Direct operation of a vehicle with applied but unpainted ground It is possible only as a short-term measure, since most repair compounds are not designed for prolonged exposure to ultraviolet light and moisture. The open layer of epoxy or acid primer begins to break down under the sun's rays after a few weeks, losing its adhesive properties and letting moisture into the metal. Owners often ignore this fact, believing that since the metal is covered with a gray or yellow layer, the metal is not covered with a yellow layer. corrosion They are not threatened, but the chemical structure of such materials requires mandatory finishing insulation with varnish or enamel.
If you plan to leave your car in this condition for a season or more, you should understand that acidic soil (wash primer) can not be used as a finishing coating at all because of its hygroscopic nature. They actively absorb atmospheric moisture, which leads to swelling and peeling of the entire repair site. Even more persistent epoxy compounds with excellent anticorrosion protection, over time shallow and burn out, ceasing to perform the function of a barrier to oxygen.
Long-term absence of paint on the body inevitably leads to local foci of rust, especially in places of chipping or poor surface preparation before priming. The critical factor is not only the type of soil, but also the storage conditions of the car.Since garage content can prolong the life of such a coating, but will not save it from degradation completely. Below we will discuss in detail the technical nuances, types of materials and the real terms of safe operation.
Chemical properties of road soils
The fundamental difference between soil types determines their ability to resist the external environment without additional coating. Acid soilsOrthophosphoric acids are designed to chemically bind to metal and neutralize residual corrosion, but they are extremely sensitive to atmospheric influences. Their porous structure requires mandatory overlapping with filler, since they do not create a sealed film necessary for protection from water.
Epoxy soils They form a dense, non-porous film that physically blocks the access of oxygen and moisture to the body. This type of material is the closest to the possibility of temporary operation without paint, as it is chemically inert and has high mechanical strength. However, even epoxy is subject to photo-oxidation: under the influence of UV radiation, the polymer chains are destroyed, the surface becomes matte, rough and begins to pass moisture.
There are also fillerThese are often used as an intermediate layer. They have good filling capacity, but high hygroscopicity. The water is then then stained with water, and the water is then swelled with the sun and then the water is swelled. Therefore, the use of such materials as a finish is strictly not recommended.
⚠️ Warning: Never use acid soil as your only protective layer. It requires mandatory overlap with acrylic or epoxy material, otherwise corrosion will begin under the soil layer after 2-3 weeks of active operation.
To understand the resistance of different types of coatings, it is worth considering their main characteristics in comparison:
| Type of soil | Resistance to UV | Wet resistance | No paint term |
|---|---|---|---|
| Acid (Wash Primer) | Low. | Low. | Not recommended |
| Epoxy (Epoxy) | Medium | Tall. | Up to 6 months. |
| Acrylic filler | Low. | Medium | 1-2 months |
| Sound enamel (1K) | Medium | Medium | Up to 1 year |
Double-layer technology
Why is one layer of soil worse than two? Applying the soil into two thin layers with interlayer drying creates a more uniform polymer mesh, which significantly increases the barrier properties of the coating compared to a single thick layer that may not dry inside.
Environmental Impact on Open Grounds
The aggressiveness of the external environment is the main cause of unprotected paint coating or its substitutes. Ultraviolet radiation starts the process of destruction of polymers that are part of the soil. Visually, this manifests itself in a change in color (yellowing or burning into white chalk) and loss of gloss. The surface becomes porous, making it easier for water and saline solutions used by utilities in winter to penetrate.
Humidity and temperature changes create the effect of "breathing" the body. When heated, the air in the soil pores expands, when cooled, it shrinks, drawing in microscopic drops of water with dissolved reagents. Cyclical freezing and thawing This moisture leads to microcracks, which over time grow and reach the metal, triggering the rusting process under the layer of protection.
The mechanical effects of sand and fine road dust also play the role of abrasive. Open ground, especially acrylic, softer (softer) paint. When moving along the highway, the airflow with dust particles gradually grinds the surface, thinning the protective layer. In the zones of direct impact of stones (front edges of the hood, wings), the soil is chipped much easier than a full-fledged system of "ground-paint-varnish".
- 🌧️ Rainwater with acidic impurities accelerates the chemical destruction of binders in the soil.
- ☀️ Direct sunlight causes rapid pigment burnout and destruction of the polymer structure.
- ❄️ Road reagents (salts) penetrate the micropores and cause electrochemical corrosion of the metal.
- 🍂 Organic (bird droppings, tree juice) is eaten into the porous structure of the soil deeper than in smooth paint.
The main enemy of the soil is not water itself, but cycles of drying and wetting combined with ultraviolet light, which turn the protective film into a sieve.
Safe operation without painting
The time period during which you can ride on a primed car depends on the type of material used and operating conditions. For epoxy In a temperate climate and garage storage, this period can reach 6-12 months without visible signs of degradation. However, with a year-round street parking, this period is reduced to 2-3 months.
Acrylic filler soils They begin to lose their properties much faster. In summer, the active sun is able to "burn" the upper layer of such soil in 3-4 weeks, after which it will be impossible to wash it off with water - mechanical cleaning will be required. In winter, under the influence of reagents, acrylic can begin to bubble after a month of operation.
