Self-painting is a challenge that many motorists who want to save on professional services or just enjoy the process of transforming their car throw themselves. However, before opening a jar with enamel, you need to soberly assess your strengths and capabilities, because paint-painting It requires not only a flat hand, but also a strict temperature regime and sterile cleanliness. Errors at the preparation stage can negate all efforts, turning the body into an uneven surface with bubbles and leaks, so the theoretical basis here is critical.
The process of restoring paint coating (LCP) is divided into several key stages: dismantling of attachments, cleaning of rust, putty, priming and final application of enamel with varnish. Acrylic enamel Metallics and metallics require a different approach, and the choice between a single-stage and two-stage coloring system depends on the desired result and budget. In this article we will discuss the fundamental principles without which long-term protection of the body from corrosion is impossible.
It is worth noting immediately that perfect factory smoothness (the effect of “orange peel” is absent) in garage conditions is achieved extremely rarelyAnd you have to be prepared psychologically. Nevertheless, a competent approach allows you to get a result that will be visually indistinguishable from the factory at arm’s length, reliably protecting the metal from an aggressive external environment.
Organization of workspace and choice of materials
The first thing that a master amateur faces is the search for a suitable room. Dust is the painter’s main enemy, settling on fresh paint and creating ineradicable defects. The ideal option is a specialized paint camera, but in the realities of garage repairs you have to be content with a carefully cleaned workshop or even a canopy in the yard in dry weather. It is important to ensure the absence of drafts that can disrupt the drying process of solvents and lead to turbidity of the varnish.
Lighting is no less important than cleanliness. You will need a powerful light source with a color temperature close to daylight to properly assess the shade of paint and see small irregularities. Using halogen spotlights can distort colors, so LED lighting A high color reproduction index is preferable for quality control.
The choice of materials determines the final result. Modern LCP repair systems are usually based on acrylic products. You will need to purchase a filler soil, base enamel (if it is metallic or mother of pearl) and acrylic varnish. Don't skimp on it. solvent and hardeners: using cheap analogues can lead to the fact that the paint will not stand up, go bubbles or change color over time.
Buy all components (soil, paint, varnish, solvent) from one manufacturer to avoid chemical conflict of materials and ensure predictable results.
Dismantling and primary body preparation
Quality painting is impossible without full or partial dismantling of the hinged elements: handles, moldings, headlights, bumpers and mirrors. An attempt to paint parts “in the collection” or to seal them with paint tape almost always leads to visible transition boundaries and accumulation of moisture under the edges. In addition, access to complex geometric shapes without removing elements is limited, which is fraught with neprocrastins.
The next stage is washing the body using a degreasing agent. All traces of bitumen, silicone, oil and road dirt must be removed. Pay special attention to the joints of the panels and hidden cavities where chemistry can accumulate. After washing, the body is thoroughly dried, since the moisture under the paint layer will cause corrosion and bloating of the coating.
Mechanical cleaning is carried out with abrasive materials. Deep corrosion foci and old swollen coating are removed to pure metal. For this purpose, grinding machines with circles of different grains or sandpaper are used. Transition boundaries between the cleaned metal and the old varnish should be as smooth as possible to avoid steps after painting.
☑️ Initial body preparation
Recovery of geometry: spatula and grinding
After cleaning the rust, dents and irregularities are often found that require alignment. For this purpose, a car putty is used. It is important to apply the material in thin layers, allowing each previous layer to be completely polymerized. The thick layer of the putty can crack or peel off during operation due to the difference in the coefficients of temperature expansion of the metal and polymer.
Grinding the putty is the most time-consuming process. The method of “development” is used: a developing powder is sprayed on the surface (or a marker is used), after which grinding is performed. Where the development disappears most quickly, there are depressions where you need to add more material. This cycle is repeated until a perfectly flat surface is reached.
⚠️ Warning: Never apply a putty on bare metal without pre-treatment with phosphate soil, if recommended by the material manufacturer, otherwise moisture can be preserved under the layer of putty and hidden corrosion begins.
For finishing grinding under the ground, an abrasive with a gradation P180–P240 is used. Larger grains will leave a risk that the soil will not cover, and too small (below P320) can lead to poor soil adhesion. The surface should be matte and uniform throughout the repair area.
Printing: the basis of adhesion and protection
The soil performs two functions: provides adhesion (clutch) of paint with metal or putty and fills in the small risks from grinding. There are several types of soils: acid (phosphate), epoxy and acrylic fillers. Acids are applied first layer on bare metal to passivate corrosion, epoxy creates a powerful waterproofing film, and acrylics serve as the main leveling layer.
