In detail: do-it-yourself truck body repair from a real master for the site my.housecope.com.
Like any other automobile, trucks also require periodic repairs. However, the design of trucks is different from cars. Consequently, their repair also takes place in a slightly different way.
It is better to entrust the repair of heavy cars to professionals. Car workshop specialists will repair the car as soon as possible. After all, a truck is used by owners most often as a means of earning money. Therefore, even a short-term downtime brings very large losses.
The frame structure is inherent in both domestic trucks and foreign ones. Repair of all trucks consists of two stages:
restoration of cabins;
restoration of frames.
This division applies to any frame technology. According to this scheme, buses, light frame cars and heavy trucks are repaired. And every stage is important. When restoring trucks, it is imperative to take into account their considerable weight, as well as overall dimensions. All units of such cars are heavy. In addition, an important feature of trucks is the presence of a frame in their base.
For the repair of trucks, slipways are necessarily used. This allows work to be carried out with high precision. When the bodywork process is over, the geometry of the frame and body is carefully checked. At the final stage, the repaired car parts undergo anti-corrosion treatment, as well as painting inside special cameras.
Body repair of trucks in a car service consists of the following stages:
a preliminary inspection of the machine is done;
the geometric components of the car body are verified;
paint is removed from machine parts, places damaged by rust are well cleaned;
parts are being repaired that can be easily removed from the car;
the restoration of non-removable units, assemblies is carried out;
parts made of plastic and other non-metallic materials are being updated;
the frames of trucks are being restored;
the bodywork process of "resuscitation" of the car is completed with painting and anti-corrosion works.
Video (click to play).
Specialists carry out high-quality filling of damaged surfaces of machines. They also make a primer. The paint is selected especially carefully, because its color should correspond to that in which the car being repaired is painted. When covering the machine with paints and varnishes, the dye must be applied in several layers.
The body process of restoring cars also involves straightening, welding, and grinding. So, for example, to restore radiators and cast titanium, aluminum, copper disks, the argon welding method is used at car services. It provides increased bond strength. Consequently, the performed repairs guarantee high reliability of units and parts during operation.
The argon welding method allows you to save significant money on the purchase of new parts, since it perfectly restores damaged ones!
The most difficult and laborious is the body repair of very large trucks. Also, work on the restoration of buses is difficult due to the bulkiness of these machines. Large trucks and buses are difficult to paint because the spray booth is limited in size.
During repair and restoration work, if necessary, the damaged glass is replaced. They are either glued into the structure of the machine, or inserted into special rubber seals. After replacing the windshield, it is advisable to change the wiper blades.
You can read about car body welding here.
A frame in a car is called a power frame, which acts as the basis for fastening all
body parts, engine, gearbox, drives, etc. It is usually necessary to resort to such technology as welding a frame with minor deformations of this part. For example, if cracks, chips, folds have formed, then in this case, it will be advisable to cook the frame. However, the welding technology should be strictly observed, because not only the quality of the frame will depend on this, but also in the future the safety of using the car.
Very often, trucks, for example KAMAZ, which transport large loads, can fail right on the highway. In order to prevent the occurrence of such an unpleasant situation, you should constantly monitor the state of the frame and make timely repairs to this part.
In order for the connection to be strong and reliable during the welding of the truck frame, a number of rules and requirements must be observed.
The first thing worth noting is the need to ensure that the metal does not overheat in the area where the seam is formed. It is necessary to cook the seam in small pieces, the length of which does not exceed 5 mm.
Be sure to wait a while until the weld has cooled down.
Next, you need to process the edges. This is done by means of a plasma cutter or grinder, because this is the most suitable option for cutting metal.
When welding the frame, make sure that the transitions from the secondary metal to the main metal are as smooth as possible. Be careful not to create undercuts, as it is this defect that will cause the frame to crack. In addition, the root must be boiled along its entire length, otherwise the whole process will be meaningless.
Considering the fact that it is quite difficult to work with many trucks, which are not very large in size, and the frame is very often prone to breakage, regardless of the quality of the seam, there is only one way out - you need to strengthen the place of the breakdown. A channel and a bolted connection are suitable for this.
