Choosing the Best Primer for Your Exposed Wood Painting Project

You have a wood painting project and wish to know more about primers and paints. A primer is defined as a paint coating designed to form a film upon which a succeeding finish coat or coats of paint may be applied. Since the outdoor environment places tremendous demands on paint, always purchase and use the best grade of primer and finishing paint coat you can reasonably afford.

Stain Blocking Primers for Your Decorative Painting Project

Stain blocking primers are formulated to prevent stain bleed-through which is a brownish or tan discoloration of acrylic latexpaint that can occur when the paint is applied over certain types of bare wood. Naturally, it can be quite unsightly on a white or light-colored paint as used on your wooden cow shaped step stool or any other indoor/outdoor wooden toy decorative painting project.
Stain bleed-trough commonly occur when tannin found in some kinds of wood, particularly cedar, redwood and mahogany, seep trough the paint and discolors it. Tannin, also called tannic acid, is a yellowish or brown substance that bleeds from certain woods. Stain bleed-trough can also occur when knots or sap streaks are painted over in any species of wood, including, of course plywood. To avoid stain bleed-trough, bare wood should be primed with a stain resistant primer. Even though these primers may themselves become stained, they will keep the wood tannin from bleeding into the topcoat, except in the most severe cases. The primer’s stain-resistant property should be noted on the label or in the manufacturer’s literature. For maximum protection, and for a superior topcoat, two coats should be applied to your decorative painting project.
These primers are specially formulated so that they will block the staining materials, which leach out from the wood. Stain blocking primers typically contain a high binder to pigment ratio, zinc oxide or other pigments that block stains, and thickeners that help the primer form a stain-resistant film.
For a superior result, insure that you purchase a product that is suitable for outdoor use and the type of wood you intend to use.
Also consider that the product you purchase is environmentally safe and user friendly, that soap and water can be used to clean hands and brushes.
Some Stain Blocking Primers are not suitable for plywood as used in wooden toys because they dry to form a rigid film that can crack with the slightest movement.
If you are using pine or fir board with no knots or defects, which could bleed through the finish, a stain blocking primer is not necessary. You can use a regular exterior acrylic latex primer.

Spot Priming and Your Outdoor Wood Painting Project

The advantage of stain blocking primer is its ability to prevent bleed through. If, for example, knots in the back of your plywood were the only area of concern, it would be entirely satisfactory to paint only those knots with a stain blocking primer. This is called “spot priming”. After the potentially troublesome areas have been spot primed a regular exterior primer can be used to finish your decorative painting project.

Acrylic Latex and Oil Based Primers and Paints for the Painting Project

Acrylic latex exterior primers are preferred for anything made of wood that is outdoors or might be used outdoors such as wooden furniture; toys and the cow shaped step stools. Gloss or semi-gloss acrylic latex exterior paint is recommended for the topcoats. As mentioned, latex primers and paints are more resistant to UV radiations and are less likely to blister than oil based primers and paints. This is not to say that oil-based primers and paints cannot be used. Oil based primers have their own advantages. For example they have better “hiding” capabilities, and therefore better coverage. They also have better adhesion to wood, as they penetrate the wood surface, and therefore seal the surface better. After considerable experimenting, we have found that, quality acrylic latex primer and paint to be the best choice for the painting project on the wooden toys and animal shaped step stools we make. The chart below outlines some of the advantages of latex versus oil paints and primers.

Acrylic Latex

- Drying time; Touch proof 1-4 hours
--Vehicle; Non-flammable, minimum offensive odor, environmentally friendly
---Fumes; Minimum risk of inhalation, for your comfort paint in a ventilated area
----Liquid used for thinning; Water
-----Clean-up; Warm water and soap

Oil Based

-Drying time; 24-48 hours
--Vehicle; Flammable, Toxic, mineral based
---Fumes; Toxic, will cause dizziness, good ventilation essential
----Liquid used for thinning; Paint thinner or turpentine, good ventilation essential
-----Clean-up; Paint thinner or turpentine, good ventilation essential

More Hints and Knowledge for Your Painting Project on Wood

Primer must be applied to bare wood prior to painting the final coats, usually at least 2 coats
Paint should not be used in place of primer. The reason is that the primer contains less pigment, this allows it to better soak into the wood for a more adhesive grip.
The primer is usually white, this is the preferred base color for most painting project applications on wood such as the cow shaped step stools, wooden toys, outdoor furniture, wooden window and door frames etc.

Shaking or Not Shaking the Paint

Not all primers should be shaken on a paint shaker. Some manufacturers specify that the primer or paint need little or no stirring, much less shaking. They say that all shaking does is incorporate air, causing foam, which must be dissipated before use, or you will have bubbles and craters in your finish. They recommend shaking their primers and paints only when adding tint color. Always read the manufacturer’s label and follow their recommendations and instructions before you buy as the shop attendant does not always know.

