Do-it-yourself repair of through corrosion

In detail: do-it-yourself corrosion repair from a real master for the site my.housecope.com.

Actually a question on a photo. The problem is not only in an unaesthetic form, but also in the fact that the rear bumper began to fall off and the plastic protection fasteners fell out (inside the wing).
For some reason, only the rear fenders and rear door sills (on both sides) began to rust. In other places, even where there were scratches and rubbing, there is no rust.

The threshold is rusted through, the wing, it seems, is not yet through 🙂

The service said that "you can weld it, but not with them, since there is a gas tank pipe nearby."

Car Nissan Almera 1.6 (1999).
I would appreciate any advice and suggestions.

I can offer to do everything according to the mind for 20000r. with local painting
this is the New Year's Eve

but I don’t advise you to engage in sculpting, and the view will not be the same, and reliability is not up to par

“New Year's option” - I meant the price is more correct, of course, to buy arch repair kits and weld them
then professionally painted
it is not necessary to remove the tank for this, it is enough to disassemble the filler neck
it would be easier to describe the procedure in more detail with a live examination of the damage

This is exactly the option I offer you.

if you want for centuries - replace it with a piece from disassembly. A piece of threshold + wing arch (wing) will cost 3000-7000 rubles.

Replacement will cost us 7000r.,
repainting will cost us 4000r.

Finding a spare part is a matter of one day, we are ready to find it according to the car’s data: year of manufacture, modification

well, for 5 years - this is practically “for centuries” any “pope-mache” will not last 5 years,

but if you digest it - everything will be super like new

Buy and weld repair arches. They are not expensive.

Video (click to play).

The price of work for 1 wing = 3,500 rubles. (tin) + painting of the wing and opening = 7,500 rubles.

On an 11-year-old 2105, I did it as follows. Among other things, there was such a hole:

First, you need a warm garage (in winter). Now about the process.

1. With a drill with a nozzle in the form of a crowned metal brush, we completely remove the rust to approximately this type:

By the way, on the other side of the car it was more like your case, here is the result of cleaning:

2. Now we take fiberglass (some use nylon stockings, but I won’t recommend it), cut it out so that it repeats the contour of the cleaned “hole” with an allowance of 1-2 centimeters. The surfaces around the "hole" are degreased with alcohol.

3. We smear the fiberglass with special automotive epoxy glue (two-component smelly rubbish in cans), stick the holes in place, smooth them out. It is not necessary to immediately try to achieve the desired shape - the main thing is that the glued fabric is not "curved" outward from the original body profile.

4. After three hours, we look at the result. If the fabric is strongly concave, repeat the procedure over the pasted layer. The second layer will smooth out easily. When gluing the second layer, try to give the fabric such a profile that after applying a minimum of putty.

5. We are waiting for three hours until it dries. Then we take a two-component putty, we make a batch. Without thinking twice (otherwise it will freeze), we apply the mass with a spatula over the glued fiberglass in such a way as to recreate the original geometry of the repaired area. Along the edges of the fabric, you need to “come out” with putty on the metal so that the edges of the fabric are well visible.

6. The next day, we pick up a drill with a nozzle-circle, on which a delicate skin is fixed. We sand the surface in such a way that it becomes almost smooth and that the transition from putty to body metal becomes minimally noticeable (do not sand to fiberglass - it will only get worse).

7. We wipe and degrease the surface, apply a primer (using a can at a distance of 30-40 cm) in two layers. Between layers we take a break for 20 minutes. After a couple of hours after priming, we take a can of paint and apply this same paint to the repaired area.

motivation is wrong. I've never heard of a part being replaced with plastic.Only the whole detail.

If you think a little, it is quite obvious that the welded joint of two metal sheets is somewhat more reliable than gluing. even if it is a widely advertised poxypol. It seems to me that rivets will be stronger than epoxy / polyester glue.

I don’t know what special automotive resins are, I divide them into epoxy and polyester. The first ones seem to be stronger, the second ones seem to cure faster. Epoxy is typically advised to process within 24 hours of mixing. Polyester "gets up" an order of magnitude faster.

Further: "When gluing the second layer, try to give the fabric such a profile,"
You don't have to do that.
The fact is that when gluing fiberglass, the resin plays the role of only a binder, but not a shaping material. Therefore, there should be a minimum of resin, only for impregnating fiberglass (the last time I glued the bumper - for lack of fiberglass I used a paint bandage, a kind of air synthetics), but not for the formation of volume. Resin, in general, is a fragile substance in itself, therefore, in fiberglass, it is not so much the resin that "works" as the filler.

