SAIL - April 2015

PROJECT—PART II

BOAT

WORKS

Sometimes choosing the finish paint is the hardest part of the

entire paint process, not only because of the various types of paints to

consider, but because of the equipment needed, whether or not you

have a place to perform the work, and whether you have the necessary

skills. Planning the paint job is just as important as applying the paint

itself, so make sure you contact the paint manufacturer and get all the

information that you can in advance so you will have the confidence to

do the job right.

WHICH FINISH?

There are several types of paints used to paint boats, which tends to

become confusing. For most sailors there are essentially only two types

to choose from—one-part and two-part paints. However, within these

groups there are differences between the types of resins used, the applica-

tion methods and the longevity of the coatings.

ONE-PART PAINTS

When it comes to one-part paints, there are three main options out

there. The first employs alkyd resins, which are sometimes referred

to as enamels. A typical alkyd paint consists of a resin that has been

modified by an oil such as tung, linseed or castor oil, to form the coat-

ing film. Solvents, driers and pigments are added to make it easier to

apply, dry properly and to provide color and hide (i.e. the ability to

obscure the surface they are covering). These paints were developed in

the 1920s and are still in use. They have a good gloss and hide, and are

easy to apply. However, they do not have the longevity of more modern

coatings and will need to be recoated sooner

Silicon-alkyd resins, on the other hand, are alkyd resins that have

been modified with silicon to add longevity. They were originally

developed to be used as maintenance coatings on steel and concrete,

but quickly found a use on boats because they provided a finish with

greater longevity and a higher gloss than simple alkyds. Silicon-alkyd

resins are easy to apply and have good hide, but they are more expen-

sive than straight alkyds.

P

rofessional applicators know that the preparation

and priming stages of any paint job (covered in last

month’s issue) are the most important and will take

80 percent of the time spent on a paint job. But they also

know that what they get paid for is the finish. Once you

have completed the preparation and priming stages, the

next step is the application of the paint itself. This is where

all of your hard work pays off.

Part 2: The ins and outs of getting a perfectly finished topcoat By Jim Seidel

A New Coat

A new paint

job can give

your boat

a new lease

on life

58

APRIL 2015 PHOTO COURTESY NEWPORT SHIPYARD