Painting of body parts of the car: from preparation to polishing

Crushing, scratching or fading paintwork – problems faced by every owner motor-car over time. Aggressive environment, reagents on the roads and mechanical impacts leave their mark on the body, requiring immediate intervention to prevent corrosion. Quality paint-painting Not only does it restore the aesthetic appeal of the machine, but it also protects the metal from destruction.

The color restoration process can range from locally repairing an individual element to completely repainting the body. The choice of method depends on the degree of damage, the type of paint and the financial capabilities of the owner. In this article, we will analyze in detail all the stages of work, the necessary tools and subtleties of technology that allow you to achieve a result indistinguishable from the factory coating.

Many motorists are wondering: is it worth taking up the task yourself or entrusting the task to professionals? The answer lies in the availability of experience, equipment and a willingness to observe strict technological discipline. Even a small area requires careful preparation, otherwise the new paint will quickly begin to peel off or change the shade.

Diagnosis of damage and choice of repair method

The first step is always to inspect the surface thoroughly. It is necessary to determine the depth of damage: whether only the varnish is affected, whether the scratch reached the base layer of the paint or the metal and soil itself are damaged. Surface defects are often eliminated by polishing, while deep chips require a full-fledged polishing. localization.

It is important to estimate the area of work. If less than 30% of the element is damaged, it makes sense to consider spot repair. However, in case of multiple defects or the presence of corrosion in large areas, it is more advisable to repaint the entire part. This ensures uniformity of color and no visible transitions.

Particular attention should be paid to the identification of hidden problems. Sometimes under the externally small chip hides a rust focus, which continues to grow under a layer of paint.

⚠️ Warning: If you feel roughness or bloating of paint when you feel your finger through a napkin, this is a sure sign of corrosion that has begun. A simple paint here will not help - you will need a strip to the metal.

For accurate color selection, you need to know the paint code of your car, which is usually indicated on the plate in the doorway or under the hood. However, even knowing the code, it is worth considering the natural fading of the body over time, so colorists often do it. computer-selection depending on the age of the car.

Required tools and materials for the job

The quality of the final result depends on the equipment and consumables used. Saving on materials in this case is unacceptable, as cheap components can lead to defects, the elimination of which will cost more. The basic set includes grinding machines, spray gun, compressor and personal protective equipment.

The key element is the spray gun. To work with automotive enamels and varnishes, the system devices are best suited HVLP High Volume Low Pressure (HVL) which ensure high material transport and minimize fog formation. The diameter of the duse is selected depending on the viscosity of the paint used, usually 1.3-1.4 mm for the base and 1.5-1.7 mm for the varnish.

The list of required materials is as follows:

• 🎨 Degreasing and antisilicone for surface preparation.
• 🛡️ Soil filler and epoxy soil for metal protection.
• 🌫️ Basic enamel (acrylic or metallic) and car lacquer.
• 📏 Abrasive materials (paper of P80–P2500 gradations)
• 🧤 Respirator, gloves and paint suit for safety.

Do not forget about consumables: paint scotch, covering film, napkins and filters for paint. The use of high-quality filters in the spray gun will prevent debris from getting into the spray torch, which will exclude the formation of craters and “garbage” on the fresh coating.

Technology of surface preparation for staining

Preparation takes up to 80% of the time of all work and is the foundation of a quality result. First, the detail is thoroughly washed and degreased. Then, mechanical cleaning of the damaged areas is performed. If there is corrosion, the metal is cleaned to shine, often using a rust converter.

Then the soil is applied. On bare metal, first, epoxy soil is placed for anticorrosion protection, then an acrylic filler, which hides the risks from sandpaper and levelles the surface. After drying, the soil is grinded with abrasive P400–P500 enamel P600–P800 metallic.

It is important to follow the wet-wet or interlayer drying rule specified by the material manufacturer. Violation of time intervals can cause the solvent from the bottom layer to begin to come out later, causing the paint to boil or loss of adhesion.

The final stage of preparation is compressed air blowing and re-degreasing immediately before painting. Any dust left on the surface will become a noticeable defect after applying the varnish.

Painting process

Painting is carried out in a specially equipped room - a paint chamber or a clean, dust-free garage with good ventilation. The air temperature should be within 20-25 ° C, and the humidity should not exceed 70%. Violation of these parameters can lead to matteness, shaking or clouding of the varnish.

