Car primer - choice of color, application nuances

In preparation for finishing, the solution was poorly mixed. Heavy elements of paint remained at the bottom of the can, and the rest fell into the spray gun. And if the container was vigorously shaken, then the liquid mixture will still be with air particles.

When performing body work, it is important to know how to choose a primer for car paint. If the coating is applied incorrectly, then the painted areas will not only look ugly, but also resist corrosion worse.

Causes of Low Coverage in Automotive Paints

Many of the defects that appear on the repaired surface are due to the inexperience of the painter, the use of low-quality products, or the violation of staining technology.

The concept of hiding power and paint consumption

In order for the distinguishable contrast of the substrate on the car body to disappear, it is important to take into account the ability of the paint to make the old coating invisible. This parameter is called opacity. It is measured in grams or milliliters per square meter. m area and directly depends on the quality of the pigmented mixture. The better it is, the less paint consumption will be to create a surface of a certain color and physical and mechanical properties.

According to GOST, the covering power is considered complete if the ratio of the white to black substrate exceeds 0,98.

Body priming

According to experts, even with the most spectacular mixture, you will need at least 2 layers to hide the base of a different shade.

The problem of poor coverage

Quite often, motorists are faced with the fact that traces of the previous layer are visible through the tinted area: stripes or spots appear. This phenomenon is primarily associated with the use of incompatible paintwork in tone and saturation.

For example, in the repair area, a light gray color of the primer was used under the silvery paint of a dark metallic.

Due to the low contrast ratio of these shades, the substrate will show through the coating. To make the area invisible, you have to spend a lot of paint. But if you choose the right primer tone, then you would have to apply fewer layers of paintwork materials.

In addition, poor hiding power is most pronounced on the car body, where there are sharp corners and edges. In these hard-to-reach places for the sprayer, the paint does not get enough.

The main problems of poor hiding power:

• excess consumption of liquid pigment mixture;
• prolonged drying of the intermediate coating;
• poor strength and adhesion of the entire paintwork material due to numerous layers of soil and base;
• inexpressive lacquer gloss.

This is often encountered by auto painters. There are several reasons for these negative effects.

In preparation for finishing, the solution was poorly mixed. Heavy elements of paint remained at the bottom of the can, and the rest fell into the spray gun. And if the container was vigorously shaken, then the liquid mixture will still be with air particles.

Uneven paint spray. As a result, the thickness of the paint will be different (especially in the area of ​​joints and seams). This is typical when the coating technology is violated and when working with improperly configured equipment.

Car door primer

Drying of intermediate materials without following the recommendations of paint manufacturers. This causes the top coat to dissolve with droplets of the "wet" primer thinner.

And the last factor of poor hiding power is the polishing of the uncured coating and the use of incompatible products for processing. As a result, the top layer of paintwork materials is partially removed.

Primer properties for cars

The principle of operation of the composition depends on its purpose. Main characteristics:

• Passivating. Serves to oxidize the surface. Necessary to prevent corrosion processes.
• Phosphating. Forms a layer resistant to moisture and temperature fluctuations with the help of acid.
• Protective. It forms a galvanized surface that protects the base metal.
• Modifying. It is applied to the rusted area at a temperature not lower than 15°C.
• insulating. Provides water resistance.

So that the soil does not collapse from natural phenomena, it is covered on top with either a base material or a top coat.

See also: How to remove mushrooms from the body of a VAZ 2108-2115 car with your own hands

How to choose the right primer for the color of the car

The substrate should be taken taking into account the covering power of the base material. If you plan to paint the car in achromatic colors that have a maximum contrast ratio, the shade of the intermediate layer does not play a role, provided that a certain layer thickness is observed. But for the best effect, observe the following rules:

• The color of the primer for black paint should be the same as for any dark topcoat.
• If a mixture with poor hiding power (blue, red, pearl) is used, then the applied intermediate layer is optimal with different shades of gray.

To make it easier to choose the color of the primer to match the color of the paint, you can use the manufacturer's recommendations. An alternative option is to buy a “lining” similar to the factory one. You can find out its shade during the polishing of the coating.

If you know how to choose a primer for car paint, then there will be no translucence of the intermediate material and problems with adhesion of paintwork materials. To do this, you need to buy material, taking into account the hiding power of the finish coating.