It makes sense before applying the first layer of "fiberglass" to bend the desired surface out of something, with a margin of several layers. For a piece of bumper, I simply bent it from the inside of a metal mesh from the nearest construction market. Grid with a square 5x5mm. And on it are several layers of the specified material impregnated with epoxy. After a day, you can grind (although the resin is fragile, but strong, it’s better to grind with a machine, I went “black” with a cleaning disk on a grinder. 🙂 and then bring it to zero with polyester putties. The first layer with fiberglass filler to cover large irregularities, and then aluminum or something like that.

but I agree with previous speakers that such a "repair" is expedient for sale. For yourself, it’s better, after all, to weld a patch. either by cutting out from the donor, or by adjusting the sheet pieces with the subsequent removal of the surface of the spatulas. With non-crooked hands, it will be both more reliable and durable than epoxy patches.

Yes, by the way, there is another "home option": cut out the damaged pieces, but do not weld the patches, but solder them.

and some photos:
about the form for gluing: (the screws are subsequently unscrewed, traces of them are plastered)

about patches: on the left in the process (what was cleaned was practically absent, traces of seams are visible), on the right is the result (ignore the white balance, the color is black. 🙂

Image - Do-it-yourself repair of through corrosion

a year and a half has passed, until (ugh * 3) there are no holes.

PS thresholds and boxes were completely amputated. 🙂

ps. about the gas tank. hike in the service just did not want to mess around. On the Volga, they made a rear fender and fender liner in the service, the gas tank was corny removed for the time of welding, and the pipes were taken aside.

Look for a less snickering service that will remove the gas tank and find a donor at the disassembly.

Well, I'll take it, because. did only "for myself" once without experience and knowledge.

Since then, by the way, the car has been going through the second winter (now with a new owner) and these places do not give themselves away.

How to get rid of rust on a car body is a question that worries most owners of used cars. There are not many options, go to a service station, or deal with the problem yourself. Many do not know how to deal with rust on a car body, so they often simply cover it with paint, but this method does not save for long, but rust is not fatal, so consider ways to get rid of it.

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Of course, the most correct and cardinal solution in the fight against corrosion would be to replace the entire part as a whole, however:

It happens that such a part cannot be obtained, or its cost exceeds reasonable limits, but you always want to save money;
Therefore, now we will figure out how to eliminate rust on a car body with our own hands;
There are several ways, and all of them are quite laborious;
Modern cars have galvanized bodies, at least most;
This prevents corrosion from developing, however, with deep scratches, creases and chips, the protective zinc layer is damaged;
How do you make sure your car body is galvanized?
It is enough to study the passport data of your car;
Or very carefully scrape off the paint from an inconspicuous area of \u200b\u200bthe body, not forgetting to paint it over afterwards;
For a car, a stainless steel body is not produced, most likely the matter is in the cost of production, so the problem of rust remains relevant;
It is necessary to observe safety measures, use goggles and rubber gloves, when performing body work, to avoid contact with the body of chemicals.

If the body is affected by rust in several places, it is necessary to thoroughly wash these places with car shampoo before starting work, then:

After the case has dried, all problem areas must be treated with coarse-grained sandpaper, or use a metal brush;
It is not recommended to use a grinder, because the cleaning discs remove a layer of metal;
Only plastic-soled discs are suitable for this procedure;
With an abrasive wheel mounted on a drill, go through problem areas.

If the corrosion is deep, and even small holes have appeared, then they act in the following way:

With the help of a cone brush (more rigid is recommended) put on a drill, rust is removed from the car body

Attention: The use of abrasive wheels and a grinder is not allowed - you will simply burn the metal, after such a cleaning it will rot very quickly.

After stripping, you can confidently assess how deeply corrosion has penetrated. The cleaned place is blown with air from the compressor, then you need to put a spotlight or lantern behind the part;
If the body part is non-removable, then you should try to stick a light source in the back;
In places where holes appeared, luminous dots will be visible when the external lighting is turned off;

Instructions on how to stop the corrosion of the car body are as follows:

The easiest way is to solder holes with ordinary tin solder;
To do this, you need a hammer soldering iron, soldering acid (rosin is not suitable here), solder brand POS-61, a building hair dryer can still be useful to warm up the repair place when the power of the soldering iron is not enough;
Get a rust converter, you can't do without it.

