Spraying Aerosols tips
A spray can is technically known as an "aerosol"
device that consists of the outer can and a spray nozzel.
Today's spray nozzles are really quite good. They are precision-engineered to
provide a high-quality spray, with consistent droplet sizes. That said to get the best finish it's important to use the aerosol properly so you too can get smooth, shiny results!
Spray paints are heavily thinned (more solvent-to-paint content) in order for them to be pushed out of the can and turned into an aerosol spray. Thicker paint would require greater gas pressure and a more sophisticated nozzle, hence leading to an air-powered paint gun. The "trick" to getting good results with thinned paint is simply to remember that it is, in fact, thinner and proneto runs. That means more thin coats.
Common user errors some of which include holding the can too close, too far away, for too long in one spot, moving too
fast, too slow can result in a less than desired finish. Below we focus on some tips to di it right. Lets paint!
First we must make sure our work piece is ready for painting. Ensure it has been sanded, smoothed and primed. After that sand again with fine (600 grit or higher) paper. Just before painting wipe it again with solvent on a paper towel. If you can place on a table or surface that allows it to be high enough to see clearly during spraying (we prefer to hang items from the ceiling joists with string and bent pieces of wire). Lastly make sure there is plenty of light around the work piece.
Lets spray!
Tip # 1- Shaking the can long enough!
Now it's time to shake the paint can, a trick for new players is doing so only until the ball rattles, which it usually isn't. The paint pigments have most likely separated during storage, so they need quite a bit of agitation to
properly mix again. Unless you've used it that day already, a good practice is to shake for at least three minutes after the ball starts rattling. Test the spray on a piece of cardboard or paper.
Tip # 2 - Holding the can the proper distance!
Spray can directions tell you how far away from the work piece to hold the nozzle. That distance is to
provide the best spray pattern and most equal distribution of the paint. Test that effect on your cardboard and prove it to yourself. What the manufacturer tells you is true.
Spraying too far from the surface puts less of the paint on the surface and the paint can actually start to dry out before it reaches the surface, leaving a rough texture or dull finish to the paint.
Tip # 3 – No holding the can directly in front of your face!
It becomes very difficult to see how the paint is "wetting" the surface if the can is spraying
directly in front of your eyes. If you are right-handed, hold the can at chestheight about one foot to the right of your head (the reverse if left-handed).
As you spray you will be looking at your work piece at a "grazing incidence" angle and will easily see how the spray is falling onto the surface. Spraying at the distance suggested on the can's label gives you control over the paint and helps prevent excess paint buildup which can lead to runs.
Tip # 4 - Moving at the right speed!
Once you can see the "wetting" effect; that is, the paint falls onto the surface and just starts to become shiny, it's
time to move the can along the surface. Keep it moving at all times and the correct speed is that in which the volume of paint coming out wets the surface. Moving too fast applies a "dusting" of paint that is too little for the components to "float out" to become a smooth surface. Too slow applies the paint too thick and because it is a thin fluid can cause paint to start to run
and drip.
Tip # 5 - Staying parallel to the work surface!
You must move the canparallel to the work surface at all times. Not doing so alters the distance from the nozzle to the surface, creating the mistake in Tip # 2 again. Practice with the can before actually spraying so you know you can move easily over a
large area.
Tip # 6 - There's no such thing as "one coat.
Good paint finishes are alwaysbuilt up from multiple layers of paint, each one applied on a "still tacky" surface. The idea is that the paint you sprayed 10 minutes ago is still uncured and soft, so the new coat will not only stick well but its solvents will
tend to "re-melt" the last coat and allow the finish to create a smoother, flatter surface.
Tip # 7 - If you get it wrong don't stress. Dust got in the finish.. runs appeared.. "orange peel" appeared.. or something else affected the outcome, don't stress. If this happens and you are unhappy with the outcome, just stop and let the paint dry. Sand everything smooth with 600grit or higher sandpaper and put on a couple more coats. If the project looks very average (or worse), spread on the paint stripper and get the work piece back down to bare surface. Fresh paint comes off very easily and you can re-do the whole thing in short order.
Points To Remember":
A little practice goes a long way, so if you're not experienced at spray painting take some time to practice painting a "test" piece. Use a piece of cardboard covered with aluminum foil if you don't have a sheet of metal or plastic to practice on. Plan to waste the better part of a can of paint in the process.
Shake the can periodically while you paint to keep the materials in
proper suspension.
Don't forget to invert the can when finished, spraying until all color
disappears.
Mount your work piece on a stand or hanger if possible that makes it
easy to rotate or otherwise change its position, so that you can get a
more even finish overall.
Keep the nozzles on your paint cans clean. If they are clogged, pull
them off and soak for a few hours in lacquer thinner.
Custom colour paint cans only designate colour formula on a label
stuck to the can. Write this down somewhere or take a photo of the
label for later reference.
Safety:
Paints are often made from toxic substances, and their solvents can be equally as dangerous. Ventilation and breathing protection are very important. When painting indoors you must make sure you have good ventilation. Wear a proper filtration mask that removes organic vapors. If you feel dizzy, nauseated or disoriented while painting, stop and get some fresh air.
Colorpak safety datasheets are listed on this website.