Many car enthusiasts, in an effort to improve driving comfort, are thinking about installing additional protection elements. The question often arises: what are the plastic covers on car windows from rain and dirt called? The correct name for these accessories is deflectors. The origin of the term goes back to the Latin word meaning "to deflect", which accurately describes their main function.
These devices are aerodynamic visors that are attached to the top of the door frame or directly to the glass. They allow you to open the windows slightly even in heavy rain, preventing drops of water from entering the cabin. In addition, the deflectors effectively remove air flow, creating a zone of peace for the driver and passengers.
The history of their appearance is connected with the development of high-speed automobile production, when windows open while driving created a lot of noise and discomfort. Today it is not just a utilitarian detail, but also an element tuning, capable of changing the appearance of the car. In this article we will examine in detail all aspects related to the selection and installation of these useful accessories.
Functional purpose and operating principle
The main task of deflectors is to redirect air flows. When the car moves, air flows around the body, creating zones of high and low pressure. The plastic visor changes the aerodynamics in the area of the window opening, removing dirt, dust and water to the side. This allows you to keep the interior and side mirrors clean.
In addition to protecting against precipitation, these covers solve the problem of glass fogging. Air circulation The inside of the cabin improves significantly when the windows are opened a couple of centimeters. This is especially true in the off-season, when the temperature difference between inside and outside causes condensation to form.
⚠️ Attention: A poorly made deflector can create a whistling sound at high speeds. Choose models with proven aerodynamics.
It is also worth mentioning protection from direct sunlight. The slight shade created by the visor increases driver comfort by reducing heat on the side of the face and hands. This is especially important for long trips on the highway in the summer.
The deflector works by changing the direction of air flow, creating a barrier to moisture and dirt without completely sealing the cabin.
Varieties of materials and designs
There are many options available on the modern car accessories market. The main difference lies in the materials used. Most common acrylic models that are highly transparent and elastic. They lend themselves well to molding and rarely crack during installation.
The second popular option is polycarbonate products. This material is characterized by increased strength and resistance to mechanical damage. However, polycarbonate can be less flexible, requiring special care when installing on complex curved glass surfaces.
- 💎 Acrylic: high transparency, flexibility, medium scratch resistance.
- 🛡️ Polycarbonate: maximum strength, rigidity, excellent UV resistance.
- 🌫️ Tinted: have a darkening effect that hides defects and gives a stylish look.
We should also highlight the chrome inserts, which are often integrated into the design of the deflector. They perform a decorative function, adding premium quality to the car. Chrome can be applied to the entire surface or only to the outer edging.
Fastening methods: adhesive and plug-in
The choice of fixation method plays a critical role in the durability and aesthetics of the product. There are two main methods: gluing and spacer installation. Glue method involves the use of double-sided tape applied to the inside of the deflector. This provides a secure hold, but requires perfect surface preparation.
Plug-in deflectors, or “in spacers,” are installed between the glass and the rubber seal of the door frame. This option is considered more gentle on the body, as it does not require the use of glue. However, it may be less reliable at high speeds or when pressure washed.
Some manufacturers offer combined fastening systems. They combine a rigid insert into the seal and additional adhesive fixation points. This allows you to combine reliability and ease of installation. When choosing, it is important to consider the geometry of your car windows.
Advantages and disadvantages of use
Installing deflectors has both its pros and cons, which should be weighed before purchasing. Obvious advantages include the ability to ventilate the interior in any weather. You can smoke or just breathe fresh air without fear that the interior will be flooded with rain.
In addition, these covers protect the side windows from small stones and gravel flying from under the wheels of cars in front. This reduces the risk of chips and scratches on the glass. In winter, deflectors help remove moisture faster, preventing the formation of an ice crust.
⚠️ Warning: Deflectors that are too wide may block your view of the side mirrors, creating blind spots.
Among the disadvantages, an increase in interior noise at speeds above 100 km/h is often cited. Also, cheap models may lose transparency over time, turn yellow or peel off. An incorrectly installed element may cause knocking or vibration.
Instructions for correct installation
The installation process requires care and adherence to temperature conditions. It is best to carry out work in a garage at a temperature not lower than +15°C. If you use the glue method, the surface must be thoroughly degreased with alcohol or a special cleaner.
For plug-in models, it is important not to damage the rubber seal. Before installation, it is recommended to lubricate the edge of the deflector and the rubber band with soapy water or silicone grease. This will make it easier to slide and prevent the material from tearing.
☑️ Checklist before installation
After installing adhesive deflectors, it is not recommended to open windows for 24-48 hours. This time is necessary for the glue to fully polymerize and gain maximum strength. Ignoring this rule can lead to the element tearing off during the first movement.
The secret to reliable adhesion
For better adhesion of the glue to the surface, you can slightly warm up the deflector itself and the body with a hair dryer to a temperature of 40-50 degrees, but do not overheat the plastic!>
Comparison table of characteristics
To simplify the choice, let's look at the main parameters of different types of deflectors in comparison. The data will help you understand which option will be optimal for specific operating conditions.
| Parameter | Acrylic | Polycarbonate | Plug-in |
|---|---|---|---|
| Transparency | High | Average | Depends on material |
| Flexibility | High | Low | Average |
| Difficulty of installation | Average | High | Low |
| Price | Average | High | Low |
As can be seen from the table, each type has its own characteristics. Acrylic is good for complex shapes, polycarbonate is for those who value durability, and plug-in options are suitable for quick installation without chemicals.
Care and maintenance of accessories
To maintain their appearance, deflectors require regular maintenance. When washing your car, avoid using aggressive solvents and abrasive sponges. They may leave dull marks or scratches on the surface of the plastic.
It is recommended to periodically treat the surface with plastic polish. This will restore shine and create a protective layer that repels dust. If you notice that the edges have begun to come off, you can glue them with a special automotive sealant.
During winter, be careful when removing ice from your windows. The scraper can easily damage the edge of the deflector or tear it out of place if it is frozen to the body. Always check the mobility of the element before opening the window.
Common mistakes during selection and installation
One of the most common mistakes is buying universal deflectors. They rarely perfectly match the geometry of the windows of a particular car, which leads to gaps and whistling. Model Products designed specifically for your brand and year are always preferable.
Another mistake is ignoring the fitting before removing the protective film from the tape. When you place the deflector dry, you may notice distortions or misalignments that can be easily corrected. After gluing, this will no longer be possible.
⚠️ Attention: Do not try to bend the deflector too much when installing - the plastic may not regain its shape and may burst after a while.
Also, do not skimp on the quality of the adhesive base. Cheap tape quickly loses its properties when exposed to moisture and temperature changes. It is better to use original consumables or proven analogues from well-known brands.
Is it possible to drive with deflectors in a car wash?
On automatic brush washes, it is better to lower the windows or be prepared for the fact that the brush may touch the edge of the deflector. On high-pressure washers (Karcher), you should avoid direct jetting into the joint between the deflector and the glass at an angle, so as not to tear off the glue.
Do deflectors affect fuel consumption?
Theoretically, any protruding element increases aerodynamic drag. However, modern deflectors have a streamlined shape, and their effect on fuel consumption is less than 0.1 liter per 100 km, which is almost unnoticeable in real operation.
Do I need to remove the deflectors in winter?
There is no need to remove them; high-quality materials are designed for a wide temperature range. However, in winter the plastic becomes more fragile, so mechanical impacts and sudden movements should be avoided when clearing snow.
How to remove the glue after removing the deflector?
Residues of glue can be removed using special bitumen and glue cleaners, which are sold in car dealerships. Heating with a hair dryer and gently scraping with a plastic spatula also helps.