Car body restoration and repair. Price list and prices for car body repair. Repair of bodies and cabins

Abstract on the topic:

"Repair of bodies and cabins"

Is done by a student

3 courses 33-AK group

Speciality:

MOT and car repair. and tr-a

1. Defects of bodies and cabins…………………………………………3

2. Technological process of repairing bodies and cabins ……………. 4

3. Repair of equipment and mechanisms of the body and cabins ………… .. 6

4. Repair of non-metallic body parts ……………………. 6

5. Assembly and control of bodies and cabins ………………………………… .. 7

REPAIR OF BODIES AND CABINS.

Defects of bodies and cabins.

Typical defects of body parts, cabins and empennage (Fig. 1) are corrosion damage, mechanical damage (dents, breaks, tears, bulges, etc.), violation geometric dimensions, cracks, destruction of welded joints, etc.

Corrosion damage is the main type of wear on metal bodies and cabins. Here, an electrochemical type of corrosion takes place, in which the metal interacts with an electrolyte solution adsorbed from the air. Corrosion develops especially strongly in places that are difficult to clean, where moisture that periodically gets into them persists for a long time, and, due to an increase in ambient temperature, an intensification of the oxidation reaction occurs. Corrosion damage also occurs as a result of contact of steel parts with parts made of duralumin, plastic, damp wood and other materials.

Cracks occur as a result of metal fatigue, violation of metal processing technology, the use of low quality rollers, assembly defects of assemblies and parts, insufficient structural strength of the assembly, as well as in places subject to vibration.

Destruction of welded joints occurs as a result of poor-quality welding, exposure to corrosion, vibration and stress during normal vehicle operation or as a result of accidental damage.

Mechanical damage (dents, distortions, breaks, etc.) is the result of metal overstrain as a result of impacts and bends, as well as due to fragile connection of parts.

Fig. 1. Typical damage :

a -all-metal body car :

1 - front and rear windshield openings;

2 - doorways;

3 - roof racks;

4 - front and rear side members;

5 - left and right thresholds of the base;

6 - bottom;

7-left and right rear mudguards

8 - violation of geometric dimensions;

9 - top and bottom, respectively, of the left and right rear mudguards;

10 - left and right front mud flaps;

b - truck cab :

1 - destruction of welding seams; 2 - breaks; 3 - dents and bulges; 4 - deflection and distortion of the struts; 5 - holes; 6 - corrosion; 7-cracks

Technological process of repairing bodies and cabins.

The technological process of repairing assembled bodies and cabins includes disassembly, complete or partial removal of old paint, troubleshooting, repair component parts or their replacement, assembly, painting and quality control.

Dismantling of bodies and cabins is performed in two stages. This is the dismantling of all parts and assembly units installed on the inner and outer sides of bodies and cabins, followed by disassembly of the body for repair after removing the old one. paintwork and identifying all its defects. Since in most cases the all-metal bodies of bodies and cabs are one-piece (connected by welding), the complete disassembly of the body into panels and parts is not performed. It is carried out only to such an extent that it is possible to carry out flaw detection and, if necessary, replace or repair the body elements that form the frame.

Depending on the economic feasibility of repairing bodies and cabins, they use different ways elimination of defects on their surfaces.

The greatest labor intensity and cost of repairing bodies and cabins is made up of work to eliminate defects on their all-metal welded bodies. Repair of the body body, which has various defects, provides for straightening the panels, removing damaged sections of the bodies, eliminating cracks and tears, attaching the DRD to the places of the removed panels, forging and cleaning old seams, final straightening and straightening the surfaces.

Irregularities in the panels are leveled by spraying with powder plastics or epoxy compositions. To align dents in hard-to-reach places, use a Tool of various shapes (Fig. 2). The bent end of the mandrel is inserted into the hole of the inner panel and the dented surface is leveled with hammer blows on its handle. To eliminate shallow shallow dents, a 6 mm hole is drilled in it, into which a rod with a curved end is inserted and the concave part of the panel is pulled out to its normal position. The hole is then sealed with solder or epoxy.

