Repair painting defects. Problem - bubbles on the painted surface Bubbles appeared after painting

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Painting is one of the most complex species bodywork repair work. It takes a lot of patience and effort to make a paint job truly durable and attractive. You can’t do without special tools. If a car is painted without following the technology, after some time defects may appear on the surface. Next, we will talk about exactly what problems arise when painting with a spray gun and how to successfully solve them.

Problem #1: boiling varnish or paint

An example of boiling varnish or paint. Click on photo to enlarge.

The reason for the appearance of bubbles in the thickness of the paint may be the following mistakes made during painting:

incorrect setting of the spray gun, as a result of which it feeds excessively a large number of paints;
improper dilution of paint, resulting in it being too viscous;
slow movements with the sprayer, as a result of which a too thick layer of paint is formed on the surface, or too much overlap of the previous layer with the next one.

To eliminate such defects, the pigment is completely dried, then sanded and another layer is applied - the finishing layer.

Problem #2: cloudy paintwork

The main reason for a cloudy surface is moisture getting into the paint during its application. How and why does this happen?

painting is carried out in a room with low temperature, high humidity or an improperly organized ventilation system, causing drafts;
a low-quality or incorrectly selected solvent is used. If the room is cold and humid, you should use a special product, and in a minimal amount, otherwise the paint will take a very long time to dry;
When painting, an incorrectly adjusted spray gun supplies too much air, causing the solvent to evaporate too quickly, the painted surface to cool, and condensation to form on it.

Elimination of paint defects associated with clouding of the coating requires increased temperature in the workshop and the organization of proper air circulation. You should wait until the pigment has completely dried, then spray a special solvent onto the defective area. For achievement maximum effect the surface is polished.

Problem No. 3: the appearance of craters

Craters - small funnel-shaped depressions in the paintwork - are formed for several reasons:

the surface was not properly prepared for painting, in particular, it was washed with soapy water or liquid detergent, as a result of which traces of silicone remained on it. They are subject to mandatory removal;
during the preparatory work the surface came into contact with dust, fluffy rags, polishing paste and was not properly cleaned;
Oil got into the spray gun air duct.

There is only one way to deal with craters: sand the surface and apply a new coat of paint.

Problem #4: Cracks in the paintwork on sharp edges

Immediately after painting or after some time, defects in the form of small gaps and cracks may appear on sharp bends of parts. The reason may be one of the following shortcomings during painting:

applying paint in several layers without intermediate drying, as a result of which solvent accumulates in the thickness of the paint. This is what causes cracking;
use of poorly mixed paint and incorrectly selected solvent. If the paint is not well mixed before application, the pigment will be distributed unevenly and the coating structure will become spongy. If you made a mistake in choosing a solvent and chose a composition that is too fast-acting, you may encounter significant difficulties: the paint will adhere very poorly;
poor surface cleaning before local painting, as a result of which the primer, and with it the paint, will “slide” from the bends of the part due to low adhesion;
blowing the primer layer with compressed air immediately after its application, promoting rapid drying of the coating, but preventing complete evaporation of the solvent and the release of excess air.

Such defects are eliminated by removing the top layer of paint and applying a new one.

Problem No. 5: “shagreen” or “orange peel” on the body of your car

Shagreen on the body of a car. Click on photo to enlarge.

The appearance of this defect can be caused by various reasons:

incorrect setting of the spray gun or non-compliance with the painting technology (unregulated pressure, weak paint supply or too large a distance between the nozzle and the surface, etc.);
too much heat in a repair shop. Such conditions require the use of special slow-evaporating solvents;
insufficiently thorough mixing of the painting composition and its non-compliance with viscosity standards;
too thin layer of paint;
painting in several layers without intermediate drying or drying with compressed air.

In this case, paint defects are eliminated by sanding with abrasive sandpaper (the grain size depends on the degree of damage to the coating) followed by polishing. In the most severe cases, it may be necessary to reapply the final coat of paint after sanding.