Before proceeding directly to the welding process, the part should be well prepared. It is important to correctly identify the damage, for this it is necessary to remove all body elements and inspect the affected area. The place where the crack ends must be drilled out. This will help prevent damage from developing.
Advice! Use drills with a diameter of 5 mm.
Such welding works are performed with a semiautomatic device.
Learn more about the welding process. As already noted, the welding process is carried out in several passes.
At the first pass of the burner - the root is boiled. Prooking is carried out with electrodes, which are a wire with a thickness of 1.2 mm with the Sv08 index. Welding work is carried out under the influence of a current of 100 A. On the second and third pass, the current indicator should be 110 A with the same welding wire, while the beads should be as thin as possible and overlap each other. On the fourth pass, the current increases to 120 A.
It is important that cooking is carried out without interrupting the arc. This is the only way you can get the most even and high-quality seam.
All seams after the end of welding must be properly processed. The metal must be protected from negative environmental influences. The connection area must be washed, then sandblasted, degreased, primed and painted.
In conclusion, it should be noted that welding a truck frame is a process that requires concentration and care. In order for the seam to be as strong and high-quality as possible, the welder must have some work experience. Since the frame is an important part on which the safety of driving depends. Do not forget about safety and when welding, be sure to wear special protective clothing.If you follow all the rules and requirements, then in the end you will get the highest quality connection.
Damage to the wagon requires a fairly serious repair, and often a simple scratch is not enough here. Traffic accidents involving trucks or overloading a trailer often entail damage that requires a major restoration of equipment
Major damage
The damage received by a truck can be of different nature, but the main blow falls on the body. As a result of an accident, dents, scratches, tears, fractures and distortions are formed on structural elements.
Such damage does not always disrupt the operation of the transport, and most truck owners believe that if the frame is bent a little, nothing terrible will happen, only the appearance has deteriorated.
In fact, in the course of an accident, damage can be obtained, which will only make itself felt after a while. As a result, an accident can:
The axle of the truck will move.
Increase fuel consumption.
Accelerate tire wear.
Stop closing the door during the geometric deformation of the body.
An accident can cause disturbances in the internal devices of the equipment, which will lead to a malfunction at any time. This can happen while parking or driving on a freeway.
As a result, the owner of a freight transport has two solutions: to restore the truck on his own or to order a body repair in a specialized car service.
Important! Even after a serious accident or other damage, you can restore the iron horse on your own. But you need to know a number of rules and nuances so as not to aggravate the situation.
How to carry out body repairs?
The recovery of the truck takes place in stages. Repairs are carried out as follows:
The cab is dismantled from the frame and installed on the slipway. The repair slip has attachment points as on the frame and allows the cab to be returned to its factory settings by leveling out certain bends.
Diagnostics is being carried out. The cabin is inspected and the places of damage are studied.
Straightening, metal. Dents to be repaired are straightened using a pneumohydraulic station. Instead of flattening, you can cut a piece of metal and replace it with a new one. But it should be borne in mind that it is easier to return the geometric shape to the truck on factory metal.
The necessary elements are cut off. If you can't get around without a grinder, then the cut must be done carefully, not along the weld.
Weldable, metal. Welding should take place in a carbonic environment in a spot-like manner to avoid overheating of the iron.
The cab is being prepared for painting. Weld seams, old enamel are cleaned. Then the surface is removed with a putty. The procedure must be carried out slowly. The durability of the repair and appearance will depend on how carefully the body is prepared for painting.
The cabin is being painted. It is necessary to carefully select enamel, paint and paint.
Leave the upper body to dry and move on to the frame. Despite its sturdy construction, the powerful iron cannot withstand the pressure of the truck, which is why it starts to be driven or twisted by a screw.
To straighten the frame, use induction heating or a gas burner. However, using a burner weakens the iron and makes it softer. To return the frame to its factory parameters, a special slipway is used, on which deviations from the norm are monitored. After that, the heated metal is directed in the required direction.
After repairing the frame, we assemble the body and look at the result of the work.
