Wheel arches are the most vulnerable area of the body of any car, which is under constant aiming fire of aggressive reagents, sand and stones. Exactly right here. corrosion It starts first, often going unnoticed by the owner until the holes appear. In winter, the situation is aggravated by a mixture of snow and salts, which, stuck in hidden cavities, slowly but surely destroys the metal from the inside.
Timely corrosion-proofing It is capable of extending the life of the body for decades, preserving not only the presentation, but also the structural integrity of the vehicle. There are many ways of protection: from factory underwings to complex polymer compositions that require professional application. The choice of method depends on the operating conditions of the car and the owner's budget.
In this article, we will discuss in detail how to better handle the arches, what materials really work, and which are a waste of time. You will learn about the nuances of surface preparation, without which even the most expensive composition will not give results.
Why Arches Rust First: The Physics of the Process
The mechanism of metal destruction in the area of wheel arches is due to a combination of several factors, the main of which is the abrasive effect. Sand and small rubble, flying out from under the wheels, act as a sandblaster, gradually stripping off the factory layer of paint and soil. The exposed metal reacts instantly with moisture and oxygen.
The second critical factor is road reagents. Chlorides and other chemical compounds used by utilities to combat ice form an aggressive electrolyte with water. This solution accumulates in the niches of the arches, where there is no natural ventilation for rapid drying. Zinc coatingIf it was originally present on the metal, it is consumed more quickly under such conditions.
The situation is aggravated by constructive features. In many car models, arches have complex shapes with pockets and hidden cavities. There is constantly stuck dirt, creating ideal conditions for development. film-corrosion. Rust begins to bubble under the paint, and when the wearer notices a problem, the process is often irreversible without serious intervention.
It is important to understand that even a new car that has just left the cabin is not immune to this scourge. Factory protection is often minimal, especially at the bottom of the sills and arches. The issue of additional protection is therefore a matter for every responsible owner.
Overview of materials: from bitumen to liquid plastic
The antique market offers a wide range of solutions, each with its own advantages and disadvantages. Traditionally, arches were used to protect the bitumen. They create a thick, elastic layer that extinguishes the impacts of stones well. However, bitumen is prone to drying and cracking over time, after which moisture penetrates under the coating, causing active rotting of the metal.
More modern are rubber and rubber-based formulations, often referred to as “liquid under-plates”. They form a strong, sound-proof film. Polyurethane Epoxy compounds are considered the premium segment. They create an incredibly durable coating that is resistant to mechanical damage, but their application requires strict adherence to technology and often professional equipment.
It is worth mentioning separately. liquid. This is an inexpensive and popular option that is easily applied on its own. It creates a hard film, which, however, is afraid of stones and can crack in severe frost or mechanical impact. The cracked plastic lets water through, and under it begins active rusting, which is difficult to notice visually.
⚠️ Warning: Never use pure engine oil or working out to process arches outside. These substances will wash off after the first rains, leaving a greasy film on which sand will stick, turning the arch into an abrasive grater.
For hidden cavities and internal surfaces, arches are best suited waxy or oil compounds with corrosion inhibitors. They have a high penetrating ability, displace moisture and create a protective layer in hard-to-reach places where thick mastics simply will not get.
Preparation technology: the key to the durability of the coating
The quality of anticorrosion treatment is 90% dependent on surface preparation. Applying any composition to dirt, loose rust or fat will only lead to a temporary effect. The first step should always be thorough. sink a car, preferably using a high-pressure kerkerker to knock out all the dirt from the hidden cavities.
After washing, a defect must be made. If there are already paint bloating or corrosion foci on the metal, they must be cleaned to pure metal. For this purpose, grinding machines, sandpaper or special nozzles on the drill are used. It is impossible to leave rust under the layer of anticortex - the oxidation process will continue with a vengeance.
The most important step is degreasing. The surface must be absolutely clean to ensure adhesion (adhesion) of the material to the metal. Use special degreasing agents or White spirit. After surface treatment, a rust converter is often required, if it is impossible to completely remove the oxides mechanically, and subsequent priming.
☑️ Preparation for anticory
If you plan to use moisture-sensitive materials (such as some types of epoxy soils), make sure the metal is completely dry. The residual moisture under the coating will start the corrosion process immediately after the protection is applied.
Comparative table of protective coatings
To make it easier for you to choose the right material, we have systematized the main characteristics of popular types of protection in the table below. Please note that the service life is approximate and depends on the operating conditions and quality of training.
| Type of coating | Resistance to impact | Elasticity | Difficulty applying | Average service life |
|---|---|---|---|---|
| Bitumen mastic | Medium | Tall. | Low. | 2-3 years |
| Liquid plastic | Low. | Low. | Low. | 1-2 years |
| Polyurethane composition | Very high. | Medium | Tall. | 5-7 years |
| Rubber paint | Tall. | Very high. | Medium | 3-4 years |
| Wax anticor (hidden cavities) | Low. | Tall. | Medium | 1-2 years |
From the table, it is clear that there is no universal solution. For external surfaces exposed to impacts, elastic and durable compositions are better suited, and for hidden cavities - penetrating liquids.