Rice. 2. Dent Removal Tool Kit:

1...6 - hammers; 7 and 8 - mallets; 9 - mandrels (spoons)

Editing panels with emergency damage provides for work on pulling, leveling, squeezing and knocking out deformed parts of the body or cabin to give them their original shape and size. When performing these operations, it is necessary that the tensile force was applied at the same angle at which the force that caused the damage was applied. For the stretch to be controllable, an opposing force must be applied opposite the point of application of the tensile force. When performing these works, it is necessary to control the stretching process, as well as possible associated deformations caused by the tensile force.

Edit emergency bodies and cabins are performed on stands (Fig. 3) using a set of accessories (Fig. 4). Tensile and compressive forces are created by working cylinders 1, 3 (fig. 3), in which the liquid flows from the pump. For straightening the body 4 set on stands 6, which are fixed to the base frame 2. Power transverse pipes are supported on the supports, which are fixed with the jaws of the clamps to the stiffening ribs of the body sills. The latter is fastened to the frame with bracing devices. 5. Deep dents are removed by preliminary straightening (Fig. 4, b), bends (fig. 4, v) and distortions (fig. 4, G). Since cracks or gaps may form during the straightening process, which must be eliminated in the future, straightening is carried out before welding.

Removal of damaged areas of bodies and cabins perform gas cutting, electrified milling tool or pneumatic cutter. The advantages of the pneumatic cutter are high performance labor (0.08 ... 0.1 m / s) compared to gas cutting (0.02 m / s) and best quality edges in places of cutting. Defective areas are marked with templates and chalk and then removed. When removing defective parts of the body or cab, it is necessary to protect the body from distortions of the geometry due to the weakening of its rigidity and under the action of its own weight.

Cracks and tears in the body of bodies and cabins are eliminated by semi-automatic arc welding in carbon dioxide or gas welding. When repairing, preference is given to welding in a carbon dioxide environment, since the productivity of this process and the quality of the weld are higher. Welding is carried out by semiautomatic devices powered by sources direct current reverse polarity with a force of 40 A and a voltage of 30 V, using an electrode wire Sv-08GS or Sv-08G2S with a diameter of 0.7 mm. To limit the propagation of a crack during welding, its ends must be drilled with a drill with a diameter of 8 mm.

Gas welding eliminates cracks and breaks in panels made of sheet steel with a thickness of 0.5 ... 2.5 mm, with VSM-53 or GS-53 burners with tips No. 1 (for sheets with a thickness of B, 5 ... 1.5 mm) and No. 2 (for sheets 1.0 ... 2.5 mm), using for this wire Sv-08 or Sv-15 with a diameter of (0.5L + 1) mm, where h is the thickness of the metal to be welded. So that the part does not lose its willow shape when heated, first weld at separate points with an interval of 10 mm, and then, as necessary, separate sections are welded with a continuous seam from the ends of the crack to the middle.

Fig. 3. Body straightening stand passenger car:

1,3 - working cylinders;

2 - frame;

4 - body;

5 - brace device;

6 - stand

Making an additional repair part start with straightening the steel sheet, cutting it and cutting blanks according to the marking. After its part is bent or molded on special equipment, the finished parts are cut, drilled, straightened and cleaned. The material for the manufacture of the repair part is thin-sheet cold-rolled mild steel with a thickness of 0.7 ... 1.5 mm.

Rice. 4. Devices for straightening deformed body section:

a- a set of devices for eliminating distortions and kinks;

b, v and G- the use of fixtures for straightening;

1 - mandrel for pulling out concave parts;

2 and 3 - self-locking hydraulic clamps;

4 - a mandrel with teeth for gripping the rectifiable panel;

5 - pump;

6 - double capture;

7 – tension cylinder with pulling device;

8 – tension cylinder with grips;

9 - correct device

Forging and deburring welds necessary to strengthen the weld and give it the desired profile. It is carried out with a pneumatic hammer using a set of supports and strikers. After forging, the weld points are cleaned with an abrasive wheel installed in pneumatic or electric portable machines.