Attention: Before starting work with a new soldering iron, you should irrigate the tip (its working surface).

Before starting work, the repair site with through corrosion should be cleaned of rust residues;
Because solder will not stick to a rusty surface;
The most important thing is not to be lazy when you are too lazy to mess around, then go back to the beginning, where it is recommended to purchase a new part;
To remove the remnants of rye, you will need a pointed file, or a piece of a hacksaw blade, or a knife with a sharp blade and abrasive skin;
Coarse sandpaper, (grain P60-80) goes through the center of rust (if not brushed), so the surface layer is removed;
Then you should pick out the rust from the metal, which has already eaten;
To make the places clearly visible, you need to apply a rust converter with a brush and wait a couple of minutes;
The rust will darken and become clearly visible on bare metal.
at this stage, pointed objects will come in handy to pick out rotten metal;
The process is the most dreary and time-consuming;
You should constantly apply a rust converter to these places with a brush;
In this way, you wash off the rust that you have already picked out and see where you need to make extra effort;
After the place is cleaned, you can begin to service it;

Attention: When the diameter of through holes exceeds 2-3 millimeters, it will no longer be possible to fill them with solder, this method is suitable when through corrosion forms in the form of a fine mesh.

Apply soldering acid to the surface before it dries, you need to apply tin solder with a heated soldering iron over the entire cleaned surface, where corrosion holes already exist and may occur
To better stick tin solder, constantly grease the evaporating acid
When the body metal is thick and the power of the hammer soldering iron is not enough to heat the tin, then use an industrial hair dryer or a second soldering iron

Tip: Soldering should be done in the open air or in a ventilated room (or in a room with forced exhaust), since the evaporated acid is very harmful to the respiratory tract, and its smell is not pleasant.

Repair of corrosive damage to the body does not tolerate hack-work, the price of careless work is that the body will rust again and very quickly;
After completing the work, check again with the light if there are still through holes;
After the repair place is tinned and the corrosion centers are soldered, the treated surfaces should be cleaned of acid and the converter that could remain;
As a rule, they are washed with water, or with a mixture of gasoline and alcohol;
In order to increase the service life of the repaired body part, it is important to properly protect it from contact with the atmosphere;
On the tinned place of this body part, using a paint sprayer, apply acid primer, then, on top of it, acrylic primer, only after that you can putty the surface;

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Important: Putty cannot be put on top of acid soil, therefore acrylic primer is placed.

If suddenly, when sanding the putty, you have rubbing to the metal - there is nothing to worry about, just blow it with acid soil again and cover the exposed places with acrylic;
When you finish restoring a rusty car body, you should definitely protect the back of that repair spot as well;
Condition required! Otherwise, all the work done will go down the drain;
There are many ways to protect against corrosion, the main thing is to block the access of moisture and air to the protected place;
The first option is to prime the reverse side with acid and acrylic primers;
The second option is to apply a layer of good sealant, mastic or fill with Movil;
The choice of option will depend on the ease of access to the treated surface;
If you can’t crawl with a sprayer, try applying primer with a brush, then cover with Movil, for reliability, or a similar agent;
Now it is clear to you how to restore the car body from rust with small holes;

When a hole has already formed in the body, putty or soldering is indispensable here:

The easiest way here is to make and install a patch;
Of course, this method is suitable for holes with a diameter of no more than 5-7 centimeters, when the hole is larger, it is definitely necessary to replace the body element, or welding;
How to get rid of rust on a car body if holes have already appeared ?;
First, the damage site should be thoroughly washed, then cleaned, cleaned of rust, as described above;
After that, a patch is cut out a little larger than a hole, from thin metal, a tin can is suitable;

Now you need the same hammer soldering iron, with its help you have to tin the surfaces on the outside of the hole and the edge of the finished patch with tin;
As a flux, soldering acid, or its analogue, is used;
At the end, it will be necessary to solder the patch with a continuous seam, then the patch with a hammer must be precipitated;
Clean the protruding edges with coarse-grained sandpaper;
After that, cover the defective place with putty, primer and paint;
Body repair after rust can be done by welding;

The patch is carbon dioxide welded to the body, however, for this you will need a welding machine (or a welder with a machine), plus the skills of a welder;
Further processing as with the previous patch, cleaning the primer, putty, sanding the putty and painting;
Don't forget about the processing of the reverse side.

We wish you success in body work!