Problem #6: varnish or paint smudges

An example of paint smudges. Click on photo to enlarge.

Smudges are one of the most common defects when painting, especially if it is carried out by a non-professional. They occur if:

paint is applied too thickly or without drying each layer before forming the next;
the air supply from the spray gun was carried out under excessively high pressure;
paint supply speed exceeded;
The gun nozzle is too close to the surface.

In most cases, it is possible to get rid of smudges by grinding and polishing, but sometimes repainting the surface is required.

Problem #7: dusty deposits

If the painting technology is violated, dry and semi-dry drops of paint may stick to a freshly painted surface. The main reason for the appearance of such a defect is the use of a quickly evaporating solvent in warm and dry air conditions in the workshop, as a result of which the paint dries very quickly. In addition, the reason for the sprayer supplying semi-dry paint may be its incorrect settings or a violation of the technology, namely overspraying onto adjacent areas that are not to be painted.

If a defect has formed on the varnish, it can be easily removed by sanding. Plaque on synthetic enamel is much more difficult to sand off, so it is recommended to sand the surface “wet” and then apply a new coat of paint.

Problem #8: Porous surface

Pores - small holes in the paintwork - appear for several reasons:

the spray gun is incorrectly configured or used incorrectly (insufficiently intense spraying or painting too close range from the surface);
the presence of drafts in the workshop: air gets inside the paint and speeds up its drying, while all the solvent does not have time to evaporate;
varnish or paint is applied to a layer formed using “dry” spray technology;
when fed from a gun, the paint becomes contaminated with oil or becomes moist;
insufficient drying of intermediate layers, especially when working with “heavy” coatings;
incorrect technique for working with a putty knife;
incorrect choice of area for puttying or painting.

Troubleshooting

If the damage to the surface by pores is minor, it can be removed using fine-grained sandpaper. More severe cases may require wet sanding and reapplication of a final coat of paint or varnish. It will be possible to get rid of too noticeable pores only after sanding to metal and re-painting.

If we're talking about about a layer of putty with pores, then it should be covered with another layer, while the putty knife is directed strictly perpendicular to the surface to ensure maximum filling of the pores with putty.

In order to prevent the appearance of pores on the paintwork, it is recommended to keep under strict control the temperature in the workshop, the viscosity of the paint, the type of solvent - in short, everything that affects the drying speed of the paint.

Problem #9: garbage and dirt

Foreign particles on the paintwork appear due to:

using an unstrained working mixture of paint and solvent;
the presence of grinding dust on the surface to be painted;
settling of dust and other particles;
Low quality filters,
insufficient cleaning of the gun before painting.

Elimination of this defect is carried out by stripping the coating to an undamaged layer and then applying the finishing layers of paint again. Cleaning is not carried out only if the foreign particles on the paintwork are frozen drops of paint sprayed from a gun.

Problem #10:

An example of a sharp color transition. Click on photo to enlarge.

This difference is especially noticeable when painting damaged areas locally. A clear border of colors or color distortion is a consequence of such defects as:

poor mixing of paint;
applying paint in a layer that is too thin so that the primer shows through;
violation of metallic effect painting technology;
interaction of old and new layers of paint.

In order to smooth out the color transition, the surface is treated with fine-grained sandpaper and then covered with another layer of paint.

Torch imprint issues

Upper and bottom The torch sprays too much paint. This means that the paint or air nozzle is clogged or damaged. After repeated testing with the torch rotated 180°, the nozzles are cleaned and, if necessary, replaced with new ones.

A stream of paint forms a curved spot on the surface, similar to a banana. This defect indicates that the air nozzle is dirty or damaged. The malfunction can be eliminated by cleaning or replacing the nozzle.

The flow of paint is interrupted. There is air in the paint line. In this case, you should check whether there is enough paint in the spray tank and whether the paint nozzle is loose.

There is excess ink at the top and bottom of the print. The problem is solved by reducing the paint supply, which, in turn, is achieved by adjusting the needle and the intensity of the air supply. You can also replace the nozzle with a smaller one. The cause of this defect may also be a malfunction of the needle or screw.