There is a compromise option – the use of squirrel (often labeled as 1K soil). These are single-component compounds that contain more pigment and protective additives than conventional soils. They can serve as a temporary coating for up to a year, but their color range is limited, and the resistance to shine and depth of color is still inferior to full-fledged automotive enamel with varnish.
It is important to consider that even if the soil looks whole, its adhesion to the metal can be broken. Attempting to paint a car after a long period of downtime in this state often leads to the fact that new paint falls on the weakened (bottom layer) and soon falls off with it. Therefore, before painting after a long pause, it is recommended to lightly rub the surface with an abrasive.
⚠️ Warning: If you find white salt swellings or swellings on primed parts after winter, painting over them is prohibited. It is necessary to completely remove the defective soil to the metal and repeat the preparation cycle.
Technical risks and problems with the body
The main risk of operating a car without the finishing layer of paint is the hidden development of corrosion. Unlike painted surfaces, where rust often acts as bloating ("redheads"), on the ground the process can go hidden, especially if a porous material was used. Film corrosion It corrodes the metal, and when the defect becomes noticeable, the metal loss can already be critical.
Another problem is the difficulty of painting. If the soil has been under the open sky for a long time, it is contaminated with oils, silicones and atmospheric dust, which penetrate deeply into the structure. Degreasing the surface may not work, leading to craters or detachments after the finishing enamel is applied. paint adhesion The “old” soil is always lower than the fresh one.
It is also worth mentioning the loss of presentation and the difficulty of color selection in the future. Burnt soil is difficult to assess for the quality of preparation: you can not see the drawings from grinding, pits and irregularities. This can lead to defects that had to be eliminated during the priming stage, but they were hidden by a layer of dust and burnt-out material.
- 📉 Reduction of the residual cost of the car due to unkempt appearance and questions to the condition of the body.
- 🔨 The risk of peeling off future paint due to a violation of adhesion to (old) soil.
- 👁️ Inability to assess the level of the surface before the final painting.
- 🧪 Chemical incompatibility: Some paints can react with aged soil.
Tip: If you have to ride on the ground for a long time, regularly (once a month) apply a layer of liquid wax or special silant to the surface. This will create a temporary hydrophobic layer and prolong the life of the coating.
Interim solutions and alternatives
If a full-fledged painting is not currently possible financially or technically, there are ways to minimize damage to the body. The easiest and most affordable method is the use of spray-enamel in the tone of the soil or universal colors (black, white, gray). They will not give a perfect hit in color, but will create the necessary sealed layer that protects against UV and moisture.
Another option is to paste the parts with vinyl film. The film completely blocks the access of air and light to the ground, allowing the car to be operated for years without changing for the worse. However, this method requires a perfectly flat surface, otherwise the film will repeat all the defects of the grinding and dimple, making them even more noticeable.
To protect the ends of doors, sills and arches can be used rubber or special anti-gravel compounds. They create a thick, elastic layer that is not afraid of rocks and salt. This solution looks rough, but functionally protects the most vulnerable parts of the body from through corrosion for a long period.
☑️ Checklist of preparation for winter on the ground
Do not forget about regular care. Washing of such a car should be more frequent to remove aggressive reagents. The use of contact wash with brushes is prohibited - soft soil is easily scratched, and dirt instantly gets into these scratches. Just a contactless wash and a soft sponge.
⚠️ Warning: Do not try to paint the primed parts with ordinary nitro-enamell or paints for household use. They do not have the necessary elasticity and temperature resistance, crack quickly and can enter into a chemical reaction with the car soil.
FAQ: Frequently Asked Questions
Can open ground be polished?
Pollinating the soil is not recommended. The polishing is designed for hard lacquer surfaces. Soil, especially acrylic, is too soft and porous. Abrasive paste will simply clog the pores, and heating from the polishing machine can lead to melting or damage to the thin layer. To make the soil smooth, you need to properly grind sandpaper with a P800-P1000 gradation before painting.
How long does the soil dry before operation?
The time of complete polymerization (drying) of the soil depends on the type. Epoxy soils gain full strength from 7 to 14 days, although you can operate the car after 24 hours. Acrylic fillers dry faster - 4-6 hours before "low tide", but complete chemical resistance is acquired in a week. In the first days, it is better to avoid sinks and getting gasoline on parts.
Do I need to clean the ground if it has been standing for a year?
Yes, I will. Over the year, an oxide layer and pollution formed on the surface. Before painting, you must pass the surface with abrasive P320-P400 to remove the oxidized layer and ensure the adhesion of the new paint. If this is not done, there is a high risk of detachment of the finishing surface.
Will the soil protect against rust in winter?
Only temporarily and provided that it is epoxy soil without damage. Acrylic soil in winter is almost powerless against road salts. In any case, the absence of a lacquer layer makes the body vulnerable, and the risk of corrosion in winter increases many times over.
Can I apply the varnish directly to the old ground?
You can apply varnish on the ground without a base (paint), but it makes sense only to create a transparent protective layer on black or gray soil. However, varnish applied to old, aged soil can become cloudy or cracked due to different elasticity of materials. It is better to use soil enamel or full-fledged painting.