Pros and cons of DIY body repair
Have you decided to repair the damage yourself? Great, but first learn the main pros and cons of doing this.
The advantages of self-repair are:
Saving money. Restoring equipment on your own does not require a lot of funds. You can always find components several times cheaper than those offered in a car service.
Quality. If you want to do well, do it yourself. Each driver takes care of his car like a child, so he will always be careful about his work. You can choose parts, painting and other materials yourself.
Despite two significant advantages, self-repair has a number of disadvantages. The main disadvantages are:
The need for special equipment. The whole procedure for restoring the body and the trailer requires a slipway, a rack, a grinder, a welding machine, an induction heater and a number of other devices.
Time costs. If you do not have sufficient experience in working with metal and repairing trucks, the restoration procedure can take more than one day.
Difficulty in implementation. To get a good result, you need to have skills in handling tools and know the basic properties of metals. For example, if the frame overheats, the structure may weaken. Outwardly, you will be able to return the geometric shape, but with a small impact, the metal may not withstand and cause even more damage to the rest of the structure.
It is recommended to repair trucks on your own only if you have certain skills and special equipment. In another case, you should not risk it, because you can spend time and money, but in the end you still have to contact the masters of their craft.
Trust the professionals
Special equipment and a staff of professionals, each of whom knows his own business, is what is needed for a quality repair. Do you want to receive a truck after restoration, as from the factory? Freight car service "Motion Technology" will provide you with such an opportunity. The main advantages of the service:
Professional equipment. Stands, induction heating, slipways and other accessories from renowned manufacturers.
Experienced staff. Behind the shoulders of nude craftsmen, hundreds of repairs have been completed. They know what is best for your truck in a given situation.
Quality materials. Paint, enamel, putty - the high quality of these materials will ensure the preservation of the exterior of the body for a long time.
It is not worth risking a technique that costs a fortune. Spend hundreds of times less and get a well-repaired truck within a few days. The full list of services can be found on the company's website.
Message Ivanych »12 Aug 2011, 21:26
Message Ermak »13 Aug 2011, 20:44
Message Ivanych »13 Aug 2011, 21:08
Message Ivanych »16 Aug 2011, 20:52
Message Volodia3281 »16 Aug 2011, 23:12
Message DIESEL »17 Aug 2011, 19:57
Ivan why plywood and not a 40a or 50a board.
Added after 1 minute 6 seconds: And where did you buy such eyebrows? What price.
Added after 3 minutes 26 seconds: Himself, too, will have to rework the body. Until now, the native floor is made of mahogany, although it is already full of holes and weak. Hold on until the fall, so as not to lose work yet)))
Message Ivanych »17 Aug 2011, 20:10
The board is very poorly laid out, dries up. and loaders always load from the side, it turns out against the grain. And this is special plywood. she now spreads on all trucks and on Koreans and on KAMAZ trucks. I'll try, but it will definitely serve for three years. And the eyebrows are my relatives, as they stood on the old Japanese wooden one, they remained, without them I can no longer imagine fasteners.
Added after 9 minutes 37 seconds: Another photo is below. oak interlayer between body and frame! I had to pull the body to the frame with ten stepladders, on a wooden one there were six
Message DIESEL »17 Aug 2011, 20:16
All clear. It's just that he changed his native floor on the Hinka to a 40k board and served for two years without any jambs. The partner has been driving the 40ke for four years and is also good. Chipped and cracked, of course. But this is all from concrete and iron))) You have to carry a lot of things that can damage the body and the floor.Well, plywood is most likely for intercity cars. Everything is there on flights or so packed that horseradish crumbles and damage the floor))) Something like this IMHO.
Added after 3 minutes 23 seconds: The spacer between the metal is a must, it is impossible without it. There are also rivets in places in front of the frame under the body in the place where the frame is reinforced under the CMU. Or wooden or conveyor belt)))
The restoration of the skeleton of trucks and other large-sized equipment has its own differences. Initially, this concerns the dimensions and weight of both the cars themselves and their individual mechanisms. The second difference between the repair of the body of trucks, in contrast to the restoration of the metal frame of "cars", implies the obligatory presence of a frame on trucks. We will learn more about the features of these types of work from the article.