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The car body is the most expensive part of it. But the modern auto industry offers car bodies of such quality that the “first swallows” of decay can be encountered already during the first two years of operation.

One of the easiest ways to solve a problem, or rather, slow down its development, is to contact a specialized car service. There, they will perform an expensive cycle of removing through rust, from welding to applying a paint and varnish coating.

Is it possible to repair the body with your own hands, the rust that “ate” to the hole? A variety of tools and materials offered in car dealerships allows you to perform several ways to get rid of perforated body rust. They will cost less than professional repairs and take relatively little time.

Through corrosion of the body is completely eliminated in only one way - the complete replacement of the affected part. But this method is appropriate only in cases where the size of the affected area is more than 10 cm in diameter. Experienced body repair masters believe that with the right approach and the use of special materials, holes up to 8-10 cm in size are repaired.

To perform such work, you will not need special expensive tools, but minimal manual skills will not interfere. Every caring car owner is interested in how to repair through corrosion of a car without resorting to replacing body parts.

There are several ways to solve this problem, namely:

Welding - a local approach to the fight against through rust, which implies the presence of special welding equipment and experience with it;
Patch - or "solder" - soldering a suitable piece of metal with a soldering iron and tin solder;
Grid - building up the missing fragment of the part using a special grid. Works in conjunction with fiberglass and epoxy resin.
Fiberglass - a special fiberglass putty and special material is required to create a multi-layered rigid surface.
Putty - this method is effective only when using a substrate on the back of the part and long-staple automotive putty.
Riveting is an outdated method and requires a special tool (riveter) or a hammer and rivets.

A special aluminum patch mesh is used as the main material, or a similar non-professional mesh with a small section is selected. Nowadays, you can get by with an ordinary household plastic, metal or fabric mesh.

Several suitable pieces are being prepared. By stretching one of them from the inside of the part and shaping the missing part, the mesh is attached using masking tape. Epoxy resin is applied layer by layer on the mesh.

Each layer should dry well.So you need to repeat with the next piece of the grid. And so we close up until a hard surface is obtained.

From this material, you can make not only a fragment, but the whole part. The sequence of actions is the same as with the mesh (the rust hole on the car body is sealed), but using fiberglass. In fact, the frame of the missing element is being created.

It is possible to remove body corrosion only if a certain sequence of actions in this process is followed. Despite the variety of do-it-yourself corrosion repair methods, a motorist should know what to do with through corrosion of the body at the beginning of work. The complexity of the work itself will depend on the general condition of the car body.

To begin with, it is necessary to clean the surface subject to corrosion so that there is a clean piece of metal without traces of corrosion. If it is not possible to do this carefully, then the damaged fragment is cut out.

In each option for repairing through corrosion, all cleaned areas are covered with acid or epoxy primer.

From a suitable piece of metal (for body repair of through corrosion, metal with a thickness of 0.8 mm is needed), a patch is made 2-3 mm larger than the through hole. If possible, the patch is applied on the reverse side of the body part, and with the help of welding it is scalded with dots along the contour from the front side.

In no case should you weld with a continuous seam, so as not to lead and tighten the metal.

Welding points are cleaned flush with the repair area. It turns out a depression, which is then leveled with automotive putties.

The principle of operation is the same as for welding, but instead of metal 0.8, tin is used (for example, cut out from under a tin). The patch is cut out a little more than the repair place. With the help of a powerful soldering iron and tin solder, the patch is soldered with a continuous seam.

The protruding soldered area on the car can be slightly drowned with a hammer, but this will complicate further work with putty, so care and accuracy must be observed.

For such repairs, only special automotive fiberglass putty is used. Starting from a large (starting) and ending with a small (finishing) fraction. To do this, you will definitely need a substrate (for example, a piece of abrasive skin).

Work surfaces must be degreased and primed with acid or epoxy primer and allowed to dry. After priming, the putty will be applied in layers. For adhesion of materials, they put at risk with abrasive sandpaper (H 120-150). The surface is degreased again and putty is applied in a thin layer.

Each layer is thoroughly dried from 30 minutes to several hours, depending on the thickness and air temperature. The dried putty is rubbed with an abrasive, smoothing the boundaries of the resulting halo.

The result is a flat surface for applying primer and paint.

The thickness of the automotive putty layer should not exceed 2 mm. Thicker layers will cause the material to crack.

Whatever method of repairing through corrosion of the body is carried out, cosmetic painting work will definitely be needed to complete it. This includes layering the repair surface with several types of automotive fillers.

