Almost all types of paints must be diluted before use by mixing with one or another solvent, which facilitates the application process and increases the level of protection of the coating from rust. Dilution proportions depend on many factors.
Almost all paints need to be thinned with a solvent, but the choice of solvent depends on the paint and many other factors First of all, it is necessary to determine the degree of paint fullness. This indicator indicates the concentration of the dye (the amount of solvent already present). The higher the degree of fullness, the more you can dilute. It should be noted that the process of painting with highly filled paint is much simpler, material consumption is reduced, it adheres better, especially when it comes to painting metal and protecting it from rust. This indicator is ranked with the following notation(from least diluted to most full):
Types of coloring materials
This is the main factor that determines which paint thinner you can use.
Acrylic enamel
Consists of several components. Before painting, mix with hardener and dilute with thinner to the desired consistency. Suitable solvents for diluting it:
- R-12;
- 650 (soft enough, so suitable for many coloring agents);
A universal material, it is used not only for painting surfaces made of various materials, but also used as an anti-rust primer.
- toluene;
- xylene;
- white spirit (it is better to use artistic white spirit, since regular white spirit may contain impurities that precipitate).
Alkyd enamel can still be used to prime anything against rust. It should be noted that there are types of alkyd enamels that do not require dilution, for example, PF-15 and “Extra”. As an alternative to alkyd, oil-phthalic enamel can be used. Its properties are similar to PF-115, but it does not have strong smell. This type has excellent consumption, bright colors and resistance to chemical and weather influences.
Nitro enamels
Any type of solvent is suitable for this paint option, but it is better to use the one recommended by the manufacturer. When diluting nitro enamels, you can use 646 (it is also suitable for primer), however, please note that this is a very aggressive type of diluent and must be used carefully.
Water-based paint
Alcohol or ether. It is important to remember that the water must be distilled, since ordinary water, even fresh water, contains a large amount of salt impurities, which, when the coating dries, can cause white coating. Alcohol may not be compatible with the colorant, so check for small quantity Before diluting the entire volume, if the paint being tested does not curdle after dilution with alcohol, then the substances are compatible and this thinner can be used.
If, when you add alcohol to the paint, it curls, then this paint is not suitable for thinning with alcohol. Filler
The filler is soil, preparatory material It is no less important to dilute correctly than the coating that is supposed to be applied after it. The main task of the primer is to smooth out micro-irregularities of the surface before painting, which is not only necessary when painting, but also protects against rust in the future.
If the primer film is too thin, it will not be able to cover all defects and depressions and will have to be reapplied, which leads to additional costs. If the soil is too thick, its penetrating and rust-protecting ability will be reduced and it will again not be able to fill uneven surfaces. The material will begin to peel off and will not be able to spread, resulting in a layer that will have to be removed by sanding.
Solvents that can be used for primer:
- solvent;
- xylene;
- a mixture of solvent or xylene with white spirit.
It should be noted that 20% diluent is added to one-component primers, and two-component primers are diluted in the proportions specified by the manufacturer (2 kg to 1 kg, 3 kg to 1 kg, etc.).
When diluting paints and varnishes, you need to add thinner in small portions so as not to make a mistake with the proportions. This will reduce the consumption of both the product itself and the base material.
An insufficient amount of thinning material increases paint consumption (kg per m2) and makes the coating uneven. Excess leads to smudges and stains; you have to reapply enamel, which also increases its consumption.
To further resist rust and protect the surface being painted, powdered metals can be added to the solution.
The proportion of metal powder added to paint solvent per 1 kg is determined individually, depending on the manufacturer’s recommendations.
When working with solvents, you must remember to take precautions: use gloves and a mask, ventilate the room. If the solvent gets on your skin or eyes, you should promptly rinse these areas. warm water with soap and consult a doctor.
Cocktails are different, and not all of them are intended to be taken “on the chest”. Paints and varnishes that we use for restoration paint coating car - these are, in fact, also cocktails - properly prepared mixtures of several ingredients. And since we strive to ensure that the restored car (fender, door) after repair sparkles brighter than a new one, and the paint lies evenly, then our “paint cocktail” must be prepared competently, carefully and carefully, and not concocted anyhow.
