Do-it-yourself spot painting of a car: paint selection, work order

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Spot painting of cars is a difficult category of work in the painting business. Therefore, it is especially important that at the initial stage the novice car painter has a clear and understandable step-by-step instruction. This article gives the secrets of the skill of master instructors in training painters.

Full, local and spot painting

First you need to understand the terminology. It is important to understand that "spot painting of a car body" is a term for the most part commercial. It is needed by car service managers and workshop owners to advertise their services.

Painters in this case say "stain painting" and "lacquer breakage", which accurately reflect the essence of the process, but may be incomprehensible to the client.

Local - this means local, not going beyond certain limits. On the body of the vehicle, we may, at our discretion, set these boundaries, including one or more parts.

It turns out that the term "local painting" can reasonably be used when the repair area is limited to one or more partsbody. For example, on a brand new car, two parts were damaged at once: the rear door and the rear fender. In this case, the repair area will be limited to them, since there is no point in painting the entire car for this reason alone. Another thing is when the same damage happens on an expensive, but already old foreign car with minor damage throughout the body. Then it will be quite logical and economically justified to make a "full painting" of the body.

In what cases is spot painting of a car used

There are only three factors that go into making a decision on this issue:

1. Amount of damage to be repaired.

2. Where is the damage located.

3. What type of paint is your car.

Let's consider all the options and take the front door of a car as an example. If the body color is light metallic, black or dark of any shade, the defect is located approximately in the center of the door, and its size is more than five centimeters in length, then the chances of success are close to zero, and a complete painting of the car door is inevitable.

If a defect of the same size is located in any lower corner of the door near the edge, then success is almost guaranteed.

Now just change the color of the door to white, and the location of the defect will no longer matter.

Conclusion. Do-it-yourself spot painting of a car is quite feasible if you need to repair minor damage to the bumpers or the lower part of the car body.

How to choose paint

Today, the purchase of car repair paint stoppedbe a problem. Even in rural areas, almost every regional center has laboratories for the selection of car enamels. There you can order paint in an amount of 100 grams for any car. But before you go there, you need to familiarize yourself with some details, the understanding of which will save time and nerves.

What every car owner needs to know about selecting paint for spot painting a car?

1. Most modern cars are painted in factories using a "two-layer" system: paint + varnish.

2. On average, 150 grams of paint is spent on one part of the machine during repair painting. And the same amount of clear lacquer. For example, to paint a car door only from the outside, it is enough to order 150 grams of paint and varnish. 100 grams are enough for the front fender, and 200 -300 grams for the bumper, depending on the size.

If you plan to touch up defects on your car yourself, order 100 grams of paint. It will be sold to you in a plastic container with a volume of 200 milliliters. Pour the rest of the paint into a small clean plastic bottle and screw the cap on tightly. In this form, it will never dry.

3. The computer does not select, but simply issues a recipe according to the color code of your machine. Therefore, it is important that the colorist (color specialist) who will make your paint, not just assemble it according to a computer recipe, but manually modify it and fit it to your machine. Because the better the paint is matched, the smaller the stain of your spot repair will be.

According to the results of his work, the colorist mustalong with the paint, give you a test color, by which you can check the quality of the selection. Of course, you will have to pay about 500 rubles for such a service, but you should not save on this.

Materials and equipment for spot painting

Here is the minimum list of materials and tools that you cannot do without. All consumables can be purchased in Russia, at a low price.

1. Degreaser - 1 bottle.

2. Acrylic thinner - 1 bottle.

3. Sandpaper waterproof with grit R 240, R 320, R 600, R 800, R 2000 - 1 sheet each.

4. Scotch-brite gray (abrasive tape in rolls) - 10 cm.

5. Primer car acrylic gray in an aerosol can - 1 piece

6. Masking tape (paper masking tape) - 1 roll.

7. The napkin is sticky. Designed to remove dust from the painting area.

8. The polish is coarse. Ideally - 3M firms - 50 grams.

9. Suede synthetic. Designed to collect moisture.

10. Orange polishing wheel. Medium hardness.

11. Spray gun type HVLP mini.

12. Small compressor. You can buy, make your own or rent.

Safety

When performing any painting work, the most unexpected surprise for you may be getting solvent in your eye! Believe me, it won't seem like a little! Most often this happens when cleaning the spray gun after finishing work. Wear safety goggles and gloves! As a last resort, keep clean water nearby to rinse the eye immediately.