The torch imprint is divided into two parts. The situation can be corrected by increasing the paint supply or reducing the air supply. In addition, you should check whether the vent in the tank.

Not enough paint in the center of the spot. The reason for this defect is that the ratio of paint and air supply is disrupted. To return the torch print to its normal shape, you should adjust these settings.

Lens-shaped spot. This malfunction is also associated with incorrect paint supply and air pressure settings. In addition, the reason may be that the paint viscosity is too high. The problem can be solved by adjusting the spray gun and diluting the paint with a solvent.

Errors when painting a car do not always arise due to equipment or characteristics of the paint material. Great importance have both the preparation of the surface to be painted and the equipment used. Sometimes car paint defects appear due to the negligence of the owner who did not check the conditions for the work. The quality of the paint coating also depends on the sterility of the spray booth or equipment.

Serviceable painting equipment is a guarantee of successful painting

Most common reason paintwork defects – wear and tear of painting equipment. Due to these malfunctions, the paint torch changes, on which the uniformity of application of the coloring material depends. The spray gun is unsuitable for use in case of the following malfunctions:

The ability of the compressor to supply the required pressure at the spray gun outlet also affects the quality of work. If the compressor is unable to provide a pressure of 3-5 bar, painting the car will hardly be possible. Viscometers, thermometers and pressure gauges also play an important role in the process by monitoring viscosity, pressure and temperature. The painting result depends on the accuracy of their indicators.

System providing air flow for uniform spraying, includes a compressor with pressure gauge and condensate release valve, dryer, pressure regulator and filters for separating water and oil. The absence or incorrect operation of one of the listed components in the system leads to coating defects. Pay close attention to these things.

When technological requirements are not met

Failure to follow the instructions for certain painting materials, which consists in mixing components from different manufacturers, is the most serious mistake and the cause of defects. The result is puckering layers of paint that need to be removed. The use of nitro thinner in quality universal remedy also leads to many coating flaws, so it is better to use compatible paintwork materials.

Painting defects often occur on the car body due to the fault of material manufacturers. In batches of coatings produced in different terms, viscosity levels may vary. In addition, poorly cleaned and dried containers can cause water or oil to appear in the paint.

10 typical car paint defects

These defects are formed if the brand of thinner does not match the type of coloring material. As a result of the reaction, “flakes” may appear in the paint, precluding its further use.

There are several reasons for leaks:

The basis for the formation of such a defect is the following factors:

4. “Shagreen”

Effect orange peel manifests itself as a result of the following shortcomings:

If light shagreen stains cannot be avoided, then to eliminate them you can try sanding and polishing the defective area.

Reasons why varnish does not adhere to the surface:

6. “Curling” the varnish

The varnish “curls” in places because:

7. Change of original color

Occurs when the following errors occur:

Small holes occur when:

9. Visible joint where the colors transition

This defect can be avoided if the surface is polished with sandpaper before painting. The finished area is painted, then subsequent layers are applied by spraying, each time expanding the boundaries of the painting area. The area painted in this way will be invisible.

Matt spots appear on the painted surface of the car if:

Rules for successful car painting

The rules are quite simple, and if you follow them, the procedure for removing paint defects can be avoided.

Very important preliminary preparation surfaces. It is thoroughly cleaned of dirt and rust, sanded old paint, and then dried. After degreasing, it is not recommended to touch the surface.
The sanded surface must be treated with anti-corrosion.
The optimal temperature for painting work is +18-20 °C. If work takes place outdoors, then the car needs to be warmed up.
The hardness of the water used should be minimal. The remaining moisture on the surface to be treated must be wiped off, otherwise the salt contained in it will cause defects.
Must have clean and dry compressed air under a pressure of 3-5 atmospheres, with regular cleaning of the water separator.
When using secondary priming, install a nozzle in the spray gun with a diameter of 1.5-1.8 mm, and when spraying enamel - 1.1-1.4 mm.
Use drying and painting booths if a system is connected to them fresh air and a dust filter with the ability to remove steam is installed. Otherwise, when painting, dullness or dust may settle on the surface.
The subsequent paint layer is applied only after the solvent has completely evaporated, otherwise the coating may “boil”.
When mixing paints and varnishes, strictly observe the proportions, viscosity, and the time interval between application of layers.
To sand intermediate layers, use paper of a certain grain size.