Final straightening and straightening of body panels and cabins is designed to ensure accurate assembly and remove small dents and bulges left on surfaces. Straightening is performed with a pneumatic straightening device or manually. Eliminate damage by welding.

Repair of equipment and mechanisms of the body and cabins.

Fittings for bodies and cabs include power windows, locks, door stops, door hinges, hoods, etc.

Window lifters may have the following defects: cracks and breakage of parts; skew and deformation of clips, frames and guides; loosening of riveted joints; damage to rubber seals; corrosion of parts. Window lifters and glass fixing mechanisms are disassembled, washed, inspected, repaired and assembled. During fault detection, the following are rejected: parts with breaks; springs that have lost their elasticity; clips with worn glasses that cannot be squeezed; rivets that cannot be tightened; damaged rubber seals and other parts with wear on the surfaces that affect the normal operation of the mechanism. Cracks on the parts are eliminated by welding, followed by cleaning of the welded seams, the curvature of the parts - by straightening in the cold state.

Door locks may have the following defects: cracks and breakages, damage to threaded holes, corrosion on the surfaces of the part, weakening of the springs and rivets of fastening the parts, wear of the surfaces of the parts. Repair of locks consists in their disassembly, washing in kerosene, fault detection, restoration of damaged parts, assembly and adjustment. Parts that have deep traces of corrosion, worn surfaces and breakages, springs that have lost their elasticity are subject to rejection. The cracks in the castle body are welded. The broken off screws in the threaded holes are removed. The damaged thread in the hole is welded, the weld spot is cleaned flush with the base metal, the hole is drilled and the thread is cut in accordance with the size on the working drawing. Slight corrosion deposits on the surfaces of parts are cleaned with a scraper or sanding paper and washed off with kerosene.

Door hinges may have defects: cracks and breaks, wear of holes and axles, curvature. Worn door hinge pins are replaced with new ones. Cracks and wear of holes are eliminated by welding followed by machining. Worn holes for the hinge axis are deployed under the repair size, and the curvature of the hinge is eliminated by straightening.

Repair of non-metallic body parts.

Non-metallic materials are widely used in the production of automobiles: wood, plastics, synthetic leather, glass, rubber, etc. Most of the parts made from these materials cannot be restored during repair, but are replaced with new ones manufactured at a repair enterprise or manufacturer.

Wooden platform and body parts made from coniferous sawn timber (pine, spruce) with a moisture content of no higher than 18%. The main defects are breakage, cracks, spalling, wear of holes. Parts that have destroyed spikes or nests for spikes are replaced with new ones. Wooden parts of the body platform are repaired by building them up in length or by replacing unusable boards. Boards or bars are cut into workpieces of certain sizes, planed from all sides, butt ends, cut eyelets, grooves, drilled holes, etc. For gluing wooden parts, use phenol-formaldehyde adhesives such as VIAMB-3 and casein. The sequence of work: the surface intended for gluing is processed so that the parts fit tightly to each other and ensure a uniform adhesive film in thickness; the glue is applied with a brush to the surfaces to be glued (the exposure time in air for VIAMB-3 glue is 4 min); assembly holding parts under a pressure of 0.2 ... 0.3 MPa at a temperature of 16 ... 20 ° C for 5 hours; holes from fallen knots, bolts, screws are sealed with wooden cylindrical inserts made of the same type of wood as the part to be repaired with glue, and the cracks are filled with mastics, wood putty, resin glue, or by placing wooden inserts on glue, tightly fitted in place a split crack.

Sheathing textile materials or leatherette during the repair of passenger cars are replaced with a new one, since during operation the material ages, loses its elasticity and other physical and mechanical properties.

