If you have any wood furniture, it is a great idea to be
familiar with the art of woodfinishing for all your
woodwork projects. There
are three basic finish steps to apply to all finishes, from the
most basic wax or oil finish to contemporary coatings and even
painting the exterior of a house or a room wall.
Paint, lacquer, varnish, oil, or even a wax finish can be
used on wood. The Base sealer or primer coat provides the
foundation of the finish. The Build coats provide the structure
or framework of the finish itself, much as the framing of a
house.
The Top coat gives the finish its final character,
whether matte or sheen is used. Remember that unlike metal or
plastic surfaces, wood presents a substrate that varies in
density, porosity, and stability.
The first thing to do is to prepare the surface of the
substrate in character with the desired finish result. If
an extra smooth surface is specified, then sanding, grain
filling, and defect filling of some sort will probably be
necessary. On softer woods and on face grain this sealer
coat may require two applications to provide an even base
for the build coats.
Build or body coats are the part of a finish that
provide moisture resistance, durability and longevity to
the coating. Depth in clear or translucent finishes and
richness of colored coatings depend on these build
coats.
Painting
woodwork for clear coatings, where the structure, grain
and tone of the wood are visible, use only gloss for build
coats. Goss body or build coats maintain clarity and
eliminate the foggy, dull or milky look associated when
semi-gloss.
With moisture, proof or moisture resistant coatings the
hardness or density and porosity of the wood substrate will
dictate the required number of build coats. The best
moisture proof coating cannot do its job if the coating
thickness does not provide for wear and a non-permeable
membrane.
When moisture resistance is important, always give at
least one more coat than just looks good or provides an
even build. The one extra gloss build coat added to a
finish consisting of one sealer, one build, and one topcoat
will more than double resistance to moisture. Solid opaque
lacquers and painted finishes, the gloss product has all
the best in hardness and durability characteristics
including resistance to dents and impressions
Many finishers, in a rush to this end, discard of the
foundation work that will provide the lasting look and
result in durable performance, however this has. This top
coat gives the desired esthetic sheen, but the total look
and character of the finish comes from the work put into
the first coats.
Careful preparation prior to this last coat by sanding
with fine paper, careful removal of dust from the surface,
and sanitation in the work area pay off in a lot of saved
labor.