Aerosol cans of shellac, lacquer and polyurethane allow you to quickly apply a finish on small or complex projects that's free of brush marks. Learn the basic techniques that guarantee a good finish.
By the DIY experts of The Family Handyman Magazine:May 2008
Spraying is fast and gives a smooth
finish, but it also creates a fine mist
of solvent and finish that drifts and
settles on everything in sight and is
dangerous to breathe. To avoid
problems, work outdoors if possible.
If you spray indoors, cover everything
with plastic sheeting or drop
cloths and wear a respirator fitted
with organic vapor filters, especially
if you’re spraying lacquer. Also put
an exhaust fan in the window. Read
the label on the spray can for additional
It’s hard to get even coverage if you start or stop
spraying on the surface you’re coating. The spatters
that happen when you first push the button
can blemish your work, and spray builds up in
one spot if you don’t move fast enough. An easy
and foolproof way to avoid these problems is to
start spraying before you reach the edge of the
project, move across the project at an even pace,
and stop spraying after you’ve gone past the far
edge. This technique guarantees an even, spatter-
free coat of finish across the entire surface.
It's natural to swing the spray can in an arc, but this
results in uneven coverage. The finish will build up
in the center and be light on the edges.
To get even coverage, overlap the
spray about halfway onto the previously
sprayed section. If you just overlap
the edges, you'll get a narrow band
of thicker finish where the two strips
meet. Overlapping at least 50 percent
solves this problem—you'll apply
about the same amount of finish
Focus on keeping the spray tip an equal distance
from the surface as you move it along. At the same
time, keep the can moving at a steady pace to get an
even coat. The goal is to apply just enough finish to
wet the surface without creating runs. Prevent runs
by applying several thin coats rather than one or
two thick coats. The finish may look blotchy after
the first coat, but additional coats will produce a
If you've ever used spray cans to
finish a large project, you know
how sore your fingertip can get
from pressing down on the spray
tip. A spray-can trigger handle
saves your finger and gives you better
control of the spray. You'll find
spray-can trigger handles at home
centers and hardware stores.
Spraying a heavy coat of finish over a dark
stain or over some oily exotic woods can ruin
your project’s appearance. The solvent in the
finish can dissolve the stain or the color in the
wood and cause it to bleed or get muddy looking.
To avoid this, prime these types of projects
with several thin mist coats before applying a
thicker coat of finish. Apply a mist coat by raising
the can higher than normal and moving
the can faster than usual. This
will reduce the amount of
spray hitting the surface.
Mist coats dry quicker than
a full coat, so you can typically
apply several mist
coats with less-than-normal
waiting time. Wait for
the previous coat to dry to
the touch before recoating.
Dark, oily woods or stains can bleed into lighter wood.
At $4-plus per aerosol can, it gets pretty
spendy to build up a heavy, protective layer of
finish on a large project. But you can still take
advantage of the flawless finish provided by
aerosol cans. Start by applying two coats of
finish with a brush. Then carefully
sand with 220-grit sandpaper and
remove all dust before using spray
cans for the final coat. If you don't
know much about finishes, just
make sure your liquid
and spray finishes
are the same
When you have a small project with many
sides to spray, placing it on a turntable will
speed up your job and make it easier to get
good results. Instead of trying to move
around the project as you spray, just give
the turntable a little spin. You can build a
turntable like this by mounting lazy Susan
hardware to a scrap of particleboard or plywood,
and then mounting a plywood or
particleboard disc to the hardware. Lazy
Susan hardware is available at
hardware stores and home centers. Check
the instructions before leaving the store so
you can pick up any screws you'll need.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
You'll need an organic vapor respirator and a spray can trigger handle.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.
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