Glass of cabins and bodies may have marks, scratches, cloudiness, yellowness, iridescence, wear from brushes and other defects. Windshields and side windows with yellowness, iridescence and wear from brushes are discarded. Risks and scratches are eliminated by grinding followed by polishing. The glass to be restored is cleaned of dirt, dust and grease. The areas of the glass marked with chalk are polished with a felt upholstery of the circle, on which a layer of paste is applied, which is an aqueous solution of pumice, with a rotation frequency of 300 ... 400 minutes - "until the marks, scratches and traces of turbidity are completely removed. Then the remaining paste is washed off the glass. glass with an aqueous solution of crocus or polyrite with a wheel speed of 700 ... 800 min - "until the required transparency is obtained. After processing, the glass is degreased.

Assembly and control of bodies and cabins.

WITHassembly of bodies and cabins when repairing cars, perform in the following sequence:

before painting, all parts and assembly units to be painted along with the body (doors, hood, tail, trunk lid, etc.) are installed on them, maintaining the required gaps between the mating parts;

after applying paint and varnish coatings, the ceiling, sidewalls and panels of interior trim of doors, glasses, seats, noise and heat insulation gaskets, door seals, electrical equipment, dashboard, parts of the ventilation and interior heating system, etc. are installed.

Subject to control: geometric deviations of the dimensions of the arrangement of groups of holes functionally connected to each other, using for this control and measuring equipment; openings of bodies and cabs and mating points are controlled by templates according to the shape of the mating part; tightness and dustproofness of the body and cab. The tightness of the assembled body is checked in sprinklers at a water pressure of 2 kgf / cm2 for 6 minutes, while the penetration of water and the formation of condensation in the lighting and alarm devices are recorded. The tightness of the door to its opening is determined by rubbing the seals with chalk. When the door is slammed, a uniform chalk mark should remain on the body or cab. Adjustment of the tightness of the door seals is achieved by moving the lock latch.

Body repair is a complete or partial restoration of the body, both removable and non-removable elements. The purpose of body repair is to identify and repair hidden and visually accessible damage. Hidden damage includes corrosion, microcracks, metal fatigue. Visual damage is dents, chips, scratches.

If your car body is made of aluminum or carbon fiber, then your car is safe. But if the body is steel, and there are about 99% of such cars, then you should think about taking care of your body. Sometimes only minor damage to the paintwork is enough for corrosion to begin, and if it is not stopped in time, it will lead to serious damage. Do not forget that this affects the safety of the suspended vehicle.

The best option for repairs there will be a specialized car service. In this case, the difference between an official car service and a specialized one will be the price. In an official car service, the price will be many times higher. If we talk about the "garage" service, then here we are talking about poor quality work, and indeed the risks of being left without a car

No, with a local repair, you can paint a part with a "spot", while modern technologies allow you to do it so well that you will never find a place to paint

Ask your question

Body modern car Is a complex structure that performs many important functions. Its renovation is the other side of the coin of importance and functionality. It is complex and time consuming.

Conditionally body repair can be divided into two stages. The first is the elimination of dents, the replacement of elements that cannot be repaired. Second - .

Particular attention should be paid to restoring the geometry and rigidity of the hidden underbody. It is these elements that are responsible for the safety and driving characteristics of the vehicle. All suspension elements are attached to it.

When saving on materials and tools for body repair, it must be remembered that such savings can affect the quality of body repair and be a consequence of common mistakes. It is about how to avoid such mistakes that you should familiarize yourself with the main features.

Features of body repair

We offer

Welding elements with conventional electrodes

It is difficult to connect body elements by electronic welding, but it is possible. Moreover, the quality of such a connection is very low.

Violation of the thermal regime

If the metal is not allowed to cool during welding, then the body may move, which will have to be additionally putty. Moreover, such defects cannot always be corrected with putty.

