Even a novice in construction or repair work knows that if you put paint on an unprepared surface, it will quickly warp and begin to peel off. Proper preparation is almost the most important condition for the successful painting of any plane.
In order to extend the life of the products, construction primers were invented. Today there are many:
- primers for deep penetration;
- compositions that strengthen the painted surface;
- primers that prevent moisture absorption;
- mixtures that improve adhesion (adhesion of the paint to the surface);
- anticorrosive compounds;
- insulating.
If we classify primers according to the types of materials with which we have to work, we can distinguish:
- compositions for metal;
- primers for wood;
- universal mixes.
On sale today you can find ready-to-use formulations or dry mixes that should be diluted with water before work. Typically, the composition of the primers, recommendations and their scope are indicated on the packaging.
Impregnation for wood protective can be of two types:
- composition for working with transparent paints and varnishes;
- mixes for opaque varnishes and paints.
In the first case, the primer for wood should necessarily include a special film former, but there should not be any dyes or pigments in it. It is usually applied under transparent varnishes, as it perfectly emphasizes the structure of natural wood.
When choosing such impregnations, it should be noted that the substances that form the film are included in all primers. But in order to emphasize the beauty of natural fibers, it is worth giving preference to casein-rosin fillers. They do not split wood fibers, do not mask the pattern that they form.
Before painting the surface in any opaque color, the primer for wood (or universal), which corresponds to a specific paint, is more suitable for preliminary impregnation.
- For nitro enamels or oil paints, it is worth choosing the impregnation of the correct color. Most suitable compositions of cherry, fawn, brown or cream colors.
- For polystyrene paints, primers on the same basis are recommended.
- For facade or other outdoor work, an alkyd primer for wood is used. It dries almost instantly, fills the pores of a tree well, preventing the occurrence of rot or mold. If linseed oil and pigment are included in the composition, then the surface after impregnation can not be painted: the primer will give the tree aesthetics and preserve its appearance for a long time.
- An alkyd primer is chosen for the treatment of fiberboard, natural wood, chipboard. It prevents moisture penetration, improves adhesion, and extends the life of the painted surface.
Modern compositions for primers usually combine several qualities:
- Prevent aging and wear of wood products.
- Prevent them from drying out, delamination from the action of excess moisture, do not allow the appearance of cracks.
- Allow significant savings in paints and varnishes.
Primers for wood are used to impregnate previously painted, as well as new, not yet treated surfaces.
Before applying the primer, any (old or new) surface must be thoroughly cleaned, the remains of the old coating should be removed, and evened. If there are cracks or other defects on the tree, they must first be repaired with putty. When it dries, the surface should be treated with a solution of ammonia to degrease. Usually, a liter of twenty-five percent ammonia solution is dissolved in a liter of water to prepare it.
The primer for wood is applied on a flat, dry surface.