The technology of soil application requires the presence of a spray gun with a properly selected duse (usually 1.6-1.8 mm). The soil is applied in 2-3 layers with interlayer drying, indicated in the technical map of the product. It is important not to overdry the soil, but also not to apply the next layer to the “raw” previous one to avoid boiling the solvent.
| Type of soil | Appointment | Drying time (20°C) | Compatibility |
|---|---|---|---|
| Acid (phosphate) | Anti-corrosion protection of bare metal | 15-30 minutes | Requires overlapping with acrylic soil |
| epoxy | Waterproofing, adhesion | 12:24 hours. | It can be the basis for a putty or paint |
| Acrylic filler | Alignment of the risks, the basis for the paint | 30-60 min (before grinding) | Universal for most enamels |
| Plastic soil | Adhesion to bumpers and linings | 10-15 minutes | Only for polypropylene parts |
After drying, the acrylic soil is grinded with an abrasive P400-P600 under enamel or P800-P1000 under metallic. The surface should be smooth as glass, without a single scratch. Any risk left at this stage will manifest through the paint layer, especially if dark color or metallic is used.
The Secret of Perfect Ground
Use “wet grinding” with water to finish the soil treatment if you are a beginner. This allows you to see the real surface relief, as water fills the micro-scratch, making them visible. However, make sure that the soil is completely dry before applying the paint, otherwise moisture will provoke defects.
Technology of application of basic enamel
Applying the basic enamel (color) is the most responsible and creative stage. If you work with metallic or mother of pearl, the paint consists of two components: base (pigment with aluminum powder) and varnish. Basic enamel is applied in thin "fog" layers. The first layer (wet) sets the tone, the second and third (dryer) distribute the metal and align the hue.
It is critically important to observe the interlayer drying time, which is usually 10-15 minutes at a temperature of 20 ° C. If you do not allow the solvent to come out, when applying the varnish, boiling or clouding may begin. A gun. You need to keep perpendicular to the surface at a distance of 15-20 cm, moving at a uniform speed. The overlapping of the strips should be 50%.
When working with complex colors (e.g., three-layer mother of pearl or “chameleon”), the technology may require a base in two stages with intermediate varnishing or the use of special binders. In such cases, the instruction from the paint manufacturer is law and cannot be derogated from.
The uniformity of the distribution of metal powder depends on the viscosity of the paint, the pressure at the exit of the torch and the speed of the hand - train on test plates before going to the body.
Lacquering and finishing
Lacquer is a protective layer that gives depth to the color and glossy shine. It is placed on top of a fully dried (matted) base. Usually used two-component acrylic varnish with hardener. It is important to prepare the mixture exactly in proportion, otherwise the varnish may not dry or become too brittle.
Lacquer is applied in 2-3 layers. The first layer is thin, binding. The second layer is wet, glossy, which forms the final surface. A third layer may be required to eliminate minor defects or on large planes. The main rule: do not overdo it to avoid leaks. If the leak is still formed, it can be carefully removed after complete polymerization of the varnish (after 24 hours) with a blade or abrasive, and then polished.
After the varnish has dried (complete polymerization takes days to weeks), the surface often has a fine shavern ("orange peel"). To achieve mirror shine, polishing is used. Abrasive pastes of varying degrees of grain and a polishing machine with circles of sheepskin or pore are used.
⚠️ Warning: Start polishing no earlier than 24 hours after painting, and it is better to wait a few days, as the polish should gain hardness, otherwise you will simply smear it or rub it to the base.
Frequently Asked Questions (FAQ)
Can I paint my car at high humidity?
It's not recommended. High humidity leads to condensation of moisture on the surface of the metal and in the spray torch, which causes the matteness of the varnish (blushing plaque) and loss of adhesion. The ideal humidity for painting is 40-60%.
How much dried car paint in the garage?
The drying time per stick is 30-60 minutes, but full polymerization (strength set) takes 7 to 30 days depending on the temperature and type of materials. Washing the car with abrasives can not be earlier than a month.
Do I need to remove the old paint completely?
Not if the old coating is held firmly, has no swelling and corrosion. It is enough to wrap it with an abrasive P800-P1000 to create an adhesion and degrease. Complete removal is required only in the presence of serious defects.
What compressor is needed to paint a car?
Amateur painting requires a compressor with a capacity of at least 300-350 liters per minute and a receiver of 50 liters to ensure stable pressure without pulsation, otherwise the torch will “spit” the paint.
What to do if the paint goes bubbles?
Bubbles (boiling) occur due to rapid drying of the surface, trapping the solvent inside, or applying a too thick layer. The defect must be completely sanded to a healthy layer, dry and repaint the area again, observing interlayer drying.