Today you will find out
Ingredients
First of all, let’s decide on the type of our “paint cocktail”: will it be regular acrylic enamel (which is less likely), or metallic or pearlescent paint (most likely).
Regular acrylic enamel is two-component, with a hardener. The “ingredient kit” for such materials consists of three jars. For example, a liter of paint, half a liter of hardener and 100-150 ml of thinner. That is, when buying a liter of paint, you actually get about 1.6-1.7 liters of diluted paint.
In the case of “metallic”, the base paint is necessarily covered with a transparent varnish on top - without it, spectacular coatings look inconspicuous, and the weather resistance of two-layer coatings is much higher. Transparent varnish, like acrylic enamel, is two-component, with a hardener. But the “base” does not need a hardener - it is one-component.
Thus, the “set” for two-layer coatings already consists of five cans. For example, a liter of “base”, 500-700 ml of thinner for it, a liter of transparent topcoat varnish, half a liter of hardener and 100-150 ml of varnish thinner - a total of 3.3 liters! At the same time, the diluted paint itself was no longer there, the same 1.7 liters.
Making a batch
Before filling the gun, you should mix the components of the purchased paint.
For proper mixing of the components, which produces a painting material of the required viscosity, the following conditions must be met.
Dishes
It is important that the container in which we mix is strictly cylindrical in shape ( flat bottom and vertical walls). Only in such a container can you mix the components evenly and measure their quantities correctly.
It is better if it is a special measuring container in the form of a transparent plastic jar with a lid. Such cans are marked with markings that allow mixing materials in the required volume ratio (1:1, 2:1, 3:1, 4:1, 5:1, etc.).
Measuring containers are available in different volumes, ranging from 100 ml to almost half a bucket
Also, for dispensing and mixing paints and varnishes, it is convenient to use a special ruler with marks that determine the volume fractions of the components.
Pour the base into a cylindrical container to a certain division, and then add the hardener (if added) to the required mark, then the solvent. Mix everything with the same ruler - and you're done. Often measuring ruler is sold together with a paint kit, and all branded cans indicate the proportions according to these lines.
It is convenient to measure the required amount of components using a measuring ruler. Then I chatted with the same ruler - and that’s it.
Proportions
Given the abundance that has reigned on the paint and varnish market, it is, as they say, impossible to give one recipe for all occasions by definition. Yes, and you don’t need to do this. There is TDS - you know who the rest is from.
However, it would be useful to provide some general guidelines. In principle, we already talked about them a little higher: up to 50% hardener and 10-20% thinner are usually added to two-component products. The degree of dilution of base enamels usually ranges from 50-80%. Well, look at the exact proportions in the instructions for a specific product: all can varnishes and enamels have instructions in the form of pictograms that inform you in what proportion you need to dilute the paint with the hardener (if the material is two-component) and thinner.
We remind you: only thinner is added to one-component materials (alkyds, base enamels, 1K primers); into two-component materials ( acrylic enamels and varnishes, 2K primers), first a hardener is added, then the mixture is brought to the desired viscosity with a thinner.
If you order paint for selection in a laboratory, then you will be given a set of components (usually ordered as a set), by mixing which you will get a ready-to-use material with a working viscosity - as they say, “for a spray.” Or they will give you paint that has already been diluted (of course, this only applies to the base, since the lifetime of two-component materials after mixing is strictly limited).
Supplements
A description of recipes for preparing paint cocktails would be incomplete without mentioning additives - materials used to change the individual characteristics of enamels, varnishes or primers.
For example, to create a rough surface - very often they are painted this way. plastic bumpers SUVs - there are structural additives of varying degrees of granularity. In general, to prevent paint on plastic from cracking, 20-40% plasticizer must be added to it. There are matting elasticizers designed to reduce shine and coloration. plastic parts type of side trims of Mercedes-Benz cars.
When painting with spectacular two-layer coatings, these additives must be mixed with the topcoat varnish (it is recommended to add a plasticizer to the filler primer as well). Read more about additives and their use.
Measuring viscosity
Any painter should be able to control such a vital indicator as viscosity. For what? So that it corresponds to the recommended value. Again, why? To evenly apply the material to the surface and obtain a coating of the required thickness with the planned properties - beautiful and durable.
