O One of the most "painful" questions arising during cosmetic and major repairs - how and how to remove or remove old paint. The task is not easy, because when creating new types of paints, their manufacture, the task of the developers is exactly the opposite - how to make the paint more stable and stronger. Nevertheless, there are ways to clean surfaces from old paint, and we will talk about many of them below.
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Video version of the article
Let's start with removing, removing from various surfaces of the coating of oil (alkyd) paints. There are three ways in which this problem is solved: thermal, mechanical and chemical, as well as their various combinations. The most common of these methods is thermal, with partial use of mechanical cleaning.
Thermal method for removing old paint (heating)
This process is carried out as follows: the old paintwork is heated to the softening temperature and in this state is cleaned off with a steel spatula. The coating is heated with a blowtorch, gas torch or industrial hair dryer.
The thermal method is simple, effective, but it has its drawbacks and limitations. For example, it will not be possible to remove paint from plastic, since most plastics begin to deform already at two hundred degrees Celsius. In addition, the use of devices creating a stream of hot fire is not always safe. In closed rooms, another factor comes into play, limiting the use of the thermal method - the release of toxic substances from paints when heated.
A big disadvantage of the thermal method of cleaning from old paint is also the fact that it can be used to clean not any surface, even if it is heat-resistant. It is not very effective when cleaning massive metal surfaces.
If the question arises of how to remove old paint from wood, then heating is irreplaceable, especially when the wood product has been covered with paint for a long time, layer by layer. When heated, such a thick layer blisters and peels off easily, leaving a clean surface suitable for re-staining without any additional preparation.
The technology of using thermal cleaning of paint is simple: with one hand they hold the heating device, directing the flame or hot air to the surface, moving the stream as the paint softens, and with the other hand, in the direction of travel, scrape off the softened paint with a spatula. The skill of working with both hands at the same time is developed literally in ten to fifteen minutes.
There are also nozzles made of metal chains, often homemade, for removing paint with a drill - this method is rough, but often convenient.
In addition to these tools, there are more specialized devices - surface grinders and grinding mills. The latter are effective when cleaning plastered, stone, concrete and other similar surfaces from paint, but are unsuitable for metal.
Surface grinders for cleaning oil compositions are ineffective, since sandpaper quickly becomes unusable, clogged with paint, but sometimes, especially if high-quality processing of small areas is required, they are not replaceable. In addition, they remove most water-based compositions well.
The technology of cleaning old paint with a power tool is even simpler than with a thermal method: the working part of the tool is pressed against the surface to be treated and, as the desired degree of cleaning is achieved, it gradually moves.
Another tool to help you remove old paint is the punch. With the help of a wide nozzle-spatula, often homemade, you can remove old paint from concrete bases, knocking it down with a perforator. The disadvantage of this method is that, together with the paint, the base itself can be damaged, therefore this method is more suitable for removing paint from durable concrete. Together with the paint, putty and plaster are well removed in this way, at →.
Sandblasting method of removing, removing old paint
Another common method of mechanical cleaning from old paint is sandblasting. The principle of sandblasting is that a jet of air or water is sent to the surface to be cleaned under high pressure, to which abrasive particles (most often ordinary sand) are added. Grains of sand, hitting the surface at high speed, perfectly clean it not only from paint, but also from rust, from various other persistent contaminants.
The disadvantages of the sandblasting method include the relatively high cost of equipment and the need for certain skills to maintain the fixtures and perform the work itself.
It so happens that you need to carry out the restoration of a product. In this case, you have to remove the old coating. This operation can be performed in different ways:
- mechanically remove the paint layer;
- by thermal (thermal) method, acting on the painted surface, they achieve the melting of the paintwork;
- chemically active solvent destroys long molecules of the polymer film, in the future, it remains only to help remove with brushes or spatulas to remove paint residues.
Sometimes you have to spend a lot of time to remove the paint system. It is scraped off in small pieces, constantly returning to the place where the procedures for removing the worn-out layer have already been performed.
How to choose a method for removing paint from metal
Before you get started, you need to prepare. Estimate the amount of work. For example, in order to mechanically remove the old paintwork from the fence, you will have to calculate the costs of working time (Table 1).
