Local body repair is an art available to anyone who is willing to spend time studying the nuances. Painting a car with a stain with the transition with your own hands allows you to save significant funds, avoiding complete repainting of the part. This method is ideal for eliminating chips, scratches and scuffs, when there is no need to affect the entire plane of the element.
The main difficulty is to create an imperceptible transition between new coating and old paint. Proper surface preparation and competent mixing of materials is the key to success. If you want to get a result that is indistinguishable from the factory, you will have to strictly follow the technology at each stage.
In this article, we will analyze all the subtleties of the process, from the selection of enamel to the finish polishing. You will learn what tools are needed and how to avoid the typical beginner mistakes. A careful study of the material will help you to perform the work qualitatively the first time.
Workplace preparation and selection of materials
The quality of painting depends on the conditions in which it is carried out. Dust, drafts and poor lighting can negate all efforts. Organization of space - the first step to success. You will need a clean, well-ventilated room where the temperature does not fall below +18 degrees Celsius.
The work will require a specific set of tools and consumables. The use of inappropriate materials can lead to detachment of the paint or the appearance of defects. Pay special attention to the choice solvent and hardener, they must correspond to the type of paint coating.
⚠️ Warning: Never paint in a dusty garage without first wet cleaning the floor and walls. Dust, settled on fresh varnish, will spoil the appearance and require time-consuming grinding.
The necessary arsenal includes grinding circles of different grains, degreasing, paint scotch and spray gun with a duse of 1.3-1.4 mm. It is critically important to have respiratory And protective glasses, because solvent vapors are toxic.
- 🛡️ Respirator with a carbon filter to protect the respiratory system.
- 🔧 Krascopult with the adjustment of the torch and the supply of material.
- 🧴 Degreasing and antisilicone for surface preparation.
- 📏 Grinder or bars with sandpaper P80-P2000.
Before starting work, check the serviceability of the compressor and moisture separator. Getting oil or water in the paint is a fatal mistake. Air filtration It has to be perfect.
Technology of color selection and transition
The most difficult step is to get into the color. Even if you buy the paint code, the shade may differ due to the burnout of the old coating. Computer-assisted selection Colorist color significantly increases the chances of success. However, additional tone adjustment is often required immediately before application.
Creating a transition (stewing) requires an understanding of the work of pigments. Metals and pearls change hue depending on the angle of incidence of light and the size of flakes (particles). To hide the border, a technique is used. stretching Color on the adjacent body elements.
To create a smooth gradient, the master uses a special solvent-transmitter (blend solvent). It blurs the boundary between the new and the old layer, making it invisible. It is important to correctly calculate the proportions of mixing the base with the solvent.
⚠️ Note: When working with metallic be sure to make test sprays on cardboard or old parts. The color in the car and in the bank can be very different.
The process of selection can take longer than the painting itself. Don’t rush to mix large volumes, start with small samples. Visual assessment In different lighting (day and artificial) is mandatory.
If the color is chosen incorrectly, the transition will be noticeable, creating the effect of a “pad”. In this case, you will have to wash the layer and start again. Patience at this stage is a key factor.
Why can't the color match?
Even the same paint of different parties may differ. In addition, the old coating burns out under ultraviolet light, changing the saturation. The new layer will always be brighter if you do not use the transition technique or polish the old varnish to equalize the shine.
Preparation of the surface for local painting**
High-quality adhesion (clutch) of materials is possible only on a perfectly prepared surface. Start with cleaning and drying the repair area. Then, the damaged area is cleaned to the metal or soil, if the depth of the defect is high.
The method of “nailing” or grinding the boundaries of the old lacquer is used. The area around the damage is treated with a P800-P1000 abrasive, creating a matte patch with a diameter of 15-20 cm. This is to ensure that the new material does not detach over time.
After machining, the surface is thoroughly degreased. You need to wipe with two napkins: the first wet, the second dry. It is important not to touch the prepared area with your hands, as fat fingerprints will lead to defects.
- 🧼 Careful washing of the repair area with auto shampoo.
- 🪒 Sweeping chips and scratches to the ground.
- 🌫️ Floating the surrounding varnish with abrasive P1000.
- 🧽 Anti-silicone degreasing in two aisles.
Sticking adjacent elements with paint tape and paper is the final step of preparation. The edges of the paper should be turned to avoid the step on the boundary of color. Tightness The shelter will protect the rest of the body from pollination.
☑️ Checklist of preparations
The process of applying the base enamel
Deploying the base is the moment of truth. The Krascopult is held perpendicular to the surface at a distance of 15-20 cm. Movements should be smooth and uniform. The first layer is applied thin, "dust" to set adhesion.