Spot painting of the car. Work order

Before starting all work, remove all contamination from the surface of the machine in the repair area. It is important not only to wash off dust and dirt, but also to remove particles of bitumen, traces of insects, and tree resin. The repair area is the entire body element on which the spot defect will be painted over. For example, if you paint over a scratch on a wing, you clean the entire wing. Bitumen is removed with a degreaser. Everything else - with acrylic thinner, in no case 646, 650. They are very aggressive. We do so. We take a piece of clean cotton fabric the size of a handkerchief, literally moisten the corner of the fabric with three drops of solvent and erase the glue of trees or traces of insects, then wipe it with a dry end. And so we delete each point.

Now proceed directly to the repair. For clarity, let's say that you hit the curb with your front bumper and scratched the bumper at the bottom right. Machine color - silver metallic.

Take a quarter of a sheet of P 240 sanding paper and completely cut off the scratch, just try not to go beyond its borders so as not to expand the repair area, otherwise you will have to paint the entire bumper, repairwill turn from spot to local painting, and 100 grams of paint will definitely not be enough for you.

The next step is a step-by-step regrinding of the coarse marks from the first abrasive. First with sanding paper P 320, then with P 600.

After that, we take a gray scotch brite, with light circular motions we knock down the gloss (matte the varnish) around the polished spot, expanding the repair area by 5-10 centimeters in a circle.

Thus, we have come to the priming stage, but first cover the parts of the machine adjacent to the defect site with masking tape and newspapers so that the soil does not get on them. Then clean the surface with a degreaser using regular paper towels.

Let the degreaser dry completely and apply one gloss coat of primer from a can so that its borders slightly extend onto the intact varnish around the place where you sanded the marks left after the grit P 320.

After the first coat of primer becomes completely matte, apply the second one exactly the same. Now you can rest a little. Until the soil is completely dry. Drying time is indicated on the bottle.

When the primer is dry, remove the newspapers that covered the machine, carefully sand the primer with P 800 abrasive, sawing off all the debris and smoothing out small irregularities. Then, with P 2000 abrasive, remove all small drops of soil, up to the borders of pasting with newspapers. Using scotch-brite tape, expand the repair spot by another 5 cm in a circle. Again, cover the adjacent area with newspapers, retreating further from the edge of haze by 15-20 centimeters, and degreasesurface.

You can start painting. Set the gun to the lowest possible flow rate and pressure, remove dust from the repair area with a sticky cloth and apply one medium coat of paint to the primer spot so that the layer is not very dry, but not very wet. Apply it layer by layer at intervals of 15 minutes until the edge of the primer is visible when viewed from the side. You need to look from the side, and not directly at the spot.

One more important note. Paint, unlike varnish, dries quickly and becomes matte. After 30 minutes, it hardens so much that it can be wiped with a sticky cloth to remove dust, if necessary, sanded with abrasives from P 1000 to P 2000, followed by continued painting. The product acquires its final shiny appearance only after applying varnish.

Try to apply the paint in such a way that it does not reach the limits of haze, because the transparent varnish, overlapping the paint, will be applied just to these limits.

After making sure that the primer is completely painted over, let the paint dry completely. This will take approximately 30 minutes. Then, with a sticky cloth, carefully remove dust from the entire surface of the repair area and apply clear varnish to the entire matte spot. It should not go into the gloss zone. Only small drops are allowed, which are then easily removed with P 2000 abrasive. If dried naturally in summer, the varnish can be polished after 24 hours.

Lacquer polishing

Polishing is an integral part of the technology of spot painting cars. To make the border of the repair spot invisible, you need tosandpaper P 2000 cut off dry grains of varnish. And then, using a polishing paste and a foam rubber wheel, polish the risks from the previous abrasive. Dust stuck in the varnish is removed in the same way.

The polishing process can be mechanized by inserting a Velcro disc (available at paint shops) into the drill and attaching a polishing wheel to it.

Car wash after painting

You can safely wash the repair site with water and a sponge a day after applying the varnish. If you need to wash your car at a car wash, show the washer the painting area and ask him to reduce the pressure in the washer to a minimum when he washes off the foam there. After 1.5 months, you can not reduce the pressure.

Conclusion

The main advantages of spot painting a car are environmental friendliness and economy. This combination allows many car owners, especially in rural areas, to repair scratches, chips, small dents on the car on their own.