Attaching license plates seems to be the simplest task that every vehicle owner faces when purchasing or after replacing registration plates. However, this is where many nuances lie, ignoring which can lead to serious fines from the traffic police or the loss of expensive signs on the road. License plate screws - this is not just a consumable material from the nearest store, but a specific fastener that has strict regulations on sizes and materials.
In this article, we will analyze in detail what types of fasteners exist, how self-tapping screws differ from bolts and nuts, and why the use of unsuitable fasteners can cause the car’s registration to be revoked. You will learn about modern anti-theft systems and understand how to correctly install the license plate so that it does not fall off after a month of use in winter conditions.
Standards and requirements for license plate mounting
The main document regulating the installation of state registration plates (GRP) in Russia is GOST R 50577-2018. Although the standard primarily describes the requirements for the signs themselves, it indirectly dictates the rules for their installation. Fasteners should not cover the symbols, change their geometry or create glare that interferes with the reading of cameras recording violations. The use of non-standard frames or fasteners that hide at least part of a number or letter is equivalent to installing a modified number.
It is important to understand that the holes in the license plate are already provided by the plate manufacturer. They are located symmetrically and have a standard diameter designed for the most common types of hardware. If you try to use one that is too thick bolt, the metal of the license plate may become deformed or crack, especially if silumin or a low-quality alloy is used. On the other hand, a screw that is too thin will hang loose in the hole, which will lead to vibration and eventual loss of sign.
⚠️ Attention: The use of frames that completely hide the edges of the number, or fasteners with decorative caps that overlap the symbols, is a direct violation. The fine for this is 5,000 rubles or deprivation of rights for up to 6 months.
Modern requirements for readability numbers have become stricter due to the widespread introduction of Plato systems and Potok cameras. Even a slight displacement of the plate due to a poorly selected screw can lead to the recognition system making a mistake in one digit. This is fraught with fines for other people’s violations or, conversely, the inability to prove one’s innocence if the camera counted the number incorrectly.
Types of fasteners: self-tapping screws, bolts and rivets
There are three main types of solutions for mounting grommets on the automotive fastener market. The choice depends on where exactly you plan to mount the number plate: directly into the car body, into a plastic bumper, or into a special holder frame. Each option has its own advantages and disadvantages that must be considered before purchasing.
Self-tapping screws for metal and plastic are the most popular option for quick installation. They do not require a thread in the mating part, as they cut it themselves. However, for plastic bumpers, ordinary self-tapping screws may not be enough: they can become unscrewed due to vibration. In such cases, experienced craftsmen recommend using special self-tapping screws with press washer, which provide a large pressing area.
Bolts with nuts are considered a more reliable, but labor-intensive solution. To install them, you need to drill a through hole in the bumper or trunk lid and have access to the reverse side to tighten the nut. This method is often used on domestic cars and trucks where the metal is thick enough to hold the nut securely.
- 🔩 Self-tapping screws — ideal for mounting in plastic frame holders or thin metal, do not require access to the reverse side.
- ⚙️ Bolts with nuts — provide maximum reliability, but require through drilling and access from both sides of the part.
- 🔨 Rivets — disposable fasteners that provide a high degree of protection against unscrewing, but require special tools for installation and dismantling.
⚠️ Attention: When using bolts with nuts, be sure to use a thread locker (spring washer) or a thread locking compound, otherwise the vibration will inevitably cause the nut to unscrew.
Deserves special attention anti-vandal screws. They have caps with a special profile (for example, a star with a pimp or a tetrahedron), which require a special key to unscrew. This is an effective protection against number theft, which, unfortunately, is becoming increasingly important in large cities.
Dimensions and threads: how not to make a mistake with your choice
The question of the size of fasteners for GRZ often confuses inexperienced car enthusiasts. The standard European and Russian hole size in the number is 9 mm, but this is not the diameter of the screw itself, but the diameter of the hole for the head or place for the tool. Himself thread diameter most often varies from 4 to 6 mm.
The most common thread for attaching numbers is M5 and M6. The M5 thread (diameter 5 mm) is more often found on foreign cars and in plastic frames, while M6 (diameter 6 mm) is the standard for more massive mounts and domestic cars. The length of the screw is selected individually depending on the thickness of the material into which it is screwed.
To select the correct length, it is necessary to take into account the sum of the thicknesses: the thickness of the license plate (usually 1 mm), the thickness of the frame-holder (if there is one, about 3-5 mm) and the depth of insertion into the base material (at least 5-7 mm for reliable fixation).
| Fastener type | Thread diameter | Recommended length | Base material |
|---|---|---|---|
| Self-tapping screw | 4.2 - 4.8 mm | 12 - 16 mm | Plastic, thin metal |
| Bolt | 5.0 mm (M5) | 15 - 20 mm | Body metal, bumper |
| Bolt reinforced | 6.0 mm (M6) | 20 - 30 mm | Frame, thick metal |
| Anti-vandal screw | 5.0 mm (M5) | 15 - 25 mm | Any (with special key) |
When purchasing fasteners, always take a sample with you or know exactly the parameters of your car. There is no universal solution “for everyone,” since the depth of the seat on different car models can differ by several millimeters, which is critical for short screws.