Replacement of parts in strict order

The first step is to replace the doors, then the fenders and sills are exposed. This is the only way to avoid the formation of gaps.

Painting out of color

This often happens if one body part is painted without a smooth transition to another. Even if the paint is matched exactly to the original, the old paint on the body has a change in hue, which is associated with fading in the sun and other environmental factors.

Shrinkage

Appear with poor quality and insufficient drying. Usually they appear after repairs, when the car is standing in the sun. Usually it is necessary to re-polish the putty after that.

Shagreen

This is the relief of the applied paint. After painting, there is usually shagreen on the body, but it is removed by polishing. But sometimes there is one that cannot be removed by polishing. Usually the defect occurs when the paint is not applied correctly, at high temperatures in the chamber, or viscous paint.

Dust in paint

Usually occurs if the car is not painted in a special chamber. But when painting in a dirty chamber, it also has a place to be.

Craters

Deepenings from the penetration of silicone, which had to be cut off with a special knife.

Burned the varnish

Appears if you work with a grinder at high speed or grind the same place for too long, not allowing the varnish to cool.

The manifestation of rust

If the welds are poorly cleaned and primed, then rust can occur in these places, which manifests itself through the paintwork.

By doing car body repair in particular, welding work, then for welding work you need to use a semiautomatic device or argon welding. With the help of such welding, metal up to 1 mm thick is cooked and the possibility of burning through the body elements is excluded.

Body damage can be light, medium, or severe. Straightening usually does not require special skills and, using professional tools and materials, everyone will be able to do it. Only certain difficulties and the need for skills can arise during straightening work after medium to complex damage to the body.

If more than 70% of the body needs repair, it will be cheaper to buy new car why not do body repair and sell the old one for spare parts.

You need to paint the car with fresh paint. The primer will help you identify irregularities and putty them with a finishing filler. It is possible to paint only after the putty and primer are completely dry.

Use a special spray gun for painting. The paint should dry in the special conditions of the camera without direct sunlight. Polishing is permissible only after the paintwork is completely dry.

One of the important issues of car body repair is painting, which must be carried out in accordance with the repair technology and using correctly selected materials: fillers, primers, paints and varnishes. The main task of the repair painting is the restoration of the factory paint and varnish coating while maintaining the main functional characteristics(mechanical strength, corrosion protection, etc.), as well as achieving the maximum correspondence of the repaired area in color and structure to the original paintwork of the body. The renovation should be invisible.

Let's consider the main technological stages of body repair: washing and degreasing, surface cleaning, filling, application of primers and finishing coatings.

With the help of a wide range of professional products for body repair, you can carry out high-quality preparation for painting and painting a car with your own hands. If the technology is followed, the result will be impressive. And the acquired skills will help to quickly and without extra money to paint the entire car or only damaged parts.

The materials that make up the repair system must meet the following requirements:

good adhesion
anti-corrosion protection
leveling (filling) ability
color for discreet repairs
suitable gloss level

It is obvious that all these factors are closely related. In order to select the optimal repair system, a good knowledge of body repair products and their characteristics is required.

What materials are needed for a standard paint repair?

As a rule, self-painting of some car parts may be required if, for example, during careless parking, scratches or scuffs appear on the bumper, as well as on the door. It is not always necessary to immediately contact the service station, sometimes the situation can be corrected on their own... It will be enough to correctly assess the scale of the necessary repairs and select high-quality materials for preparing the surface for painting and painting the car itself. If the damage is minor, you can limit yourself to a set of simple operations for standard repairs:

Putty
Leveling primer
Finishing coating: synthetic, acrylic or polyurethane enamels
Finishing coating: base paints under varnish

What is included in a full cycle repair with car painting?