“Viscosity” (from Latin viscosus - sticky, sticky) is a value characterizing the fluidity of a liquid.
For what?
Filtering
The prepared paint and varnish material must be filtered before filling into the spray gun tank, since it may contain foreign inclusions that got there during the preparation process, clots, etc. Otherwise, it is impossible to guarantee a high-quality surface, because all this debris may ultimately end up on the surface being painted.
For filtration, it is convenient to use disposable paper funnels with a nylon filter insert (mesh size, usually 190 microns). I inserted the funnel directly into the tank, strained it - ready, you can paint!
We fill the paint tank only using a filter funnel.
Basic mistakes
Achieve consistently High Quality The work performed is possible only if technological recommendations for the use of certain materials are observed. There is simply no other way for those who want to repair modern cars and repair them efficiently.
Meanwhile, ignoring technological requirements remains the main (!) cause of defects and errors. As they say, “...how many times have they told the world”...
But “free morals” have always been and will be: we adjust the spray gun “by ear”, we mix the paint “by eye”, we forget about the strictly defined “lifetimes” of products prepared for use.
For example, in an hour the varnish changes its viscosity by an average of 100%. It's thickening. Before lunch we stirred it, measured the viscosity - 20, went away to eat satisfied, returned 50 minutes later, and it was already at 40! Of course, the material can no longer be used. But how often does anyone consider such “trifles”?
How often does anyone remember that a material into which we have not added enough hardener will no longer be able to properly harden, no matter how dry it is. Acrylic two-component materials are cured in the same way: due to chemical reaction between an acrylic binder (base) and a substance for cross-linking molecules - polyisocyanate (hardener). And only the paint manufacturer can know what number of -N=C=O units (present in the hardener) is necessary to react with a certain number of OH units (found in the base) and transform the material into a durable polymer film (more on this).
So it turns out that if we do not pour enough hardener, there simply is not enough crosslinking material to properly cure the film. The coating is soft and uncured.
The opposite situation - with an excess of hardener (and, accordingly, an excess of -N=C=O units) has the opposite effect - the coating turns out to be too hard, but at the same time inelastic, highly susceptible to peeling, cracking, and chipping.
So if the can of varnish says to dilute it in a ratio of 2:1, then you need to take the time to measure exactly two parts of varnish and one part of hardener. No more, no less.
Correct polymerization of two-component materials is possible only if the correct mixing proportions with the hardener are observed
Well, the fact that acrylic materials can be cured only with original hardeners is not subject to discussion at all. In acrylic systems, the copolymer and polyisocyanate are carefully selected for each other, and if we take a hardener from another varnish or another manufacturer, we will get a different polymer with completely different properties.
The jar with the remaining hardener must be tightly closed, since the hardener reacts with air moisture, resulting in its cloudiness and loss of crystals, sometimes gelling. To prevent air from entering the partially used can of hardener, it is recommended to turn it over and place it on the lid, and store it in this position.
Taking a general look at the problem of preparing paint for application to a surface, it seems that there is nothing complicated about it. If you carefully study the instructions with the manufacturer's recommendations regarding the solvent concentration, the degree of paint viscosity and other instructions, it is almost impossible to make a mistake. But you should also take into account that the instructions for using a particular product also include a commercial component, that is, advice to use products of the same brand, and this can significantly increase your costs.
If you know the principle by which enamels and solvents interact and what the technology is for preparing paint for application on a car, you can save money by replacing expensive solvents famous brands no less high-quality domestic license plates.
Basics of paint and solvent interaction
Various solvents. Click on photo to enlarge.
The result of painting largely depends on how to dilute the paint before applying it to the surface. Enamels for painting cars are initially a liquid mixture, but the addition of a solvent is necessary so that, firstly, it adheres better, and secondly, it forms a coating that will reliably protect the metal of the body from corrosion and mechanical damage. After painting, as the pigment dries, the solvent evaporates at a certain rate. According to this parameter, such compositions are classified into:
- fast, which are used if the paint is applied in low temperature conditions;
- slow (long), which are suitable for painting cars in the hot season;
- universal, intended for use during the transition season.