Having completed the repair of his car, the car owner is not always satisfied with the result obtained. What is the reason for the dissatisfaction? The fact is that, having spent a lot of effort and money, I discovered defects in the car’s paint job.

Often, this happens if the master does not have the proper experience in working with sensitive paints or the preparation for painting was carried out incorrectly. Such defects can occur both during painting, and before it and after completion of the work.

Painting defect "Flakes"

One of the most common defects is the formation of flakes. Its reason lies in the incompatibility of the thinner with this type of paint. In this case, the paint forms so-called “flakes” and actually becomes unsuitable for further use.

Painting defect “Smudges”

Defects in car painting often include another unpleasant moment - smudges. This happens if the paint is too liquid. It easily assembles into paths that flow along the vertical and inclined planes of the body. And this is not the only reason for this defect.

Leaks can occur due to the following errors:

1. The paint is applied too thickly. At the same time, the coloring material itself takes a very long time to dry.

2. The paint is thinned too much. Or the solvent acts very slowly.

3. The spray gun is too close to work surface. A distance of about 20–25 centimeters is considered normal.

4. The spray gun moved along arc trajectories.

5. Low temperature of the working surface or environment.

6. The varnish was unevenly absorbed by the base.

Painting defect "Grain"

The result is often a rough, grainy texture. The reasons may be:

1. While painting or drying the surface, dust settled on it. It is because of this that it is recommended to paint the car indoors, with excess pressure and without drafts. If the room has a cement floor, it is recommended to wash it thoroughly before painting.

2. The paint has not been filtered, and yet it contains solid particles. Remember that when pouring paint into the tank of a spray gun, it must be filtered to remove possible films and solid particles.

3. The paint was sprayed from an unacceptably large distance. To avoid problems, it is necessary to blow dry air onto the painted surface.

Painting defect “Shagreen”

Often there is a defect resembling an orange peel. When is the car painted? , shagreen occurs for the following reasons:

1. The thinner evaporates very quickly. Try to select thinner according to the size of the object, air movement in the room and temperature.

2. Varnish and thinner are incompatible with each other.

3. The varnish is not diluted enough. The proportions of the mixed components should be carefully observed, using measuring rulers for this.

4. The paint does not spray well. Defects in car painting are most often due to the fact that the compressed air supplied to the paint sprayer is uneven.

5. The distance from the spray gun to the surface to be painted is too large.

6. The ambient temperature in the room where work is being done is significantly higher than the temperature of the surface being painted. The best temperature is +20 degrees C.

7. Layers of paint are applied without observing the required drying time.

8. A spray gun with a nozzle that is too large is used for the job.

What should you do if you have already completed painting your car, have shagreen on your face and need to get rid of the defect? Light shagreen can be removed by sanding and polishing. Pronounced shagreen can be removed only by cleaning the defective area and doing the work again.

Painting defect “Peeling of varnish”

The following car painting defects are peeling varnish:

1. Before applying varnish, the old paint was not thoroughly cleaned off.

2. Varnish and undercoat are incompatible.

3. Varnish is applied to metal, without using a protective coating.

4. Rust has not been completely removed. As a result, moisture passing through the capillaries provokes further rusting and causes the paint to lift.

5. Drying after sanding with water caused the precipitation of limestone crystals, which began to absorb moisture passing through the capillaries. As moisture evaporates under the influence of heat, it forms blisters. In this case, car paint defects will not occur if you wipe the surface with suede, dry it and use it without lime impurities.