If you had to deal with serious damage, which, moreover, was not liquidated in a timely manner, most likely it will be necessary to carry out a full cycle repair with subsequent painting. This process will take longer (especially if you need to remove rust) and requires the following materials:

Epoxy primer
Putty
Corrosion-protective soil
Leveling primer
Finishing coating - enamels
Finishing coat - base paints under varnish

Do not forget that the selection of products for preparing the surface of a car for painting also depends on the material from which the part being repaired is made (steel, galvanized steel, aluminum or plastic) and on the type of old paintwork (hard or soft).

Nowadays, many manufacturers make their car bodies from galvanized steel and aluminum. This provides higher corrosion resistance and durability, but at the same time requires the use of special materials for repairs. There are a number of products available for application to galvanized steel and aluminum.

Any type of body repair requires careful and correct execution of a certain sequence of operations. A missed or incorrectly performed operation can lead to the appearance of various defects in the paintwork.

Proper preparation of a car for painting: step by step instructions

Washing

We clean the place for painting

Degreasing

Putty application

Grinding

Degreasing.

Disguise under the ground.

Degreasing

Etching primer application

Application of filler primer

Drying

Removing the disguise.

Grinding

Degreasing

Disguise as paint

Degreasing

Paint / varnish application

Drying

Removing disguise

Assembly

Polishing

Washing

Dust, dirt, road salt, grease, etc. are the main enemies of any paint system. Therefore, in any type of body repair, the first step is washing.

Stage 1. Washing

What is the purpose of washing and degreasing a car when preparing a surface for painting:

to remove various salt compounds, dirt, grease, etc. (due to not washed off salt, such a defect as "bubbling" may occur);
for optimal adhesion of the repair coating (dirt that is not washed off is clogged into the risks during cleaning);
to save materials, time and money (due to dirt that gets on it, the abrasive material quickly clogs up and breaks down - the grinding time increases);
to exclude the possibility of craters (dirt remaining in the risks after stripping may contain fats or silicones);
to avoid low gloss (due to the remaining sanding product in the risks).

Stage 2. We apply disguise and clean the surface for painting

When the car is washed, you can safely start preparing the surface for painting. To do this, we designate the place where the painting work will be carried out. If we paint a separate part, its borders need to be pasted over with masking tape and thick paper. Then you need to clean up the defects (chips, scratches) with sandpaper (grain size P150-P280). This will remove layers of old paintwork and smooth out the edges.

Stage 3. Degreasing

Always use two clean wipes when degreasing - the first wets the surface, the second (dry) removes the dirt dissolved in the degreaser;
Perform degreasing in small areas (about 50x50 cm) in order to have time to wipe it with a dry cloth until the degreaser evaporates;
Degrease immediately before applying the material;
When degreasing, the surface cools down, so you need to give time to equalize the temperature (condensation may appear);
It is necessary to degrease in personal protective equipment: rubber gloves, respirator, goggles.

Degreasing is a mandatory step in the preparation of the surface for painting, and it must be carried out before applying each next layer.

Stage 4. Putty

If the car has chips or deep scratches, before painting the car, you will have to use a putty to level the surface. The putty is the thickest layer in the system and therefore influences the final shape of the car body. When filling, it is necessary to pay special attention to the choice of polyester filler and to the preparation of the surface for the filler.

Surface preparation for putty

Sanding before applying the filler	Sand to metal - P120 wheels, then smooth out the boundary edges P220
Shaping the putty	P120-P180 sheets on grinding with dust extraction
Preparation for a leveling soil	Wheels P220 - P280 - machining
Preparing a new panel for wet-on-wet ground	Wheels P320 - machining
Sanding before painting	P1000 waterproof sanding paper - hand cut Dry sanding paper P320 - P500 - machined

Improper preparation of the surface for the putty can subsequently lead to a defect in the paintwork such as delineation... This can be avoided by observing the following technology:

Grind the degreased surface to metal;
Smoothen the edges of the spot of the repair area thinner.

The choice of putty

When choosing a filler, you should pay attention to the nature of the damage (size and depth of dents, hole in the body panel, etc.) and the type of surface (steel, galvanized steel or aluminum).