The final composition of the enamel mixture for painting a car is determined not only by the amount of solvent added to it immediately before application, but also by the concentration of components initially provided by the manufacturer. It is important that some substances in the paint remain active during storage. On this basis, enamels are divided into low-, medium- and high-filled with the corresponding abbreviations: LS (Low Solid) - low-filled, by the way, it is not recommended to dilute them too much; HD and HS, MS, UHS, VHS (Very High Solid) – highly filled.
What role does fullness play? First, high-fill paint is easier to apply. Secondly, volatility directly depends on the fullness, although the viscosity of all types of paints is approximately the same.
The features of the technology for preparing the enamel mixture are also determined by what solvent was used in the production of the paint, since both substances must have approximately the same chemical composition. It is also important what components underlie the enamel itself. For example, in order to separate acrylic lacquer and acrylic enamel, you can use the same solvent, since both varnish and enamel are the same acrylic, only with or without the addition of pigment.
Numbered solvents and their component composition
Each solvent contains such components as nefras, white spirit, toluene, solvent, butyl acetate, xylene, etc. The properties of the solvent are largely determined by the ratio in which it contains these substances.
Solvent No. 646 is very popular in the field painting works, since its composition is very aggressive. At the same time, due to its aggressiveness, this solvent can not only dilute the paint, but also change its composition, and therefore its properties. This solvent can be used to dilute the primer or paints and varnishes acrylic based, but you should be extremely careful.
Due to the fact that the quality of the substances included in solvent No. 646 is not always maintained at the proper level, professional painters It is recommended to use it only for cleaning guns after painting a car. Here the high aggressiveness of the solvent will come in handy.
White spirit is widely used in degreasing surfaces for painting. They cannot dilute acrylic-based paint, but they will work great to dissolve regular, slate or rubber-bitumen mastic. Regular white spirit may contain impurities that may precipitate over time, so more quality option considered artistic white spirit.
Solvent No. 647 is used when painting a car with nitro varnish or nitro enamel, but you should also be careful when working with it due to its aggressive composition.
Solvent No. 650 is softer. It is suitable for most paint materials.
Another popular composition is R-4. They're being scammed alkyd enamels and paints made on the basis of chlorinated polymers. For the latter, pure toluene or xylene is also suitable.
Polar and non-polar solvents
Example of paint solvents. Click on photo to enlarge.
The answer to the question of how to properly dilute paint is determined by what material is used to paint the car: polar or non-polar. The solvent should be selected based on the same criteria: if the car paint is made on the basis of a polar substance, then the means for dissolving it must also be polar. To be sure, it is better to purchase enamel and solvent from the same series.
Polar solvents include alcohols, ketones and other substances containing a hydroxyl group in their molecules. Non-polar products include kerosene, white spirit and several other compounds based on liquid hydrocarbons. So, water-based paint and water-soluble acrylic enamels interact well with alcohols and ethers, but they reject white spirit. Alcohol and white spirit are two completely different substances that under no circumstances can be replaced with each other.
Acetone reacts only with polar substances. Xylene can be considered a universal solvent, since it actively interacts with both polar and non-polar substances. Suitable for most classic enamels and benzene.
How to dilute paint correctly?
The process of painting a car body is quite complex. technological process with strict requirements for the quality of materials used. And before starting painting work, it is necessary to dilute the coloring composition to the required consistency and viscosity - without this it is very, very difficult to obtain a high-quality result. Let's get a look, how and with what to dilute paint for painting a car.
When preparatory work on the body are finished, there are still microcracks on the surface that are not visible to the eye. It is necessary to dilute the paint so that it can fill all cracks and microcavities. The dilution process allows you to reduce the viscosity of the composition and density. Due to dilution, the dye better adheres to the surface in a thin and uniform layer.
Also from physical properties The specificity of the work also depends on the particular coloring composition. If a spray gun will be used as the main working tool, then the paint for painting the car must be diluted to a liquid state. This will allow the coloring material to pass through the spray nozzle better. When working with a brush, the viscosity of the paint should be lower.
Also, the composition must dry quickly so that smudges and other defects do not appear on the body. To minimize purchasing costs necessary materials And at the same time not to lose the quality of the painting, you need to know how to properly dilute the paint, depending on its composition.