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The main difference between the repair of a truck and a "passenger car" is the design. Accordingly, the repair is carried out in a different way. It is better to entrust the repair of the truck to specialists. They, as a rule, guarantee not only the high quality of work, but also the result in the shortest possible time. This is only a plus for the owners, who in most cases use a truck as a means of earning money, and even the shortest downtime brings big losses.
So, in view of the fact that almost all trucks are equipped with a frame system, their repair can be carried out according to two scenarios.
Frame restoration.
Restoring the booth.
This classification can apply not only to trucks, but also to frame cars, for example, such as UAZ.
A slipway is an indispensable tool if a truck body repair is carried out. It is this professional equipment that is able to ensure high accuracy of the geometric component of the body or frame during the restoration process.
The final stage of body repair involves anticorrosive treatment and painting of the car in special closed boxes.
The cost of restoration work depends on various components. As a rule, the price is determined by a specialist after examining the damage.
As well as car body repair, these restoration works are also carried out in accordance with the rules and consistently. The skeleton of a car can be tidied up even if the car is involved in a major accident.
Consider the main stages of restoration work on a truck body:
First, a qualified inspection is carried out;
The geometry of the body is diagnosed;
Parts are cleaned of traces of rust and paintwork;
Easily removable body elements are restored;
Straightening, straightening and bringing to the original geometry of the body elements is carried out;
The frame is being repaired;
Painting and anticorrosive work is being carried out.
As for welding, argon welding is used for non-ferrous body elements. The latter provides a strong and reliable connection of body elements. Argon arc welding is also called universal, because it can solve a wide range of tasks facing a body repair specialist. This type of welding is considered super modern, it allows not only to repair the components of the body with high quality, but also to save finances for the purchase of new parts.
The most labor-intensive is considered to be in the body repair of trucks, the restoration of the frame of the bus. This complexity is explained by the large dimensions of the latter. On the other hand, if a garage or service is equipped with a modern-type painting camera, then cars up to 14-15 meters long can be restored in such a box.
Recently, on the roads of our country, you can find a considerable number of Japanese trucks. Isuzu and Nissan are finding their recognition on Russian roads more and more often.Regardless of the area of application, the "Japanese" are always at their best, because the cars from the Land of the Rising Sun are powerful, fast and have excellent traction characteristics. All this, including being equipped with advanced and reliable electronic assistants, makes these trucks attractive in our country and around the world.
The popularity of Japanese trucks can be explained, in particular, by the fact that Isuzu is assembled in our country, and Nissan supplies light Spanish-assembled Cabstar trucks to Russia at an affordable cost. Nissan Kabstar, among other things, is incredibly economical, has a high payload and ease of use and comfort.
Unfortunately, in the course of active operation, the body of even the highest quality car falls into disrepair. It "gets old", its parts get rusty, deformed, and so on.
If in the recent past all body problems were eliminated by drivers mainly with their own hands, today the companies that carry out body repairs are highly valued and are in great demand. If earlier domestically produced trucks were in vogue, parts for which could even be produced independently, then a modern, improved and powerful truck already requires more qualified service.
Repair of bodies of Japanese cars requires different approaches. As with the maintenance of any large-sized equipment, the repair of the Isuzu and Nissan skeletons has its own nuances.
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As for the kerchiefs and linings - their excessive thickness is also not good.
A truck frame is by no means a rigid structure, but rather an elastic element that acts in bending and, even more so, in torsion.
Therefore, thick linings change the properties of the frame and cause its destruction in other (sometimes in very unexpected) places. I consider it optimal to use metal with a thickness in the region of +/- 1 mm of the thickness of the frame metal. Thicker metal (up to 140-180% of the base metal) is used when lengthening frames with bolt-on central inserts, while the length of the overlap of the frame fragment and insert is at least 3.5. 4 frame heights. With significant elongation, additional overlays for the insert are desirable.
In terms of shape, rhombic with truncated corners, trapezoidal and, in some cases, triangular overlays are preferred. In any case, care should be taken to avoid transverse (vertical in relation to the frame) seams (except for the ends of the frame) and stress concentrators (sharp corners of the welds).