Basic rules for applying putty

Apply the filler only to bare metal or epoxy primer.
Observe the correct proportions when mixing with the hardener (max. 3% hardener) - otherwise, excess hardener will leave molecules that have not reacted with the filler.
Mix very thoroughly with the hardener.
Never sand the filler "wet", as it is hygroscopic.
Application of primers.

Hardeners

The hardener primarily affects the rate of hardening of the product. Therefore, the decisive factor when choosing a hardener will be the drying time of the product. There are basically three types of hardeners - slow, standard and fast. It is very important to maintain the correct proportions when mixing any paint and varnish product with a hardener:

If there is a lack of hardener, hardening (polymerization) will not occur completely.
If there is an excess of hardener, the hardener molecules may react with another substrate. For example, with water (moisture), causing a loss of gloss in the paintwork. Remember that hardeners are the most sensitive of all products to moisture and cold temperatures. Therefore, never leave the jar with the hardener open and observe the temperature conditions for storage and transportation of hardeners.

Stage 5. Grinding

Before painting a car, any paintwork should be applied to a well-degreased and sanded surface. By sanding, we make the surface "roughened". The many thousands of small scratches resulting from sanding increase the surface area and this ensures optimum adhesion of the coating to the substrate.

The time spent on surface grinding takes more than 50% of the total repair time. For this reason, this part of the job should be as efficient as possible.

When carrying out grinding work, you must pay attention to the following points:

Choice of type of grinding: dry or wet, hand or mechanical.
Selecting the appropriate grinder depending on the type of work performed: orbital, eccentric or surface grinding.
Selection of abrasive material and grinding steps.

Is it possible to do without sanding a car before painting?

We've already said that a perfect sanding process guarantees half the success of all paint jobs. During sanding, all irregularities are removed and a risk is created for better adhesion of each new layer of material to the previous one. Let us list the main points according to which the grinding stage should in no case be skipped and why it is needed:

To improve adhesion of the surface with subsequent applied materials
To create the desired shape and surface
To remove old coating

Dry or wet sanding

Dry grinding is the most advanced and promising and has a number of advantages over wet grinding:

Save time
Saving material
Eliminate the possibility of corrosion
Elimination of absorption and saturation of processed materials with water
There is no need to wait for the complete evaporation of water
Less harmful to health (in the version with dust extraction)
More diverse range of equipment for mechanical dry grinding
Significantly wider range of dry abrasives
For a high-quality repair, it is necessary to use high-quality abrasive materials.

Choice of grinding steps

Do not sand polyester materials (putties) with water. Sanding of this type is allowed only during the stage of leveling soil processing.
When sanding, the correct steps must be taken to reduce the grain size of abrasive materials (each step in reducing the grain size should not exceed 100 units).
The abrasive material must be marked with an international standard, which indicates the quality and uniformity of the grain.
Border zones should overlap.

Stage 6. Padding

Primers provide protection against corrosion, level the surface and create good adhesion between the substrate and the topcoat. They come in etching and acrylic primers.

Purpose of primary soils:

Corrosion protection.
Ensuring adhesion of the surface and the base of the subsequent coating.

Purpose of filler primers:

Filling abrasive scratches, irregularities, leveling the surface.
The basis for the subsequent application of paintwork.

How to work with soils correctly?

Use a straight edge when mixing.
Stir the soil thoroughly before diluting.
If the primer is tinted, then paint is first added, and then the hardener and solvent are added to the resulting volume in the appropriate proportion.
Do not try to extend the pot life of the product by adding a solvent.
Apply layers correctly - inside the stain to avoid overdusting.
Observe the correct drying intervals between coats and do not speed up the drying time between coats by blowing - the solvent is locked with a foil and “boiling” occurs.
Use either a dry or aerosol developer before sanding.
Never use primers beyond the stated mixing pot life.
Do not glue too close to the primer area.
Make sure that the soil is completely hardened (risk of formation deep scratches during grinding and subsidence).