Composition of car paints
All automotive paints and enamels contain three basic components:
- pigment is a powder substance that gives paint the required color;
- binder– it holds the pigment and ensures adhesion of the material to the surface;
- solvent - with its help the composition is given the necessary consistency.
Different types of dyes have different physical characteristics - elasticity, density, degree of fullness, and hardness of the layer after drying.
Types of solvents
Any automotive enamel is sold in liquid form, but this does not mean that it can be used immediately. The manufacturer has already added a solvent to the paint, but just enough so that the composition does not dry out. To obtain an even coating, the material should be diluted additionally. This coating will protect the body from damage and corrosion.
Before mixing paint with solvent, you need to remember that the manufacturer has already added a certain amount. Depending on this, coloring compositions are divided into:
- highly filled;
- medium filled;
- low-filled.
Fullness is a property that determines the volatility and viscosity of the enamel; it helps to understand how much more solvent can be added.
By evaporation rate
Solvents, just like paints, come in different forms; let’s look at their main types. Depending on the evaporation rate, the following compositions are distinguished:
- Slow - they are used for work in summer period time or at high temperatures.
- Fast - the components in the composition speed up the drying process and make it possible to work with the material even in winter.
- Universal - allowed for use at average temperature conditions.
According to physical and chemical indicators
Depending on the physical and chemical characteristics There are two groups of solvents:
- Polar – alcohol, ketones, substances with molecules hydroxyl group. These materials are suitable for working with acrylic paints.
- Non-polar - white spirit, kerosene, a complex of hydrocarbon-based compounds.
In order to accurately determine how to dilute a particular paint, you should find out what solvent the manufacturer used. Match polar to polar or non-polar to non-polar.
How to dilute paint correctly
The manufacturer indicates on the packaging how much solvent needs to be added to achieve the desired consistency. For example, in the case of using acrylic, which already contains a certain proportion of activator, solvents are added in a minimal volume - the proportion is 10-15% of the total amount of paint.
How to dilute paint if it is a two-component composition? Many people use the following proportions: for 1 liter of paint they use 0.5 liters of solvent and 150 ml of hardener. How correctly the proportion is observed, the quality of the result will be.
To ensure that the paint is prepared correctly, experts recommend using a measuring ruler or flask. This is necessary to ensure that the proportions of the coloring composition, hardener and solvent fully correspond to those recommended by the manufacturer.
You should also obtain the correct viscosity of the diluted mixture - this is determined using a viscometer. You can determine the viscosity by eye - the liquid should drip and not flow in a stream.
Viscosity also varies depending on how and with what the coloring is done. So, for spray guns with a small nozzle, it is necessary that the coloring composition be liquid, but for working with a brush or roller, you can make the dye thicker.
Experts recommend that mixing containers have a strictly cylindrical shape. This is the only way to mix all the ingredients evenly and measure the quantities correctly. The best measuring utensils are: plastic jar with lid. There are markings on it that allow you to mix components in different proportions. The base is poured into the container to the required division, and then a hardener or solvent is added there. Using a measuring ruler, the components are conveniently mixed - the paint is diluted.
Often a measuring ruler is sold along with the paint, and on cans of famous brands there are always proportions according to these rulers.
In the video: how to simply dilute paint.
50% hardeners and up to 20% solvent are added to the two-component composition. The degree of dilution of the base enamel can range from 50% to 80%. It’s best to look at the instructions for exactly how to dilute the paint.
Metallic paints differ from traditional ones by the presence of aluminum powder in their composition. These are auto enamels that consist of a binder, pigment, solvent, and small metal particles. The paint should be applied in a thin and even layer - for this it must be liquid. Let's see how to thin metallic paint.
The most commonly used proportions of solvents and coloring compositions– 1:1. But this depends on the method of application of the latter. First of all, the surface is painted with a dry layer - for this you should prepare 2 parts of dye and 1 part of solvent. Then a second thick layer is applied, basically in a ratio of 1 to 1. After drying, another similar layer is applied, but thinner.
To paint a car well, you need to choose the right dye and color. There are many colors to suit every taste, and we already know how to dilute them correctly. Therefore, high-quality results are guaranteed.
Various solvents (23 photos)
