Work only at temperatures above +12°C, not in the open sun and not in strong winds.
Rust removal
Paste the repair area around with corrugated paper (crepe), so as not to accidentally damage the adjacent varnish.
Remove all visible and hidden rust with a triangular scraper or screwdriver and sandpaper with a grit size of 120.
After that, grind the edges around the damaged area to a healthy varnish to a width of one to two centimeters with sandpaper with a grit size of 320.
On galvanized body parts, grind, if possible, not to a galvanized surface, but only to a primer.
Applying an anti-corrosion primer (Primer).
Remove dust, degrease and dry the repair site with a nitro-solvent and a clean cloth.
To avoid unforeseen problems, the Primer and the subsequently applied top coat should be from the same manufacturer. Otherwise, the varnish may bubble or wrinkle.
Primer is sprayed very thinly onto derusted sheet metal. but in a continuous layer from a distance of about 25 cm. To avoid settling of the aerosol on adjacent parts, they should be covered with adhesive tape and newsprint.
After 10-15 minutes of drying, you can apply the next layer. If the repair site needs to be puttied. Primer must be completely dry beforehand.
Putty
There are 2 types of putty: two-component and finishing. Two-component putty immediately before work is mixed with a hardener. It cures quickly and must be applied without delay. This putty is used to level large irregularities in tin. Fine putty is intended for the final smoothing of irregularities. It can be applied in several steps. Both types of putty are available in tubes and cans, while filling putty is also available in aerosol cans. Although the packaging often still recommends direct application of putty to bare sheet metal, it is advisable to pre-treat with Primer in each case.
Apply a two-component putty to the straightened or repaired area with fiberglass and allow it to cure. Pay attention to the manufacturer's instructions for use.
After drying, grind the irregularities by hand or using a grinder. To do this, use sandpaper with a grit size of 1 VO. You can also use waterproof sandpaper. In this case, the place of repair and sandpaper during the grinding process should be abundantly moistened with water from time to time (with a sponge).
In conclusion, wipe the repair site clean and dry.
Using a wide elastic plastic spatula, cover the area to be repaired with fine putty and dry for at least two hours. It is recommended to apply finishing putty to places of sharp roundings and bends from an aerosol can.
Depending on the thickness of the coating, the finishing putty dries well within two to three hours.
Grinding
Sandpaper varies in grain size. The smaller the number indicating the grain size, the rougher the ground surface. For sanding two-component putty, a grit size of 180 to 240 is recommended; for filler putty and old varnish, wet sanding with 360 grit paper is used. For final wet sanding, sanding with 600 grit sanding paper is recommended.
The finished puttied place is wet sanded with sandpaper with a grain size of 360, while the water above the grinding point is constantly squeezed out of the sponge. The sponge is immersed in clean water from time to time and soaked again.
For final wet sanding, a special waterproof sandpaper with a grit size of 600 is best suited, while during the sanding process both the adjoining sanding site and the applied varnish are sanded at the same time. Sanding is carried out only along the longitudinal axis of the vehicle: then the small grooves remaining after sanding under the varnish layer are barely visible.
Cleaning
Before spraying the varnish, the sanded surface, as well as the adjacent varnish at a distance of one to two palms, must be cleaned of grease and silicone residues. Silicone remover works best for this.
After grinding, thoroughly clean the area to be repaired and paste over all adjacent surfaces of the car accurately enough with newsprint and adhesive tape. When varnishing the wings, also carefully paste over the tires and bumper.
If possible, glue the area to be repaired so that the varnished surface ends at the nearest lining or body edge, since a flash of varnish forms at the edge of the pasting. If the closest smooth transition to the original lacquer is far away, the pasting should be carried out at a distance of two palms from the area being repaired.
Moisten the floor with water to bind dust.
Varnishing
To avoid problems, the Primer and the subsequent spray-on varnish must be from the same manufacturer. Otherwise, the pack may bubble or wrinkle. Attention: It is recommended to work out the varnishing process first on a piece of suitable sheet metal, for example, on an old wing.
Before varnishing, the part must be dried and dust-free. If possible, blow it off with compressed air.
Moisten the floor with water to bind dust.
Wipe the area to be repaired over the varnished surface with a silicone remover. An even more optimal base for the adhesion of the varnish is obtained by rubbing the cleaned surface on a silicone-containing polishing paste.
Shake the aerosol can vigorously for three minutes before use, otherwise the lacquer protrusions will form on the tin.
At the final application of varnish type "metallic" spray some of it on paper to remove any metal particles that may have been trapped in the lift tube of the can.
Large surfaces, whether vertical or horizontal, are sprayed crosswise: starting from the adjacent outer surface and deflecting the jet outward in the other direction.
Small surfaces are sprayed in a spiral pattern from outside to inside to reduce the surface of the jet.
Move the can at a constant speed and at the same distance relative to the surface. The recommended distance is approximately 25 cm.
In order to obtain as imperceptible a transition to the previous lacquer as possible, it is best to apply the lacquer in at least 4 coats. Each new layer should be 2-3 centimeters wider than the previous one.
Attention: If the varnish is sprayed from a very close distance or with too slow or variable jet speed, so-called varnish protrusions occur. This means that the varnish flows down in some places due to the fact that there was a lot of it in these places. The same occurs when the jet direction change does not take place on a surface covered with paper.
Repeat the varnish spraying process with 5-minute pauses for pouring the solvent until a coating of sufficient thickness is formed. It is especially necessary to shake in pauses a can of varnish of the type "metallic", since the metal particles settle quickly.
Attention: Make sure that the color of the used varnish matches the type "metallic" with the original varnish is very difficult. Pigmentation (aluminum particle distribution) becomes more uniform if the last layer is applied from a distance of 30 cm instead of 25 cm. Some equalization of the color tone allows this technique to be achieved: a slow movement of the hand, and thus a rich coating, makes the color tone darker, and a fast movement of the jet makes it, on the contrary, lighter.
Applied base coat type "metallic" it is necessary to cover with a transparent varnish, only after that the varnish of the type "metallic" takes on its lustre. Spraying is performed again in 3-4 thin layers, and each time a pause of several minutes must be maintained between the processes of applying varnish. Before applying the first coat, the base coat must dry for at least 30 minutes. The surface to be varnished with clear varnish should be wider than the surface covered with base varnish by about the width of the palm of your hand. To do this, the paper cover should be moved apart accordingly.
Clean the can nozzle. To do this, turn the can upside down and spray the varnish until it stops flowing.
Immediately after the completion of paintwork, remove all paper coatings. Due to this, if the coating has been sprayed, the liquid varnish can run off at the transition zone.
Dry the applied varnish. The drying process can be accelerated by using a heater or a strong photo lamp.
Attention: Do not use a heater with a fan, as the particles raised by the air stream will stick to the fresh coating.
After the paint has dried, i.e. not earlier than 48 hours, carefully remove the paint coating on the surfaces adjacent to the repaired area using a mild polishing agent and a cotton swab. In this case, polish only along the longitudinal axis of the vehicle.