Painting defect “Curl of varnish”

Why does the varnish curl when the surface dries? The explanation lies in the fact that:

1. The paint is applied in a thick layer. Because of this surface layer dries out, but the bottom one continues to remain wet. Each layer should be dried allotted time, before applying a new layer.

2. The varnish did not dry well. Possibly indoors low temperature or high humidity. The varnish is applied too thickly. The thinner does not match the type of varnish.

3. Matte spots appeared on the surface. As a rule, they appear on putty areas where the varnish is absorbed much faster. In order to avoid such a defect, it is necessary to prime the surface before covering it with varnish. Perhaps these are traces of etchant that was poorly removed.

Painting defect “Color change”

Car painting defects also include color changes:

1. Color changed during drying. A common wizard mistake. He did not test the sample when preparing the mixture. Often the varnish begins to darken after the bitch.

2. The components of the mixture differ from each other in quality parameters.

3. The varnish becomes lighter if the drying reflectors were installed at a short distance.

Painting defect “Craters on the paint surface”

Holes appeared on the surface of the paint:

1. The car was placed in a very hot chamber too early after applying the varnish. Lighter solvents began to boil.

2. Heaters were placed prematurely or too close. Pre-drying should be carried out for 15 minutes before placing the part in the drying chamber.

3. Protective covering applied in a very humid environment.

4. Craters on the surface may be caused by polishing using silicates.

5. The car was in a very polluted place for a long time.

Painting defect “Joint at the transition of tones”

Also, one of the common defects is a joint with a gradual transition of tones. Car painting defects of this kind will not occur if you first polish the surface to be painted with sandpaper. After painting the area, the polished surface is painted with a mist spray of the same, but more liquid paint, with the boundaries expanding as each layer is applied. The new painted surface is connected to the transition zone after drying.

Almost the same defect is represented by a “recessed joint”. Only in this case the working area is located in the middle of the panel. The transition area is also polished and painted with a spray gun, varying the paint dilution and distance.

Car painting defects also include softening. This occurs due to the application of a layer of paint on a poorly dried layer. As a result, the solvent of the previous layer softens the surface layer. To correct the situation, it is recommended to repaint the entire part or up to the border, which serves as a visual distinction between the newly painted surface and the old surface.

Painting defect “Haze”

Insufficiently dry air causes car paint defects such as dullness. This problem appears especially often when working with the most sensitive paints, red and blue colors. Poor air drying also leads to the formation of craters on the surface being painted. That is why, in order to avoid the appearance of defects in painting, it is necessary to monitor the wear and tear of the equipment and keep it in impeccable condition.

Sometimes the cause of a defect is the lack of proper service. First of all, we are talking about washing and cleaning. Unmaintained equipment causes craters to form due to water or oils escaping from the compressor; shagreen as a result of an inappropriate paint spray; clogging due to the absorption of dirt from the walls drying chamber.

Painting defects caused by the manufacturer

Quite often, car paint defects occur due to the fault of the manufacturer. The main reason is the difference in viscosity in batches produced at different times. And also, the appearance of oils or water in the paint due to poorly cleaned and dried containers.

Often defects appear due to equipment.

These include, first of all, wear and tear. Including wear and tear of the spray gun, which manifests itself in the following:

The presence of defects on the cover, as a result of which the holes intended for air flow are clogged or deformed.
The end of the needle is damaged and does not close the nozzle correctly, causing paint to drip rather than spray.
A damaged nozzle prevents paint from coming out evenly.

With any of these damages, the paint torch comes out with a change in shape. This equipment defect causes unevenness in the applied film of paint material. The result is the appearance of shagreen, smudges and a matte effect.

Worn compressor. Equipment defects include compressor wear. It manifests itself in the inability to provide sufficient pressure at the outlet of the spray gun. This not only leads to defects, but can also make painting almost impossible.

Lack of conditions for car painting

Defects in car painting will also appear in the absence of the necessary drying and. If the room is not ventilated enough, humidity may increase. And if, in addition, the master floods the floor with water to reduce dust content, the coating may lose its shine.

