kept clean. Spray gun tips (orifice)
will wear, and as they become larger,
inconsistent finishing will result.
• All excess stain should be wiped
off uniformly to prevent adhesion
problems and color inconsistencies.
• Heavy-bodied stains must be
dried properly before the next coat is
applied in order to reduce the threat
of bubbles and blisters.
• After wiping and drying, the
stains should be brushed or blown off
to remove any excess rag fibers, lint or
• All clearcoats, washcoats, sealers and
topcoats should be applied at wet film levels to obtain the best finish appearance.
As a general rule, I recommended 3 to 4
wet mils for low-volume solids.
• It is recommended to keep the
sealer application closer to 4 wet mils
and topcoats closer to 3 wet mils. In
faster manufacturing situations, this
helps to prevent blisters when the finish is exposed to heat. Millage control
of the sealer and topcoat application as
recommended by a finishing supplier
should be monitored carefully and
closely every production day. Excessive
millage results in too much film, which
causes checking and crazing of the
finish. Not enough millage, or missing parts of the furniture or cabinet
in the application process, allows for
moisture seepage, or the finish being
compromised from household items.
• In the more simple finishing
operations, pieces should be examined
for wood finishing defects as early as
possible, best to go no later than the
sealer application stage, prior to top-
coat application. It is easier to adjust
sealers than rectifying poor build or
poor color in the topcoat step. Sealers
can be tinted and - depending on their
formulation - sanded in preparation
for the final topcoat. Therefore, catch-
ing finishing problems before the top-
coat application is a rule that would be
good to follow. Quality inconsistencies
after the topcoat is applied will require
a more costly repair operation, both in
time and money.
• It is recommended that finishing
materials be properly warmed before
application, especially in cold climates.
Checking for flow properties is important for all wood finishing products,
especially clearcoats. If the materials
are cold, the viscosity will be high and
the quality of the finish will be compromised; if the finish is too warm,
flooding of the finish (leaving puddles
during application) may occur.
Wood finishing is a combination of
science and art. By combining fashion
and durability properties, the wood
finish serves as an “envelope” to beautify and protect the wood.
Wood finishing is one of the last
processes in the manufacture of furniture or cabinets and the first thing
seen on the retail floor. The finish triggers consumers’ emotional responses
to the senses of sight and feel. The
finish can accentuate the beauty of the
wood or can cover up wood substrate
Robert Cox Jr. is the former president
and CEO of The Gilbert Spruance Co. and
Spruance Southern Inc., with 40-plus years of
industry experience. Email him at robertcoxjr@
Wood finishing is one of the last processes in the manufacture of furniture and cabinets and is
the first thing seen by consumers in the showroom.