating
is a two-part mix. The catalyst is mixed with the color component at a 3
to 1 ratio by volume. Once mixed, the coating should be applied within 2
hours, as it will set up in the can within 18 hours.
7. Clear and copper coating characteristics
The nonstick clear and copper have almost no odor and dry in 10 minutes or
less on the hull. The boat can be placed in the water immediately so areas
that had pads or rollers can be coated as the boat is moved to the water.
8. Characteristics of nonstick urethane
Smooth Sailing urethane comes in popular colors and lasts up to 11 years
without recoating. While our urethane contains no copper as a deterrent to
organisms, it does have an antifouling agent and a very low drag
coefficient so most organisms slide off at speeds of 15 to 20 knots.
Urethane does have some odor. When applying in closed spaces, a vapor mask
is recommended. In open air, no mask is normally required. The product
starts to dry in about 10 minutes and is hard enough for launching in
about 30 minutes in warm weather. Application should be done in
temperatures of 55 degrees F or higher.
9. Application of coating
The first coat should be sprayed or applied with a 9-inch mohair roller and/or brush.
The second coat can go on any time after the first coat is hard, but
waiting about 15 minutes for the copper and clear and about one hour for
the urethanes is recommended. Avoid introducing air into the urethane to
avoid bubbles. If bubbles occur some light sanding may be needed and a
recoat of the bubbled area.
10. Tricks for application
Putting your mixed boat bottom paint into a squeeze bottle, such as a
clean dish soap bottle or a squirt type drinking bottle, can help keep the
solvents used from evaporating. The less air exposure your mixed paint has
the easier it will flow over the boat bottom surface. Going just one
direction during your application helps to avoid bubbles. Starting low and
moving up helps limit drips. Using a threaded handle on your roller frame
allows you to reach center areas without getting dripped on. Taping your
brush to a long handle with duct tape helps reach spots that your trailer
or cradle tends to keep you from.
11. If you want to strip off your old finish
Often just pressure washing with the full force of at least a 3500 psi
washer with a spiral tip that can apply a round stream will remove some
boat bottom paints and contaminants. If you wish to remove the entire
finish, you may sand to the starting finish material. You can often
chemically remove your bottom paint by applying a methylene chloride type
of paint stripper. (Durall makes a good one.) Chemical stripping requires
plenty of ventilation, and a VOC vapor mask should be used. Often, using a
4-inch, long-handled scraper as you do your cleaning prep or paint
stripping can remove all the previous finish that is about to come off the
hull. Finishing with a degreaser and pressure washer with a spiral tip
should complete the paint removal. (Durall also makes a good degreaser.)