8 best seam sealants for the car body and the secrets of their application

The main function of any sealant is the insulation and sealing of various joints and surfaces. When repairing a car body, such tools are indispensable: they help to glue parts and reliably protect the seams from moisture and dirt.

Content:

• Sealant selection criteria
• Types of suture sealants
• Acrylic Blends
• Anaerobic Sealants
• Silicone sealants
• Polyurethane Compounds
• Bituminous mixtures
• Types of body sealants by application method
• Sprayable Moisture Sealant
• Brush Sealant
• Sealant tape
• Extruded sealants
• Featured Products
• Merbenit XS55
• BODY 999
• 3M 08537
• Terostat 9320
• Novol Gravit 630
• Reoflex Brush Sealant
• Bool
• APP PU50
• How to use sealant correctly
• How to remove sealant

Most often, when using bodywork, a suture sealant is used that has suitable technical characteristics and a convenient form of release.

Sealant selection criteria

In automotive stores, a variety of sealants are sold: for hatches, bodies, pipe joints. They differ in terms of heat resistance, elasticity, and service life. The most high-quality, but expensive are professional products that are sold in large containers and are usually used in auto repair shops.

For home use they buy sealants in tubes of a suitable volume (40-200 g). If you decide to give preference to the latter option, it is better to purchase the material in an aluminum tube: it completely retains its properties throughout the entire shelf life. Cheaper products are presented in plastic tubes, but the purchase should be sure to check the remaining shelf life: it should be at least 6 months.

Some sealants have a convenient dispenser tip: they can be easily applied even to surfaces in hard to reach areas. The body sealant in the cartridge requires an additional purchase of a glue gun, without which it will not be possible to use the product.

Types of suture sealants

Any joint sealant for a car has a reliable composition, otherwise it will not be able to provide the proper level of joint sealing. Nevertheless, the materials are not the same in basis, therefore they differ in properties and characteristics.

Acrylic Blends

Acrylic sealants are prepared on the basis of polymer compositions. They have good adhesion to the surface, but with strong vibration or shock loads can peel off due to medium elasticity. It is best to use such tools for porous materials and stable nodes, seams. Any sealants with acrylic can be painted, varnished.

Anaerobic Sealants

Such products are easy to distinguish from the rest: they have a liquid texture, due to which they are called “liquid gasket”. The sealant is distributed inside the cavities and the smallest cracks, and hardens only after the termination of contact with oxygen. Typically, anaerobic compounds are used to repair small areas, otherwise there is a risk of insufficiently strong joints. Most often, the compositions are used by professionals, because they must be applied correctly and strictly follow the instructions.

Silicone sealants

They are considered the best option for home repair of metal products.Such sealants are easy to apply, quickly harden, retain strength and elasticity over time. Silicone is impervious to moisture even at high pressure, is not afraid of temperature changes. With significant humidity, it freezes very quickly - in 10-15 minutes. Typically, products are applied from a tube with a long nozzle. They can fill in bumps up to 6 mm deep.

Polyurethane Compounds

These sealants are the most popular on the market, available in a huge assortment. They are sprayed, pasty under the brush application. Distinctive features of polyurethane sealants are:

• ease of use;
• lack of spreading from vertical bases;
• high flexibility, elasticity, heat resistance, moisture resistance;
• withstanding large mechanical loads.

Bituminous mixtures

Presented in the form of compositions based on bitumen with the addition of modifiers, fillers, adhesion promoters. They look like a paste of dark color. They do not require thorough surface preparation; they are suitable for most materials, including any metals. They can be used in a humid environment and tolerate direct contact with water.

Types of body sealants by application method

You can determine how the sealant is applied by its texture and type of packaging. Also, the application method is always indicated in the instructions for use of the composition.

Sprayable Moisture Sealant

Typically, such polymers are based on such agents. The compositions are one-component, contain a large amount of solids, so they quickly freeze in the air under the influence of humidity and form a very durable seam. Sprayed sealants are applied with a special spray gun. It is especially convenient to work with them in the areas of the underbody, engine compartment, car trunk.

Brush Sealant

Such compounds are made on the basis of silicone, nitroresin, they are sold in banks of 1 kg or more. Sealants can seal docking and welds, glue jumpers, flavors, pallets, seal the trunk, wheel niches. Typically, funds are available in white, gray, black. They are applied with a brush, dry in literally 10 minutes and can immediately be stained.

Sealant tape

Applying sealant to a car often requires a lot of skill, otherwise the seam will not work perfectly even. If there is no confidence in your own skill, a tape is used that is very easy to use. Tape sealant does not need to be lubricated with glue - it already has an adhesive base. Flexibility allows you to apply the material in any place during body repair. Immediately after gluing, the tape can be painted - it does not require drying.

Extruded sealants

Such compositions are sold in tubes and cartridges. To close joints, seams, the material must be squeezed onto the parts to be joined manually or with a gun. The seam will be the most uniform when using a pneumatic gun. Typically, these tools are used to seal the seams of the hood, the inside of the doors, engine compartment, trunk.

Featured Products

To choose a good automotive sealant for joints, you should pay attention to the most famous and high-quality products on the market.