Each layer is dried and rubbed with abrasives. After that, the surface is primed with epoxy primer, then with leveling. After that, a paint coating is applied.

Painting a car or its parts requires special skills, so it is best to entrust it to professionals.

Through corrosion is a critical defect. Not only the appearance and reliability of the car, but also the safety of its owner depends on the condition of the body.Therefore, it is advisable to regularly inspect the body and perform preventive anti-corrosion treatment.

Of course, the most correct and radical solution to remove corrosion on a body part would be to replace the rusty part with a new one. But there are options that you simply cannot get such a part or its cost exceeds all reasonable limits, and the center of corrosion itself is not very large.
If this is the case for you, then read on.

There are many ways to deal with body corrosion, but the essence is about the same and they are all quite laborious. I will describe one of them to you, I will try in sufficient detail, if anything is not clear, write questions below in the comments.

We remove the corrosion of the body and then protect it in several stages.

The first stage is a rough cleaning of the corrosive place

With the help of a brush, preferably the most rigid one worn on a drill or a vinyl circle, a layer of paint, soil and rusty scale is removed.

Attention! Do not use an abrasive such as a grinder - it burns through the metal and then in this place it will rot very quickly.

Now, you can assess the problem area, how deep the corrosion is and whether there is through corrosion of the part. To do this, blow the cleaned place with air from the compressor and place a lantern or spotlight behind the parts. If this is a non-removable part, try to stick a light source in the back.
Here the main trick is to see the light in the form of points in places where there may be holes. Turn off outside lights if necessary. No through corrosion - excellent, there is - it will have to be eliminated.

The second stage - remove through corrosion

The easiest way is to solder the corrosion holes with tin solder. For this you will need:

a powerful soldering iron (there is one in the form of a hatchet or an iron),
tin-lead solder (usually POS-61),
flux (soldering acid - a rust converter, usually based on phosphoric acid, is also suitable in this capacity),
and possibly a building hair dryer for external heating of the repair site, if the power of the soldering iron is not enough.

Attention! Before working with a new soldering iron, its tip (working surface) should be tinned.

Before you start to solder a repair place with through corrosion, you should remove all remaining rust, since solder will not stick to rust. And here the most important thing is not to be lazy - if laziness, then we return to the beginning of the article, where I advised buying a new part.

To remove the remains of rye, you will need various simple sharp tools and an abrasive skin. Simple devices are a pointed needle file or a piece of metal fabric or a knife with a sharp tip.

Walking with a rough abrasive sandpaper, for example P60-80, along the rust center, you will remove the surface layer of rust. Now you should remove or, more precisely, pick out the rust from the metal into which it has already eaten. In order for these places to be clearly visible, you should apply a rust converter with a brush and wait a couple of minutes. The ingrained rust will turn black and become clearly visible on white metal.

This is where you will need all kinds of pointed objects to pick out rotten metal. Show your imagination!

This process is the most tedious and time-consuming. Wash these areas regularly with a brush containing a rust converter. In this way, you will wash away the rust that you have picked off, and you will see where more effort needs to be made.

So, the place is cleared, we start servicing the repair place.

Attention! If the diameter of the through holes exceeds 2-3 mm, then you most likely will not be able to fill them with solder. Therefore, this method is acceptable when through corrosion in the form of a fine mesh is repaired. Otherwise, a piece of metal should be welded.

We apply a flux to the surface, in our case it will be a rust converter based on phosphoric acid, and until it dries, apply a layer of tin solder over the entire surface with a heated soldering iron, where there may be holes from through corrosion.
For better adhesion of tin solder, we constantly grease the evaporating acid (flux). If the metal is thick enough or a large area of the repair area, and the power of one soldering iron is not enough to warm up, then we use a hair dryer or a second soldering iron to help.

Soldering is best done outdoors or in a ventilated area, as acid, which is very harmful to the respiratory tract, evaporates, and the smell is not pleasant.
This stage is quite painstaking and does not tolerate hack work.
When finished, check with a light if there are any through holes left.

The repair place is tinned and all centers of through corrosion are soldered. Surfaces treated with a rust converter should be cleaned of acid residues. This should be done according to the instructions on the label for your rust converter. Usually this is washing with water or an alcohol-gasoline mixture.

