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This is an excerpt from an article in the June, 2000 issue of
Woodworker's Journal.

Picking the "right" finish for your most recent woodworking
triumph may seem like a daunting task, given the confusing array
of choices. To make the correct choice, start out by answering
three primary questions before you begin:
1. How durable does the finish need to be;
2. What kind of appearance do I want; and
3. What's the best application for me?
Durability
Durability is the first thing you should determine. Ask yourself,
"what must this finish endure." An art turning can get by with
nothing more than a coat of oil. A kitchen table or countertop,
which needs to endure hot coffeepots, scratches, stains, and
even chemicals and strong cleansers, will require something much
more durable. Patio and outdoor furniture will need a finish
that can stand up to temperature and humidity variances. Salad
bowls and cutting boards need a special "salad bowl" finish,
which is specifically made for objects which come into contact
with food.
Durability is also affected by how thickly a finish is applied.
A very thin finish regardless of the type, will not protect as
well as a thicker application of the same finish.
Appearance
Staining, of course, changes the color of the wood, but clear
finishes will also alter the appearance of the wood. Most
waterborne lacquers and polyurethanes are completely clear to
slightly blue-gray. They will add almost no color to white woods
such as maple, holly, and spruce. Shellac and lacquer will add
warmth and color to the wood. Oils (including Danish Oil, Tung
Oil, and oil-based poyurethanes) generally add the greatest
amount of amber tones to wood, especially when several coats are
applied.
With figured woods, such as curly or bird's eye maple, you can
actually use the finish to intensify the figure, or "pop the
grain," even without staining. One of the best "grain poppers"
around is boiled linseed oil but shellac, lacquer, and most
oil-based varnishes will also do the trick.
By adding one or two coats of shellac to a piece of figured
wood, you can achieve a stunning effect called "chatoyance,"
from the French meaning "like a cat's eye." If you've ever seen
the semi-precious stone Tiger-Eye, you'll notice that as you
change your viewing angle, the light and dark bands of color
change places; this is chatoyance.
Application
Most finishes can be applied in a variety of ways. Shellac, for
instance, can be wiped on, brushed on, or sprayed on. The same
is true of Danish Oil, varnish, and most waterbornes. Some
finishes, however, lend themselves more to one application style
or another, and others are formulated for a particular
application method.
Waxes and gel finished are specifically designed for wipe-on
application. Though nearly every varnish or polyurethane can be
wiped on instead of brushed on, some are designed for easy
wiping and thin application. This will usually be stated on the
can.
Certain lacquers and conversion varnishes are designed for
spraying and will dry too fast if applied with a brush or rag.
To help you choose the right finish using Dresdner's
"Appearance, Durability and Application" approach, we've made a
comparison guide of all our carefully selected finishing
products. See our
Finishing Matrix for a complete chart of products.
Michael Dresdner is a nationally known finishing expert and
author. This article originally appeared in
Woodworker's Journal May/June 2000 issue. For a free
trial issue, visit
www.woodworkersjournal.com.
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