Due to deformation in the supporting structure of the drying chamber filter, air flows incorrectly. In this case, uncontrolled dust may enter the chamber. Naturally, the appearance of the painted surface will be unsatisfactory.

Incorrect operation of thermometers, pressure gauges and viscometers also lead to the formation of defects. Or they interfere with the timely detection of possible irregularities in work, which subsequently affects the quality of painting. This occurs due to incorrect pressure, temperature and viscosity readings.

For successful work, it is important to prepare the air for spraying. To supply it, it is necessary to provide an appropriate system. The main components are a compressor with a condensed water release valve and pressure gauge, a dryer, oil and water filters and a pressure regulator. If any of the components are missing, defects in the car's paint will appear.

Painting defects due to non-compliance with technological requirements

Failure to follow the prescribed process for using materials is also a reason for unsuccessful painting. This most often occurs when mixing components from different manufacturers. One of the manifestations of such a disorder is wrinkling. When correcting these defects in car painting, it is necessary to remove layers of paint and varnish materials to the layer where wrinkling has not occurred.

A classic example of mistakes made when painting is the use of nitro as a universal thinner. The defects that arise from such illegibility are quite varied, matte effect, boiling, shagreen, wrinkling, etc. To avoid defects, you should use those materials recommended by the manufacturer.

Preparation for painting (surface cleaning)

Before starting work good master Be sure to remove contaminants from the surface of the object being painted. These contaminants can be sanding residues, sanding paper, or water. Wash off salt and oil from your hands.

Before painting, each item must be thoroughly cleaned and dried. Otherwise, some defects in car painting , like the formation of craters, will begin to appear almost immediately. Later, bubbles or cracking of the applied paint layer may appear. Such defects can only be corrected by re-cleaning the surface and repainting.

Cleaning of surfaces and further painting must be carried out in compliance with all conditions to prevent defects in the car’s paintwork. If you try to collect them all together, you will get a fairly small list, which will not be difficult to adhere to.

Cleaning from dirt and rust. The surface must be degreased using cleaning agents and dried. Particular attention is paid to the edges. The cleaned surface should not be touched with hands.
It is necessary to sand the old paint down to the very base.
The temperature in the workroom should not fall below 18°C. The hardness of the water should be as high as possible. After sanding, any remaining water should be thoroughly wiped off.
Keep the compressed air clean and dry.
Secondary primers are applied using a nozzle with a diameter of 1.5-1.8 mm, for top coat enamels - 1.1-1.4 mm.
Drying and painting booths must have dust filters, fresh air supply, and steam exhaust.
It is necessary to re-protect against corrosion all areas that have been subjected to excessive grinding.
Apply the next layer of paint after the previous one has completely dried.
Observe the prescribed operating viscosities.

Let's look at typical problems that can arise in cases where the paints and varnishes, the approach to painting work is carried out, the processes of painting, drying, etc. are disrupted.

(cracking and peeling of the paint layer)

Probable reasons:

the paint is applied in a very thick layer, especially if alkyd or oil paint was used;

was applied in unsuitable weather conditions - in extreme heat, when upper layer paint dries faster than the base layer;

painting was carried out in a damp room;

Uncleaned surface is painted.

Solution:

Remove loose paint with a wire brush and sand. If using primer paint, allow it to dry completely. For repainting, use high quality paint.

(deep, irregular cracks that resemble a dirt-covered surface)

Probable reasons:

the paint is applied too thickly, usually on a porous surface;

the paint is applied too thickly to a surface previously painted with lower quality paint to improve the coating;

paint has accumulated in the corners without being leveled.

Solution:

Delete old layer paint scraper or sandpaper. Clean the surface, then prime and repaint. Using high quality latex paint can prevent cracking because this paint forms a more elastic film compared to water-based paints.

(traces of uneven texture on the painted surface)

Probable reasons:

the wrong type of roller was used;

the wrong technique was used when painting with a roller.