The second and third layers are applied with a full cover (usually 50%). It is important to monitor the spray torch here. To create a transition, the last layer of the base is stretched by a solvent outside the repair zone. This creates a pigment concentration gradient.
Between the layers, a pause must be maintained for the evaporation of the solvent (interlayer drying). It is usually 10-15 minutes at a temperature of +20 ° C. If you do not let the solvent escape, bubbles or “boiling” may appear on the surface.
Pay special attention to the edges of the paint spot. The movements of the gun must end outside the detail to avoid inundations. Uniformity The layer is the main criterion of quality.
⚠️ Please note: Do not try to paint everything with a thick layer the first time. This will lead to leakage and long drying. Better 3 thin layers than one fat.
After applying the last layer of the base, let it stand for 20-30 minutes. It should become matte (for acrylics) or simply dry (for a base under varnish). Only then can we begin to varnish.
The key mistake of beginners is insufficient drying between the layers of the base, which leads to the dissolution of the lower layer and the appearance of matte spots after varnishing.
Applying lacquer with creating a smooth transition
The polish protects the base and gives depth to the color. The technology of varnishing with transition requires special care. Lacquer is applied in 2-3 layers. The first layer is thin, binding.
The second layer is applied more abundantly, creating a gloss and "body" of the coating. It is at this stage that the transition is formed. The varnishing boundary should be wider than the base boundary. A special application is used to soften the edge. transition-solvent.
It is applied to the junction of new and old lacquer, blurring the border. The movements must be fast and light so as not to dissolve the bottom layer into holes. This process requires skill, so practice on unnecessary detail.
| Parameter | First layer | Second layer | Transition layer |
|---|---|---|---|
| Thickness | Thin (dust) | Wet, glossy | Thin, solvent-free. |
| Distance | 20-25 cm | 15-20 cm | 20-25 cm |
| Time to dry | 10-15 minutes | 20-30 minutes | Don't dry, polish right away. |
| Purpose | adhesion | Depth and protection | Hiding the border |
After the varnish has dried (complete polymerization takes 24 hours to a week depending on the hardener), the surface is ready to be polished. Immediately after drying, the transition can be noticeable, but it is removed with abrasives.
It is important not to overdo it with the solvent transition, otherwise the varnish can become cloudy or go "craters". Balance The difference between dissolving the border and preserving the structure of the lacquer is critical.
Use a special solvent for transitions (Blend Solvent). A common solvent 647 or 470 may be too aggressive and may damage the varnish structure at the junction boundary.
Finishing polishing and elimination of defects
The polishing is the final touch that hides the traces of the repair. Even experienced craftsmen do not avoid light pearls (orange peel) or dust. Abrasive polishing removes these irregularities.
The process begins with the grinding of the transition zone with water or dry abrasive P2000-P3000. The goal is to make the surface matte and flat, removing the varnish step. Be careful not to wipe the varnish to the base.
Then a polishing machine with circles of different rigidity is used. First, a coarse paste is used to remove drawings, then finely abrasive for the gloss effect. Finishing polish It brings back the mirror shine.
- 🌊 Resurfacing the transition zone with the abrasive P3000.
- 🌀 Polishing in a hard circle with abrasive paste.
- ✨ Finish polishing with a soft glossy circle.
- 🧼 Clean the surface and apply protective wax.
The result should be a homogeneous surface, where it is impossible to determine the place of repair by eye. If the transition is still visible, the grinding and polishing procedure is repeated, but with greater caution.
Remember that after polishing, it is advisable to let the coating stand for a couple of weeks before the first wash with chemistry. This will allow the varnish to gain final hardness.
Do I need to remove the part to paint the stain?
Not necessarily, but desirable. Removal of the part allows you to approach it from all sides, avoid getting paint on rubber seals and ensure uniform drying. However, experienced craftsmen often paint on site, carefully covering adjacent elements.
How much dried varnish before polishing?
Depends on the type of hardener. For fast - 1-2 hours, for standard - 12-24 hours, for slow - up to 48 hours. You can not polish too early: the varnish will clog the abrasive. It is also more difficult to polish too late (after a month) as the polish becomes very hard.
Can I paint a black matte color with a stain?
Painting matte flowers with a spot is one of the most difficult tasks. The mat is not polished, so the transition is almost impossible without a visible border. Usually, matte elements are painted completely or use special airbrushing techniques, but not the classic transition with a solvent.
What to do if the stripes appear after painting?
If the stripes appeared immediately, it may have mismixed the paint or misconfigured the torch. If after the varnish, there could be a reaction of layers. In most cases, the stripes are removed by polishing, if they are not deep. In the worst case, you will have to repaint.