Stage three - we protect the repair site

In order to prolong the service life of a body part repaired in this way, it must be properly protected from harmful atmospheric influences.
To do this, acid primer is applied to the bare metal and the tinned place of the body part with a paint sprayer, and then acrylic primer.
Now you can putty.

Remember! Do not put putty on acid soil!

If in the process of sanding the putty small rubbing to the metal appears - it's okay, just before the last priming with acrylic, "blow" these places again with acidic soil.

Well, in conclusion of the whole process of removing corrosion from the car body, it is necessary to protect the reverse side of the repair site. This is a must! Otherwise, this whole process made by your hands will go down the drain.

There are many ways to protect metal from corrosion, the main thing is to ensure that there is no access to moisture. To do this, you can prime with acid and acrylic primer, apply sealant, mastic or fill with movil or similar material.

The method of protection, of course, depends on the ease of access to the repair site. Ideally, of course, it should be primed.
If you do not crawl to this place with a paint sprayer, then try to apply the primer with a brush. It should be borne in mind that the application of primers with a brush is lower in quality of protection than with an airbrush. Therefore, after such priming, it is desirable to apply another protective composition like Movil or its analogues.

A red attack named rust annoys many motorists. The worse the car body is protected from corrosion at the factory (galvanization), the more often the owners will have to make efforts to eliminate red spots. Moreover, it is undesirable to delay the liquidation, since over time the damage to the metal only increases. As a result, in six months you will have to spend much more time and money than today. So, what is needed to remove rust and mushrooms with your own hands and how to remove them without harming the body.

Rust is the oxidation of metal, which occurs under the influence of air, water and static electricity. Therefore, the main reason for its occurrence is damage to the paintwork of the car body. Microcracks and physical damage allow air and moisture to get to the iron. The rate of destructive impact will depend on the degree of protection of the body itself and the aggressiveness of the environment. This is especially true in the winter period, when a lot of chemicals appear on our roads.

The above factors directly affect the shape, color and depth of corrosion. The people call them differently: “saffron mushrooms”, “bugs” or simply “rusty spots”, but they have the same essence (only the degree of neglect is different). A single spot of rust is easier to deal with than many small red dots. The latter usually indicates the poor quality of the metal or an unsuccessful body repair. The total processing area will be larger. Moreover, these points more often spread in depth, and not in breadth. Paint blistering also signals the need to remove corrosion that has begun to develop under the paintwork.

Rust progresses well in places of increased exposure to foreign objects: sand, dirt, stones.The hood suffers from small stones from under the tires of other cars, wheel arches from their own “emissions” (by the way, wide non-standard tires or rims contribute to great damage). The thresholds of the car are also among the first to rot due to the close proximity to the “aggressive environment”, plus unsuccessful curb exits exacerbate the situation.

We got acquainted with the reasons and places, let's move on to the methods for correct elimination. There are two methods that differ in the way rust is removed:

Mechanical - cleaning, priming, puttying, painting.
Chemical - rust converters or metal galvanizing kits.

You can’t do without the first method if the rust has strongly eaten into the metal. Then it is necessary to completely eliminate traces of corrosion until pure iron (ideally shiny) remains. This may require additional tools and tools, which we will discuss below in a step-by-step instruction.
The second option is suitable for hard-to-reach places. These can be bends on the bottom of the car or the inside of the arches, which are difficult to process by mechanical means. Depending on the agent, rust after chemical treatment may turn into foam (it is necessary to wash off with water and dry the surface) or harden and become covered with a protective layer suitable for painting. Be sure to read the instructions and recommendations for the use of chemistry before buying.
Before starting work, try to assess the extent of damage to the body and evaluate if you can pickle the damage with chemicals alone. For a positive result, it is necessary that “live” iron remains after the initial cleaning. If there are through holes or the final thickness of the metal after processing is too small, then a more serious body repair will be needed, that is, initially all these areas will need to be repaired using welding or fiberglass putty.

The ideal option is phosphoric acid. Apply a thin layer on the camelina, wait 10-30 seconds, wipe dry with a cotton pad. Eats rust, forms a phosphate film, which is not afraid of water and is inert.

Maxim Leonov

I have already tried orthophosphorus - this is still an old-fashioned method, I processed what I cleared. (As far as I know, all these inhibitors and converters are the very same, only in multi-colored bottles). Indeed, almost cleaned surfaces, this rubbish eliminates rust residues. But untouched, so to speak, terry thickets of corrosion do not particularly react to it. So, they will hiss a little, darken, turn pale and remain in place.