Do you need plastic slats (lockers)?
Plastic slats, or lockers, are often perceived as a panacea, but this is not quite the case. On the one hand, they take the brunt of sand and stones, protecting the paintwork of the arch. On the other hand, between the plastic and the metal of the body inevitably accumulates moisture and dirt.
If under the locker is not carried out high-quality anti-corrosion treatment, the presence of plastic protection can even accelerate rot. The water that gets there dries up for a very long time, creating a greenhouse effect. Therefore, installation of lockers without pre-treatment of metal categorically not recommended.
The optimal solution is a combination of methods: high-quality metal processing with anticord, and on top - the installation of lockers. It is important to ensure that the mounting of the underwings do not damage the protective layer, and the plastic itself lies tightly, not collecting water as in a bath.
⚠️ Note: When installing new underwings, be sure to treat the places of attachments (shooters or clips) with anticor or sealant. Metal drilled under the fasteners is ready-made corrosion centers.
Instructions: how to handle the arches with your own hands
If you decide to take up the case yourself, you will need a set of tools: a drill with brushes, degreaser, brushes, spray gun (for some types of compounds) and, of course, the anticor itself. Work is better to carry out on the street or in a well-ventilated room, as many formulations are toxic and fire-prone.
Start by removing wheels and plastic underwings. Carefully clean the arches of dirt and old, flaking protection. If there is through corrosion, it must be cut and brewed, or use special repair putty with zinc, although this is already body repair.
Apply the material evenly, leaving no gaps. For hidden cavities, use special spray nozzles that allow you to feed the composition inside the structure. It is critically important to process welded seams and places of fastening of body elementsBecause that’s where the destruction begins.
Sequence of application:1. Ground (if required by the instructions)
2. The main layer of anticores
3. Finish layer (after 2-4 hours)
Allow the coating to dry according to the manufacturer's instructions before installing the wheels. It usually takes 12 to 24 hours for complete polymerization.
Can I apply anticores to rust?
There are converter compounds that can be applied to rust, turning iron oxides into a protective layer. However, mechanical cleaning always gives a more reliable and durable result. Transducers are a temporary solution or preparation for painting, but not a full protection for years.
Common errors in anticorrosion treatment
One of the most common mistakes is saving on preparation. An attempt to save time and apply "antigravium" directly on top of dust or greasy spots will lead to the fact that after a month the coating will begin to fall off in layers along with rust. adhesion It's the foundation of all protection.
Another mistake is the use of incompatible materials. For example, applying bitumen mastic over nitro-emali or certain types of soils can cause a chemical reaction, swelling and detachment. Always read the instructions on the can, the manufacturer usually indicates which surfaces the composition is compatible with.
Use a flashlight and mirror on a long handle to visually control the coating in hard-to-reach arch areas. What you can’t see can be unprocessed.
Also, do not forget about regular maintenance. Even the best defenses don't last forever. Once a year or two, it is recommended to inspect the condition of the cover and, if necessary, update it, especially after the winter season or off-road trips.
⚠️ Warning: Do not try to blow out the anticort ventilation holes of the body. This will disrupt air circulation and lead to condensation inside the sills and spars.
How to extend the life of the protection of arches
After the work, it is important to properly take care of the car. Regular washing, especially in winter, helps to remove aggressive plaque of reagents. Use self-service washers with an "active foam" function that flushes dirt from the arches well.
Try to avoid long trips on deep mud and snow porridge unless your car is prepared specifically for off-road. Mechanical damage to the protective layer negates all efforts. If you notice a chip or scratch on the treated surface, cover it with a small amount of anticoric or paint.
Regular washing of wheel arches in winter is the cheapest and most effective way to extend the life of anticorrosion treatment.
Following these simple rules will allow you to forget about the problem of rusty arches for many years. Remember that the body is the most expensive part of the car, and its safety directly affects the residual value of the car when sold.
How often should I update my corrosion coating?
Depends on the material. Bitumen mastics and liquid plastics require renewal every 1-2 years, as they quickly lose their properties. High-quality polyurethane compositions and rubber coatings can last 3-5 years or more. It is recommended to inspect the condition of the arches every autumn.
Can I apply anticory over rust?
Only if they are special rust converters. Conventional protective compositions (antigravium, mastic) should be applied only to pure, primed metal. Applying protection over loose rust will end up with the metal rotting under the coating unnoticed by the owner.
What is the difference between anti-gravity and anti-cor?
Antigravity is usually a thicker rubber crumb compound designed to protect against mechanical impacts of stones. Anticores are a more fluid, penetrating composition, often on an oil or wax basis, to protect against moisture in hidden cavities. Both types are often used for full protection.
Do I need to remove the wheels for processing?
Yes, the removal of wheels is necessary for high-quality processing. This allows access to the bottom of the arches, sills and mounting places of the underwings, which are the main centers of corrosion. Handling without removing the wheels will be superficial and inefficient.
How much dried anticor after application?
The drying time depends on the air temperature and the type of composition. On average, a surface film is formed in 1-2 hours, but complete polymerization takes 12 to 24 hours. In the cold season, the drying time increases.