Materials and corrosion protection
An aggressive external environment is the main enemy of any fastener. Road agents, salt, moisture and temperature changes can turn an ordinary black self-tapping screw into rusty dust after just one winter season. Rust not only spoils the appearance of the car, but also “sticks” to the threads, making removing the license plate without damaging the paintwork almost impossible.
The best material for automotive fasteners AISI 304 or AISI 316 stainless steel is considered. Such screws and bolts do not rust, retain a presentable appearance and are easily unscrewed even after years of use. Their only disadvantage is their higher cost compared to conventional steel fasteners.
If you are using regular steel fasteners, make sure they have a quality zinc or nickel coating. Chrome plating has also proven itself in the automotive industry. However, even the best zinc can be destroyed by aggressive chemicals over time, so additional processing will not hurt.
Before installing new screws, lubricate the threads with graphite lubricant or copper spray. This will prevent the metal from sticking and will make it easy to rent the room in the future, even after a few years.
Plastic plugs not only play a decorative role by covering the screw heads, but also protect the threads from water and dirt. However, they must fit tightly. Cheap plastic becomes brittle in the cold and bursts, ceasing to perform its function.
Instructions for installing a license plate
Correct installation of the gas protection device requires preparation and care. You should not try to screw the number on by eye, hoping that the holes will match perfectly. First, try it on: attach the number to the installation site and make sure that it sits evenly, is not skewed, and all holes match the seats on the car or frame.
If you attach the number directly to the body or bumper, marking the holes is required. Use a marker to mark the centers of future holes through the holes in the number. When drilling plastic, use a drill bit with a stopper or control the depth manually to avoid damaging the internal components of the bumper.
☑️ Check before installation
Do not overtighten the screws while tightening. Excessive force can lead to deformation of the metal plate (it will bend in a “bubble”) or a crack in the plastic of the bumper. The screw should be tightened tightly, but without fanaticism. If a frame holder is used, make sure that it does not wobble, but does not put too much pressure on the license plate.
⚠️ Attention: Never use welding or glue “tightly” to fix the number. This violates the vehicle operating rules and makes replacing the license plate or removing it for washing/polishing impossible without damage.
After installation, be sure to wipe the number and check its legibility. Make sure screw heads or decorative elements do not overlap any characters, including thin lettering and numbers.
Anti-vandal protection and modern solutions
The theft of license plates is, unfortunately, a common occurrence. Attackers are interested not so much in the metal plates themselves, but in the possibility of using them to commit other offenses or simply commit hooligan acts. To protect against such situations, there are special anti-vandal kits.
The essence of the protection is to use screws with a non-standard head profile. To unscrew them, you need a special key, which is usually included and kept at the owner’s home. Without this key, it is almost impossible to unscrew the number with a regular screwdriver or pliers - the edges are licked off or the mechanism itself is turned.
Another modern solution is frames with rotating mechanism or telescopic frames. They allow you to hide the number by rotating the frame or pulling it out. Although such devices are popular among drivers who want to hide their license plate from cameras, their use is illegal and amounts to driving a vehicle without license plates or with modified plates.
What to do if the screw is broken?
If the screw head is stripped or rusted, try using an extractor. Carefully drill through the center of the cap, drive in the extractor and unscrew the remaining screw counterclockwise. Be careful not to damage the surrounding bodywork.
It is better to use minimalistic solutions that guarantee reliable fixation without breaking the law.
The main goal of choosing fasteners is not only reliable fixation, but also the ability to quickly dismantle if necessary, as well as compliance with GOST requirements in order to avoid fines.
Frequently asked questions (FAQ)
Is it possible to mount the number with just two screws on top?
Formally, GOST requires that the number be attached to the places provided by the manufacturer. If there are 4 holes in a number and you only use the top 2, this may be considered a violation of the installation rules. In addition, the bottom of the number will wobble, causing it to break or be lost. It is recommended to use all holes.
What size screws are needed for logo frames?
Frames with logos often require longer screws, as the frame itself can be up to 5-7mm thick. Standard short screws may simply not reach the seat in the car. Use screws that are at least 20mm long and make sure that they do not touch the internal parts of the bumper.
Do the screws need to be lubricated before installation?
Yes, this is highly desirable. Thread lubricant (graphite, copper or even lithium) prevents corrosive seizing (sticking) of metals. In a year or two, you will thank yourself when you can easily unscrew the number for washing or replacement without tearing off the edges.
What should I do if the holes in the license plate do not match the holes in the bumper?
Do not try to bend the number or force the screws in at an angle. This will damage the paintwork and deform the sign. In this case, it is necessary to either drill new holes in the bumper (carefully marking them by number), or use a universal adapter frame that has more holes or sliding fastening elements.
Is there a fine for using colored caps on screws?
Colored blanks themselves are not prohibited, as long as they do not overlap the symbols of the number and do not distort its perception. However, if the color of the plugs matches the color of the special signals or makes the number difficult to read (for example, shiny plugs cause glare on the camera), the inspector may issue a warning or a fine for violating the rules for installing a gas protection device.