Solution:

Make sure to choose the right type of roller. If the roller has been washed before, make sure that the water has been squeezed out of it. Do not allow paint to pool around the edges of the roller. Start working from the ceiling and continue down in small areas. Apply paint using the M or W technique, starting from the top and without lifting the roller from the surface.

(the paint film cracks due to aging, which leads to peeling of the paint layer)

Probable reasons:

low quality paint was used, which does not provide tight adhesion to the surface and is not elastic;

the paint is applied in too thin or thick a layer;

improper surface preparation or applying paint to a wooden surface that has not been treated with primer paint;

cracks resulting from deformation of the painted surface;

seams and surface cracks are processed technologically incorrectly.

Solution:

Remove loose paint with a scraper or wire brush, sand with sandpaper. If necessary, putty. Before painting, the surface must be primed.

When painting a wooden surface, first prime, then putty (acrylic putty). When repairing a wall or ceiling, putty first, then primer.

(differences in tones of a surface painted with the same paint)

Probable reasons:

a defect usually observed when the surface was painted with a roller and the corners with a brush. A brush-painted surface is usually darker than a roller-painted surface. Spray painted surfaces are usually different from roller or brush painted surfaces.

adding pigment to non-tinted paint or incorrect dose of pigment.

Solution:

Ensure uniform coverage when using different painting tools. Paint smaller surface areas to keep the paint wet at all times. When purchasing tinted paint in a store, it is recommended to mix the paint in the container before use.

(uneven absorption of paint by the surface)

Probable reasons:

When painting, no water was squeezed out of the roller;

low quality, low density paint was used;

poured wall, ceiling;

the paint was applied in different directions;

the surface was not primed before painting;

variable drying temperature.

Solution:

Before painting, be sure to prime the surface.

Particular attention should be paid window openings, doors and corners where this problem may appear. Using high-quality paint with a high content of pigments and binders will make the joints less noticeable.

When using alkyd paint, this problem occurs less frequently.

(in some places there is no adhesion of the paint to the surface, the paint film lags behind the surface, forming a bulge)

Probable reasons:

oil or alkyd paint applied to wet surface;

moisture penetration through outer wall;

incorrect application technique was used;

tools not suitable for their intended purpose were used for application.

Solution:

At the site of swelling, the surface is sanded, re-treated with appropriate putty, sanded again and repainted with high-quality paint.

If the entire surface is damaged down to the base, it is necessary to eliminate the source of moisture (if possible), then clean, prime and repaint the surface.

(the paint turns yellow over time)

Probable reasons:

alkyd oxidation, oil paint or varnish;

exposure to heat (stoves, radiators, stoves);

exposure to darkness (behind paintings, furniture, equipment, in closets, etc.);

Excessively diluted paint was used.

Solution:

High-quality paints do not yellow over time. Alkyd paint has this property, especially in places inaccessible to sunlight.

(when drying, the paint forms a non-uniform, uneven surface, leaving visible roller marks)

Probable reasons:

the surface is not properly prepared for painting (degreased, sanded);

an attempt to repaint a newly painted surface with the same paint;

low quality paint used;

an attempt to touch up an almost dry surface;

using the wrong type of roller or poor quality brush;

incorrect painting conditions ( low humidity air and high temperature).

Solution:

Use high quality water-based paint with good self-leveling ability. When using a roller, make sure you choose the right one (the length of the pile and the material of the roller are important). It is important to use high-quality brushes - the lower the quality, the worse the brush picks up and evens out the paint.

(low paint resistance to various loads (friction, scratching))

Probable reasons:

matte paint was used in rooms with high loads, where paint with a higher level would be more suitable high degree shine;

frequent washing and cleansing stains;

contact of objects (furniture) with a painted surface;

paint with low wear resistance was used.

Solution:

It is necessary to choose a paint that is highly wear-resistant and easy to maintain. In high-traffic areas, semi-shiny or shiny paint is preferable, but not matte. It is recommended to clean the surface soft material and rinse clean water. The paint must be allowed to dry thoroughly (wash after a week).