Similar Things also apply to platforms, bodies, sides and other superstructures.
Now about the bolts. When something is attached to the frame, the main reason for the failure of the fasteners is not at all the shearing of the bolts, but the fact that the bolts fray due to "looseness" in the holes of an unacceptably large diameter. Therefore, there is no point in using M16 to fix the box (extra large holes only weaken the frame). Much better - 8-12 bolts М12-М10, but into holes of exact diameter (no more than +0.1. + 0.2mm)
My opinion is that the diameter of the fasteners to the frame should be no more than 2.5 (at least 3) thicknesses of the frame metal (exceptions are specially prepared places reinforced with pads for redistribution of loads, in this case - up to four to five times the thickness)
It is known that bodywork is the most common and labor-intensive in car repair. Most often, they use purely copper techniques, leveling the disfigured steel shell with mallets, rubber or polyurethane hammers, and finishing operations by soldering tin or lead.
I can say that I have long abandoned this technology in favor of the technology, which has been worked out on dozens of dents and holes, using epoxy resin, filler and fiberglass.First of all, the wing (as well as any other element of the machine shell) is straightened, and it is not at all necessary to bring its outer surface to an ideal state.
The main thing is that there is no metal protruding beyond the surface, which should result from the repair. On the contrary - in many cases, it is better to deliberately lower the surface so that an epoxy-fiberglass patch of a noticeable thickness can be applied to it.
If the wing has not only dents, but also tears or thoroughly rusted places, then this is not a problem either. It is only necessary to cut out the eaten away by corrosion and carefully clean out the areas affected by rust. In doing so, I recommend using a rust converter and a steel brush. More than once I have heard from motorists talk that under the "epoxy" metal actively rusts.
Indeed, many have observed such an effect, but it is not "epoxy" that is to blame for this, but ignorance of the technology of working with this material. To ensure reliable contact of the epoxy binder - epoxy putty or the actual epoxy resin in combination with fiberglass - the following technology must be adhered to.
To begin with, the part of the metal shell to be repaired is thoroughly cleaned of old paint and soil, treated with a rust converter, and then sanded to shine with sandpaper or Durex abrasive wheels. Immediately, within a few minutes after cleaning, the surface is coated with an epoxy resin composition with a coupler inserted into it (the usual ratio is from 1: 8 to 1:10, although some types of epoxy resins are diluted in different ratios of resin and hardener, so before use specify the preparation method according to the label or the inscription on the box) with the addition of acetone or solvent No. 646 - until the density of the usual nitro paint.
After application, the solvent or acetone evaporates. And on the surface of the metal remains a film of a relatively slowly polymerizing resin, which protects the metal from oxidation. There is no need to wait for the resin to finally cure. Almost immediately, you can start filling in irregularities or holes. Of course, it is better to prepare glass cloth rags and some resin in advance.
I do not advise to dilute the resin at once for the entire volume of work - it is better to do it in portions of 100. 200 ml: in large volumes "epoxy" is prone to self-heating and spontaneous polymerization. And one more thing: sleep the work is supposed to be long, put a container with prepared resin and a bowl with ice or snow - this will delay polymerization for several hours.
The repair begins with the fact that the restored place is coated with resin (not this time with the usual one, without acetone), after which a piece of fiberglass is applied, and it is once again coated with resin on top. The best way to apply the resin is to use a stiff brush. Then you can act in two ways.
The first one is filling the depressed places with rags of the same fiberglass, smearing it with resin until the thickness of the layer is brought to the contour (or rather, slightly exceeding it), which must be obtained after repair. And the second method is to apply epoxy putty over the first layer of fiberglass, consisting of epoxy and any dusty filler - tooth powder, talcum powder, cement, etc.
After applying the putty (the criterion is still the same - its solder should only protrude slightly above the future surface contour, which is easy to control with a flexible rail or a template cut out of plywood in advance | the surface is sealed with another piece of fiberglass. If the shell had breaks, it makes sense from its inner side also glue several layers of fiberglass in order to get a kind of lock preventing the patch from peeling off.