Avoid Heavy Coats on Your Painting Project

Don’t apply extra heavy coats of either primer or paint. An extra heavy coat will not necessarily offer better protection. In fact, coats that are too thick will probably crack, resulting in less protection, or form ugly runs and droplets. While it is sometimes difficult to judge on a small object, try to use the coverage guidelines, which the manufacturer has put on the label. If the label says that a certain quantity (a gallon, or a liter) of paint will cover a certain area (square feet or meters), try to estimate the surface area and spread the paint so as to use up a measured quantity. This will result in the thickness of coating the manufacturer recommended.
Since a painting project such as the wooden cow shaped step stool is an odd shape, almost impossible to measure, you can paint several test samples of the same wood at a different rate, mark them clearly and assess the achieved finish when dry.
Besides paint coverage, the label on your paint container will advise the correct drying time between coats. Always follow the label instructions as manufacturers put a great deal of effort into research and development of their paint products.
It is always pays to get into the habit of reading and following label instructions.
##Avoid well meant but often misleading advice from so called professional painters, such as using flat plastic interior paint and coating it with a clear lacquer, it might look good at first, but it will not last very long.

Selecting the Paint for the Top Coats of Your Painting Project Challenge

You will want to select the best quality of paint available for your painting project. The paint should also be compatible with the primer you have chosen, ideally from the same manufacturer to avoid paint incompatibilities such as: the paint does not want to spread properly, it is streaking and peeling off when dry or it does not dry hard, etc. (Henry can tell you some horror stories about using mixed bargain paints).
Look for exterior “trim” paint or “trim and shutter” paint. Trim paints are formulated for wood trim areas of the home. Other properties of trim paint include good leveling and therefore freedom from brush marks, rapid drying and good color retention. They are available in gloss or semi-gloss finishes and either is recommended for the wooden cows painting project.
When you purchase paints be sure to have your dealer shake them (Read the label, some paint do not require shaking).Shaking will insure that any pigment, which may have sunk to the bottom of the can, is resuspended.
Ask your paint dealer to fit some safety clips to the paint tin lid, as even a minor jolt can tip the tin in your car and cause a nasty paint spill (Vicky knows too well about the blue carpet in the red Camry). Also ask the paint dealer for some complimentary wood stir sticks. Use these wood sticks to mix the paint immediately upon opening the can to be absolutely sure the colour pigments are evenly distributed. If using a metal stick or a power mixer, such as an electric drill on slow speed with a mixer attachment on water based paint, be careful not to scratch the internal coating of the paint tin, as it can rust and cause an embarrassing paint leak, often several months later (like the ugly white patch on the floor in Henry’s workshop).
Many hobby wooden cow step stool makers consider the painting of the final coat to be the most enjoyable part of the whole project.

Always Read the Labels First

When buying paint for your wood painting project, always read the label first. Labels provide an amazing amount of information. Besides listing the directions for using the product, most manufacturers include safety information, storage and disposal hints. Below is a list of what you can expect on a label:

1.The Name of the Product such as: Exterior Acrylic Latex Gloss Trim Paint
2.Directions: The manufacturers go to a lot of work and expense to determine the best way for you to use their product. Be sure to read, understand and follow these directions.
3.Cautions: Read carefully to prevent any physical or health hazards.
4.The Manufacturer: The name, address, emergency number of the company that manufactured or imported the product.
5.Disposal: Spoilt paint and containers should be disposed of in an environmentally responsible manner. Unused good paint might be useful to a friend or neighbor, donate it.
6.Storage: Do not expose the product to excessive heat, keep in a dry cool place and keep from freezing.
7.It is a good idea to write on the tin the date of purchase and the color of the tint if applied. Also make a note of any anomalies or hints for your future use such as: this paint dries fast, wash the brush often and do not leave the tin open for any length of time. This paint does not spread evenly on a cold day. This paint needs to be mixed whilst the tin is standing in hot water (old paint?). This paint smells awful, ventilation required.

Useful hints for Your Wood Painting Project

--When storing your quality paint, ensure the lid is firmly closed, by perhaps stepping on the lid or using a mallet to tap down the edges of the lid.

--Store the tin upside down, yes I mean lid down, preferably on a few sheets of newspaper to prevent any soft paint sticking to your shelf or floor.

--If your tin of paint is less than 1/3 empty, and you plan to store it for your next painting project, mix the remaining good paint well and decant it into a seal-able glass jar, it will keep longer, better and you'll see the content. Store in a dark place.

--When painting complex and time consuming items, replace the paint tin lid immediately after loading your brush. This will prevent your quality paint from forming a skin.

--If your paint has gone lumpy or has particles of dirt or dry paint in it, fit a lady’s pantyhose leg over a clean seal-able container, ideally a glass jar, and pour the soiled paint into it. All the solids will be trapped in the pantyhose and you will have clean, usable paint in the container. Seal the container and store up-side-down to prevent any air getting into it.

We wish you happy painting.

Of interest. Our artist, painter and decorator Paul is on a discovery tour of India, near the Himalaya's, looking for amongst many other things, some exotic stock and ideas for our creations in wood and painting project, click here to read Paul's interesting travel blog. Paul has since returned from his wonderful 6 months experience in India with a fresh outlook on life. Unfortunately any exotic wood material for some of our projects was confiscated by customs on Paul's arrival back home, reason given: the possibility of pests and exotic seeds being present in the samples.

Paul is presently living in Melbourne where he practices his main vocation, Chinese Medicine. In his 'spare time' Paul teaches martial arts and studies for a degree in Building Biology, so we see him seldom. Regarding his creativity with a painting project, Paul has a new hobby and is now writing a book, title and subject unknown.