Merbenit XS55

It is a high-strength sealant for the hood, underbody and other body parts based on a modified silicon base. It has tremendous tensile strength (4 N / sq. Mm), excellent adhesion to metal, plastic. In addition to sealing joints, it can be used in the installation of HVAC equipment, ventilation.In the factory, it is used in the automotive industry, car building, in the production of polymers. Advantages of sealant are doubtless:

• perfect filling of even the smallest cracks;
• the possibility of painting the finished seam;
• lack of harmful solvents and an unpleasant smell;
• resistance to the action of water, salt, oils, solutions of alkalis and acids;
• tolerance of vibration, shock, atmospheric effects.

BODY 999

Body 999 sealant can be found in any car shop. It is considered one of the most common and is sold in 150 ml tubes, 300 ml cartridges, and 1000 ml cans. The agent on a polyurethane basis is used to fill voids, process welds of the machine in order to protect it from water and the harmful effects of atmospheric factors. The sealant is perfect for metal, plastic, painted surfaces, but it can not be applied to areas exposed to ultraviolet radiation.

The advantages of the material are as follows:

• maintains elasticity over a long period;
• does not shrink;
• does not flow on vertical surfaces;
• can be applied even with a thick layer and not crack;
• has a high degree of adhesion to surfaces;
• ready to use, does not require dilution;
• after drying it can be painted.

3M 08537

3M suture car sealant is also made on the basis of polyurethane. This is a one-component composition, available in black and white, considered universal and suitable for:

• panel connections;
• sealing welds;
• processing arches, sills, doors;
• seals of the bottom, joints inside the trunk;
• shock absorber mountings;
• hardening bolted joints.

The tool has a brush method of application, is liquid and is available in metal cans. It is resistant to oils, petrochemicals, highly elastic, not afraid of water, does not shrink, retaining its structure for several years, dries quickly. After the final polymerization, the seam will be solid, but elastic enough. 50 minutes after application it can already be painted with any paints.

Terostat 9320

The sealant of the Teroson line ("Teroson") Terostat 9320 is considered a universal 4-in-1 agent. This is a sprayable one-component composition based on modern modified polymers, which freezes under the influence of moisture from the air. It is available in black, gray and ocher.

After polymerization, thermostat adhesive-sealant forms an elastic, abrasion-resistant joint, which will not look different from the factory one. The material has a high degree of adhesion to metals, is compatible with any paints, primers and primers, is resistant to UV radiation, shrinkage, sagging, aging, quickly freezes in air.

Novol Gravit 630

Sealant Novol Gravit 630 is a one-component polyurethane product used for sealing welded joints, soldered joints. It creates an elastic and very durable shell, which over time does not shrink, does not crack, does not wrinkle. Sealant "Novol" has good adhesion to metal, as well as varnished tin. Ready seam can be covered with acrylic paints. The product is applied with a special gun. Its only negative can be called low resistance to ultraviolet radiation.

Reoflex Brush Sealant

The sealant under the brush of the Reoflex brand is designed to seal any joints on metal, concrete, wood, and is widely used in body repair. It has high anticorrosive, soundproofing properties, easy to apply, dries quickly. After polymerization, the sealant forms an elastic seam that is externally close to the factory one.

Bool

Bool polyurethane adhesive sealant is available in cartridges for a 310 ml gun.It is widely used to strengthen the seams between hatches, headlight holders, metal parts, gutters. Ready seam can be painted with all types of varnishes. The tool is sold in white, beige, black colors.

APP PU50

This material is one-component, made on the basis of polyurethane. APP has a high degree of adhesion to primed, painted metal, stainless steel, glass, all types of plastic, concrete and aluminum. In body repair it is used for sealing welded joints. The method of application of the material is special: first you need to put it on the seam in the form of a roller, then spread it with a spatula, brush.

How to use sealant correctly

The application of auto-sealants has its own nuances, and in order to obtain a high-quality result, one must strictly observe the following rules:

• thoroughly clean the surface before work, remove rust, degrease;
• to enhance adhesion, clean the bases with red scotch tape;
• primer with special primers for metal, if this measure is indicated in the sealant instructions.

To seal the joints, you need to prepare the composition: if necessary, dilute or print the tube, insert the cartridge into the gun, open the packaging with tape. Also, a spatula, brush may be required to work. After that, it is necessary to apply the composition to the area of ​​the future seam, acting at the same speed along its entire length - this will help to make the joint smooth, like a factory one.

Excess sealant should be removed immediately with a spatula, with your fingers. If the composition is very sticky, you can sprinkle it with water a little. In the future, it is allowed to stain the seam, but only after the time specified by the manufacturer. This usually becomes possible after the complete cure of the sealant.

How to remove sealant

If the composition is incorrectly applied or if the old sealant is present, the seam must be removed and the work performed again. To clean the hidden joints, use the mechanical method - remove the layer of material with a sharp spatula, knife, pumice, emery paper. In order not to scratch the base for sure, you can use the chemical method - moisten the sealant with white spirit, and then separate the softened composition with a knife. After preparing the base, a new layer of sealing agent can be applied following the manufacturer's instructions.