(black, gray or brown spots appear on the surface)

Probable reasons:

usually appears in damp rooms where there is no ventilation or little daylight (bathrooms, kitchens);

oil-based or alkyd or low-quality water-based paint was used;

before painting wooden surface has not been primed or processed;

a moldy surface was repainted without cleaning.

Solution:

To prevent mold, the surface should be treated special means to remove mold, and use a durable water-based paint that can withstand cleaning with bleach or detergents. Consider the possibility of ventilation of the room.

(when the dried paint does not completely cover the surface)

Probable reasons:

low quality paint used;

the wrong type of roller or low quality brush was used;

poor paint leveling ability or lack of pigments;

when using much lighter paint, applying it too quickly against the background of darker paint.

Solution:

Make sure the alignment is consistent when using different painting tools. Paint smaller surface areas to keep the paint wet at all times. When purchasing tinted paint in a store, it is recommended to mix the paint in the container before use.

If the surface is darker than the selected paint tone or the selected wallpaper pattern is tinted, then the surface should be primed before painting. It is recommended to use high quality paints with high coverage and leveling properties. Use the proper tools. To be on the safe side, always prime the surface.

(the appearance of pores on a paint layer when bubbles burst while the paint dries)

Probable reasons:

very low-quality or old water-based paint was used;

After painting the car, numerous outlines of intact and burst bubbles appeared on the body.

What will happen next?

In places where a defect occurs, the decorative coating of the car will quickly wear out. Cracks and rust will appear in place of the bubbles.

Why did this happen?	What should I have done?
A thinner was used during the preparation of the coloring agent. Bad quality, which spoiled the technical characteristics of the finished mixture.	To prepare any car paint, use only proven components. Be sure to make sure that all products have a normal expiration date, use only those samples that the manufacturer recommends in the instructions.
A “high-speed” thinner was added to the paint, which caused too violent chemical reaction ready mixture. This led to the appearance of bubbles on the surface finished coating car.	All components of a complex coloring agent must be selected with pinpoint precision. Do not experiment and add only “native” additives recommended by the manufacturer. They are chosen taking into account technical characteristics working room.
The spray gun was poorly adjusted during operation. For this coloring agent we chose too high pressure air supply, the gun nozzle also significantly exceeded the recommended value.	All necessary parameters of the paint gun are indicated in the paint manufacturer’s instructions or in the car painter’s work instructions. Follow these recommendations exactly and do not exceed the values indicated in the table.
The car body coating system was applied incorrectly: the thickness of the finishing layers was increased, and temporary pauses between their application were not maintained.	All finishing layers of the vehicle coating system must be of the proper thickness. Acceptable parameters must be specified in the instructions of the manufacturer of the coloring agent. Properly pause between each coat of finish.
They decided to dry the freshly painted surface of the car using the heating method. Because of this, the fragile “armor” bulged, forming bubbles on its surface.	Don’t force things and don’t try to speed up the drying time. automotive coating. This can only be done after the top finishing layer of the system has been sufficiently secured.
A freshly painted car is in a very hot environment. The air temperature is unfavorable for normal drying of the coating system; “extra” degrees cause the paint to boil.	The vehicle drying room must be adjusted to the ideal parameters for the “calm” hardening of the specific product used. All recommendations for this stage of repair are specified in the manufacturer's instructions.
We decided to speed up the drying of a freshly painted car coating using infrared heaters. They were turned on too early or placed too close to the car.	An infrared heater is used to speed up the drying of a car's coating. But to install it, the right place must be chosen (not too close to the car!), and “help” must be turned on only after the top layer of paint has been sufficiently fixed.

What should I do to fix the defect? This disadvantage requires urgent correction. A bubble’s breakthrough is dangerous for the “health” of the car’s coating, so clean out all the formed craters on its surface with an abrasive material. Then the car body is carefully prepared and repainted.

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