The technology of application depends on the type of paint. Basic enamels (metallic, mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of father of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of mother of child of child of child of child of child of child of child of child of child of child of child of child of child of child of child of child The first layer is made thin, "dusty" to provide adhesion. The subsequent layers are applied more saturatedly, but without the formation of flows. It is important to keep the gun perpendicular to the surface at a distance of 15-20 cm.

After drying the base (usually 20-30 minutes), varnish is applied. Lacquer protects color from ultraviolet light and gives depth. It is applied in 2 layers: the first is a thin binder, the second is wet, glossy. The second layer forms the final look of the part.

⚠️ Warning: Never try to apply a thick layer of paint or varnish “in one aisle” at once. This is guaranteed to lead to leaks that will take a long time and are difficult to eliminate by grinding.

For complex colors such as three-layered mother of mother-of-pearl or complex metallics, the technology may involve applying an additional intermediate layer or a special fog layer to exhibit the effect.

Table of selection of abrasives and materials

The correct selection of grinding materials grain is critical for adhesion and appearance. Below is a reference table that helps you navigate in the gradations of abrasives for various stages of work.

Work phase	Materials	Recommended gradation (P)	Purpose of use
Rust cleaning	Pearl / Circle	P60 – P80	Rough removal of corrosion and old paint
Grinding the putty	bacon	P120 – P180	Levelling of the repair spot
Preparation of soil	Pandea/Grid	P240 – P320	Primary filler alignment
Finished under base	bacon	P400 – P500	Creating risks for enamel adhesion
Polishing the polish	The polishing circle	P1500 – P3000	Removal of shaking and glossing

Using too rough abrasive before painting can cause the risks to manifest through the paint after shrinking. Therefore, the transition to a smaller grain before applying the finishing layers is mandatory.

Drying, polishing and elimination of defects

After applying the varnish, it takes time for polymerization. Although the surface may appear dry after an hour, full hardness is gained over a period of days or even weeks, depending on the type of hardener. Accelerated drying with infrared lamps is possible, but requires caution not to boil the material.

After complete drying, polishing is often required, especially if the staining was not carried out in ideal conditions and dust settled on the varnish or a shaking was formed. Polishing is performed in several stages: first, defects are removed with abrasive pastes, then the finishing paste restores shine.

What should I do if a leak appears?

If the lacquer flow is detected immediately, it can be carefully removed by getting wet with a soft napkin, but not rubbing. If the varnish is already grasped, you must allow it to dry completely (12-24 hours), then gently grind the bulge with the abrasive P1000-P1500 and polish the repair site. Haste will lead to smearing of the varnish and spoilage of the entire element.

In the process of polishing, it is important not to overheat the varnish, working at low revs of the polishing machine and constantly monitoring the surface temperature with your hand. Overheating can lead to clouding or even rubbing the varnish to the base, which will require repainting.

Cost of work and feasibility of self-repair

Financial issues often become crucial. Professional painting of one part in a specialized center can cost from 5 to 15 thousand rubles and more, depending on the class of the car and the complexity of the color. Self-repair requires the purchase of equipment (compressor, spray gun, grinder), the cost of which can pay off only with regular work.

However, if we consider a one-time repair, the purchase of materials for independent work (soil, paint, varnish, solvents, abrasives) can be 30-50% of the cost of service. The risk of making a mistake and repainting the part again remains high.

It is advisable to take up the case yourself if:

• 🔧 You plan to repair your cars regularly.
• 🚗 Damaged part, the cost of painting which in the service exceeds the market value of the part itself (for example, old plastic bumpers).
• 💡 You want to gain experience and are willing to spend time learning and experimenting.

In cases where the car is under warranty or damage complex (hit body geometry), it is better to contact professionals. This will keep the vehicle liquid and guarantee quality.

How much dried car paint before polishing?

The drying time depends on the temperature and type of materials. At +20 ° C, acrylic enamel dries for about 24 hours, varnishes - from 12 to 24 hours. You can polish only after complete polymerization, otherwise the abrasive will clog and the varnish will become cloudy.

Do I need to take out a detail for painting?

Ideally, yes. The removed part is easier to prepare qualitatively, paint the ends and avoid getting paint on neighboring elements. However, experienced craftsmen make high-quality local repairs without removal, using careful masking.

Can I paint my car in the winter in an unheated garage?

It's not recommended. The low temperature slows or stops the chemical reaction of hardening, the paint may not dry, become coated with matte or peel off. The minimum temperature for most materials is +15°C.

What is a transition in painting?

Transition (or stub) is a technology of local repair, in which the new paint smoothly passes into the old with the help of a special solvent. This avoids the visible border and repainting the whole detail.