Stage 7. Base / enamel application

When the preparation of the surface for painting is completed, you can proceed directly to painting the car. In fact, this step will take you much less time than the ones described above.

In the overall design of a car, the most expensive and at the same time vulnerable is the body. In case of road accidents, even minor ones, its individual parts and details most often suffer. The simplest damage to the paint of external surfaces can occur when driving through the forest or due to poor quality work at the manufacturer. At the same time, the technology of body repair is so developed that it can be done not only with the help of specialists in the service station, but also in a private garage.

The design of such a part of a modern passenger car as a body, on cars of different classes, is similar in its main elements, however, there are some differences that primarily affect the rigidity of the car body. Most SUVs have a frame body, crossovers and some cars are equipped with subframes, most cars have a rigid monocoque body.

These features are important when it becomes necessary to repair the car body. The main bodywork elements are:

roof;
the base, which is the floor of the machine;
front, middle and rear pillars;
front shield separating the engine compartment from the passenger compartment;
mudguard;
trunk panel;
central tunnel;
wings - front and rear;
doors.

The power structure of the body includes:

front and rear side members;
non-removable thresholds;
front cross members and radiator;
crossbeam for internal combustion engine supports;
cross members under the front and rear seats;
window sill;
front and rear roof rails.

Some features of body repair

Do-it-yourself car body repair can be done if the damage to stamped surfaces or load-bearing structures is not severe and special technological equipment is not required to troubleshoot.

These works can be attributed to minor repairs, if only needed local repair body. That is, it requires the elimination of scratches or paint chips. You can also do complex repairs with your own hands when there are dents with paint damage, deformation of the body or subframe.

For any degree of damage, the first step is to diagnose the object of the upcoming work to determine the required amount of materials, the required tool and the estimated amount of labor. This should always be done - when scratches and corrosion are found, if you need to repair chips on the body or you need a serious straightening, as well as painting parts or the entire body.

Dents

Deformation of stamped bodywork elements can be repaired independently by the driver or the owner of the car. For these works, you need a workbench or a special table, a set of straightening tools, anvils and hoods. Before proceeding with the straightening of the damaged area, it is necessary to determine whether this can be done without further painting, or additional costs will be required for this. Read about the technology in a separate article.

Complicated car body repairs, when the geometry of the structure is violated or a serious deformation of the structural element of the frame, such as a spar, has occurred, it is better to entrust specialists.

If the straightening cannot be done without painting, then after straightening the metal, it is necessary to level the straightened surface with a putty. Apply the filler with a soft spatula. A primer is applied over the leveled part. This is a prerequisite for preventing corrosion and eliminating scratches when applying the filler inaccurately. The last step is painting the repaired part or the entire body.

Corrosion

Local body repair includes, among other things, the elimination of corrosion on individual elements. The thresholds are most susceptible to this due to scratches that form when stones hit while the car is moving and the lower parts of the fenders, where water and dirt constantly get.

Before removing areas of metal affected by corrosion, the entire part must be thoroughly cleaned from dirt. Determine the degree of rust damage to the metal and decide how to eliminate the corrosion. In case of slight rust, it is sufficient to treat it with an anti-corrosion compound that contains phosphoric acid. Then rinse the surface, degrease and apply primer.

Painting the part completes the process, but if the damage from rust is significant, then you need to cut out the damaged area and put a patch of quality metal.

Chips and scratches

During the operation of the car, especially on Russian roads, scratches of different depths and other damage to the paintwork cannot be avoided. - these are the simplest types of bodywork. In order to remove these minor damage, it is often enough to polish the damaged area.

To eliminate deeper scratches, you must thoroughly rinse the desired area, then wipe it with white spirit and treat it with a special automotive putty.

The final stage will be priming and painting the desired surface.In cases where the number and depth of scratches in a particular area are large enough, it is required to polish this surface using a special machine.

Further processing of this area also begins with putty and primer.