Further, for both the first and second methods, the following finishing operation can be recommended.On top of the epoxy composition, polyethylene films are applied to a cut, after which the still plastic epoxy putty or glass cloth molded to the metal should be carefully smoothed in accordance with the shape of the wing or other part of the machine shell.
In this case, you can use a piece of laminated plastic or sheet metal (they press the patch with them), rubber spatulas, and simply with your hands - preferably in cloth gloves. Excess resin is easily squeezed out and removed during the polymerization process.
If you have not "overdone" the hardener, you will have at least a couple of hours to calmly bring the surface under the film to perfect condition. Finally, the film is stretched over the surface of the body part being repaired and secured with tape or vinyl tape. The next day, the polyethylene protective film will easily separate from the resin surface - and you will see a glossy, polished surface that practically does not require any additional processing.
(
A typical dent in a car fender.
Restoration of cladding with glass cloth and epoxy resin or epoxy putty: A - with resin and glass cloth, B - with glass cloth and epoxy putty. Letters in the figure indicate: K - wing, C - fiberglass, W - putty.
Finishing the surface with a polyethylene film: 1 - shaping the film and smoothing the surface with trowels and hands 2 finished restored wing. The letters in the figure show: E - epoxy composition (fiberglass or fiberglass in combination with epoxy resin), K - wing, A - final wing surface, P - polyethylene film.
I had to deal with welding of the KamAZ frame. After a while, a crack appeared near the seam. I decided to reinforce the structure with a "rhombus" overlay, cut the edges and welded it in two passes. Six months later, the same problem - the frame cracked. What is the truck frame repair technology? A similar question about welding the axles of foreign cars semitrailers.
The manufacturer claims that the frame cannot be restored, but nevertheless, the workshops often successfully cope with this difficult task. Here are some secrets to welding a frame:
1. One of the main features of frame welding is cutting edges with a plasma cutting machine. 2. It is necessary to securely weld the root of the seam (if for some reason this stage cannot be completed, it is better not to undertake repairs) 3. Use filler material (welding wire) 08G2S (depends on frame material), 1.2 mm. Protective medium: a mixture of argon + carbon dioxide (20%). 4. Passage number 1: welding current 100A. The root bead is welded with short rollers across the groove from left to right to form a reverse bead. It is important to avoid overheating the steel. 5. Passage No. 2 and 3: welding current 110A. It is carried out as in step 4, but the rollers are thin and superimposed one on top of the other. 6. Passage number 4: increase the welding current to 120A. A roller over the entire groove width with an interception for the base metal of 1-2 mm. Several rollers - and the arc break. It is important not to overheat the base metal. 7. Final pass No. 5: the bead is cooked without breaking the arc, the interception on the base metal is 5 mm. 8. Vertical seams are welded from top to bottom. 9. An individual approach is important in each case. 10. The seam is even, convex.
An article about local repair of a car body - preparation, procedure, subtleties of work. At the end of the article - a video about car body repair.
There are many reasons that lead to the repair of one or another part of the body. These can be mechanical damage to the paintwork by road debris, the consequences of minor accidents, chemical damage due to improper use of reagents, and, finally, the manifestation of ordinary corrosion.
Of course, as a result of the listed damage, the car does not lose its technical characteristics, and therefore there is no reason to hand it over to scrap.Only the external aesthetics of the car suffers, and this problem is quite simple to solve. And if you repair everything with your own hands, then the economic benefits will be obvious.
Before local body repair, you need to wash the car well, and then diagnose for defects. This is necessary in order to know for sure which parts of the body need to be repaired, as well as what tools and equipment will be required for this.
The first step is to investigate the nature of the damage. For instance:
dents resulting from an accident, as well as from impacts of stones from under the wheels;
violation of the integrity of the paintwork: chips, cracks, scratches, etc.;
corrosion.
If this damage is mechanical and at the same time it is associated with a rupture of metal surfaces, or if it is a typical corrosion that has “eaten through” the metal through and through, then it would be reasonable to replace the damaged part with a new one. The same can be said about those damaged places in which the stiffeners suffered. But if the part cannot be replaced (the model is outdated), it can, in principle, be restored, but it will be much more difficult to do this than to replace it.
