The first step to custom
paint panels is to apply a high-build, sandable primer.
- The idea here is to use a primer that will fill up the
minute scratches in the body-filler left by the 400 grit sand paper and
leave behind the perfect foundation for your first layer of paint.
The scratches left behind from sand will act as a "tooth" for
the first layer of primer to grab on to for great adhesion.
- In my projects, I use the highest build primer on the
market, Evercoat Slick Sand to custom paint panels. It is
more-or-less- a spray-able body-filler that is thin enough to spray
with a primer gun. Please note that you can use primer that
is applied from a spray can. Just make sure that it is
Apply your first coat of primer according to the instructions on the
- Most manufacturers will suggest that you apply the primer
in two or more medium wet coats. If the manufacturer tells
you to do this, you need to do so. However, in order to sand
the primer, after it dries you will need some thickness to be built up
in order to be able to sand it smooth without going through the primer.
So, even if the can says two or more coats, I would suggest
considering that to be just one coat (overall).
After the first coat of primer has completely dried, according to the
manufacturer's instructions on the label, scuff sand the primed area
down with 400 grit sand paper. Keep sanding until the primed
surface shows little to no "orange peel." Orange peel is the
technical term for the look of the paint after it has been applied and
resembles the texture of an orange peel (like a bunch of
little demples, or splatter).
It is easy to sand right through the primer you applied, so don't bare
down too hard with your sand paper. If you happen to sand
through your primer, like I did in the picture below, clean the area
and re-apply primer in the areas that you sanded through. Then re-sand
and continue to the next step to custom paint panels.
Clean and dry the area and apply your second coat of primer for your
custom paint panels. After it dries wet sand the area 600 grit paper.
I suggest wet sanding your second coat of primer because the
water/soap solution you use to wet-sand will actually lubricate the
surface you are sanding and will make the area smooth on a molecular
Next apply your third coat of primer and allow to dry. This
time you will want to wet sand the entire primed area with 600, or 800
grit sand paper. After sanding with the 800 grit paper, your
panel will be smooth enough (it will have a slight gloss afterwards) to
create a flawless finish with your color paint (base coat).