In addition, it is necessary to find those places that require correction of geometric deformation, and also note all minor damage that can be easily removed with a putty. As a result of such a defect analysis, you will know which body parts will require subsequent repair.
The most effective way to repair a damaged body part is to replace it. But if you nevertheless decided to repair the part, then in this case it will have to be dismantled. So let's start with dismantling.
Most of the body parts can be bolted or self-tapping, so they can be easily removed without welding. By the way, if the repaired part is installed already painted, it will be much better and easier.
However, there are parts that are assembled using spot welding. To dismantle them, use a special chisel and hammer. With these tools, a weld point is cut between the parts at the attachment point.
It is better to install the repaired part using special mastic, as a result of which the elements will connect to each other much more tightly and tightly. This will create additional waterproofing. It is advisable to do this with any method of connection, but if you use welding, you must keep the welding points clean.
No local body repair can do without putty. The fact is that, having repaired the damaged body parts, in any case you will have to go to the final cosmetics.
The first step is to close the deepest irregularities, the depth of which exceeds 1 mm. To do this, use a coarse filler. At the same time, do not forget that among the parts that make up the body there are parts that are subject to vibration and can deform from this.
When processing such parts, use a putty containing an aluminum filler. Fiberglass putty can be used for the rest of the parts.
To begin with, the places where you plan to apply the putty will have to be matted. This can be done with a medium-grit emery cloth for better adhesion to the surface.
The next stage is directly puttying. And this process should take no more than 20 minutes. In any case, most putties have this setting time. Therefore, in order to be in time, proceed as follows:
Dilute the filler according to the manufacturer's instructions. After that, mix the solution thoroughly enough so that the composition excludes air bubbles, has a measured color and the same consistency.
Start applying the solution to the surface with a spatula.At the same time, be extremely careful not to overestimate the required layer thickness. Therefore, it is better to apply thin layers in several steps to achieve the desired level. And if the surplus does appear, they must be removed immediately.
Allow the putty to harden.
Note: of course, it is impossible to immediately apply the putty so that later this surface does not require mechanical processing. Therefore, it will be very good if you come to a result that is as close to ideal as possible.
As already mentioned, mechanical processing of the putty surface in any case cannot be avoided. Therefore, wait until the composition has completely solidified, and then proceed to processing.
To do this, stock up on emery cloth and a wooden block. For a start, you can use a medium-grained skin, and try to pick up a block that is not very large, but fairly even.
The method of such processing is quite simple: wrap the block in "sandpaper" and begin to process the surface to be repaired with it. It is due to the even block that you can identify where it is necessary to remove excess putty, and where it needs to be added.
You can use an orbital sander besides the sandpaper-wrapped bar, but it takes care and a lot of experience to use it. And if there is no such experience, then it is better to sand it by hand, as described above - you will make fewer mistakes.
Despite the fact that this procedure is quite simple, rare specialists manage to do everything the first time. Therefore, after the first treatment, check the result and, if necessary, repeat everything again. Your ultimate goal is to keep the surface level and free of pits, bumps, or seams.
So, you have done the "blackest" work, the repaired surface already has a favorable appearance, and now there is little to do - to eliminate small defects. The problem is that sometimes it is even impossible to notice them with the naked eye, but after repair they will definitely show themselves.
And here you will need another, fine-grained putty, which is also called finishing. You apply it in the thinnest layer to those places that require it: scuffs, scratches, an excessive layer of coarse-grain putty.
The condition is the same as with the use of a coarse-grained putty - you need to have time to apply the composition before its initial hardening. After that, there is a stage of mechanical finishing, and fine-grained sandpaper is already used here, which is popularly called zero.
This work should also be done manually if there is no experience in using special tools. The necessary result of this procedure is the complete absence of irregularities, both visible and invisible, and tangibly tangible.
In this final step, sometimes it is possible to apply the putty in several layers, but in most cases one is enough.
Once you have done all this, the repair can be considered complete. All that remains is to paint the repaired areas and your car will look like new.