Table 1
It remains to consider the time norms for chemical removal of the old coating (Table 3). All calculations are made by analogy with the previous ones. The difference is only in the nominal time spent per unit area.
From the above calculations, it can be seen that the least labor costs will be with the chemical method of removing the old coating. It seemed that one could rejoice. However, for thermal work, special equipment will be required, as well as consumables in the form of liquefied gas. Gas in a cylinder is inexpensive, but you still have to buy it. In the absence of burners, they will also have to be purchased.
For work related to chemistry, you will have to purchase chemicals, as well as additional tools to carry out the work. This will be the cost of purchasing chemical reagents.
Mechanical labor can also have different levels of mechanization. You can stupidly take a scraper and start cleaning. You can also pick up an angle grinder, along the way, use mechanical brushes and flap wheels to carry out the work. You will also need extension cords to supply the required voltage to the work site.
To solve the problem by different methods, they should be considered in more detail.
Mechanical cleaning from old paint
You can pick up a scraper and start peeling off the cover (fig. 1). Labor productivity will be close to zero. In some places, it will not be possible to remove even parts of the layer in this way. The adhesive forces are retained. It will not work at all. You will have to use a hammer and a chisel to mechanically cause destruction in the layers.
But this method is applicable if you ensure the preliminary destruction of bonds inside the paint coating. It is used as an additional effect.
Table 4 shows mechanized paint removal methods. Here, the performance is already higher.
When carrying out technological calculations, the costs of purchasing consumables are specified. Data for calculations are taken from the technologist's reference books. The grain size and tool life are selected.
Calculations for the needs of the tool are summarized in table. 5. To find out the cost of consumable tools, you will have to multiply the price of each by the quantity. The data obtained by calculation are usually brought to an integer value. Additionally, they acquire some stock.
Finally, the costs of mechanical cleaning of old paint are carried out by determining the cost of labor (when hiring a worker to perform this type of activity). Here the number of hours is multiplied by the cost per man-hour.
Since the cost of labor in different regions may vary. You can hire workers of different qualifications, the amount of financial costs will be different.
The tools can also be purchased from wholesalers or retail chains. The differences will be smaller, but still have to be taken into account.
Thermal cleaning of old paint
To warm up the paint and varnish layer, a stream of hot gas must be supplied to its location. It can be obtained in different ways:
The cleanest and safest is to use an electric hair dryer. Modern tools allow you to work in several modes, which is convenient for the user. However, the flow rate from the hair dryer is relatively low. There are temperature restrictions (no more than 600 ° C). Therefore, building hair dryers are used for relatively small surfaces.
Relatively recently, the production of cans with a volume of 0.8 ... 1.0 liters of liquefied gas has been launched. Special burners are produced for them. The flame temperature can reach up to 1600… 1800 ° С. Using such devices, they achieve rapid heating of the painted surface. Labor productivity is increasing.
Modern burners equipped with a piezo ignition make it possible to turn off the gas supply in order to remove it with a scraper after heating the paint layer. Then it is not difficult to re-ignite the gas, proceeding to firing the next surface.
Powerful gas burners connected to 50 liter cylinders allow you to process several square meters in an hour. These are the most productive devices. When using them, at least two people work. One operates the burner, the other removes the paint.
Blow torches use gasoline to keep them burning. Before putting them into operation, you have to spend time firing up and warming up the nozzle. The performance of blowtorches is also quite high. The flame has a temperature of up to 2000 ° C. Therefore, when using this tool to remove the coating, its high fire hazard should be taken into account.
When working outdoors, the thermal cleaning method is justified by high labor productivity, as well as a relatively cheap consumable. Gas and petrol are inexpensive for most craftsmen.
When determining the cost of work, perform the calculations described above. The total costs are then compared against mechanical paint removal.
Chemical removal of old paintwork
When exposed to chemicals on the painted surface, the layer dissolves. After softening, the bonds between the individual parts of the paint are weakened. It is possible, with little mechanical force, to clean off the swollen coating.
If it is possible to supply water under pressure, then the chemically destroyed layer is simply washed off. It is convenient to use pressure washers here. They give out a jet of water with air. Water literally "boils" interacting with the surface. Old paint is fairly easy to wash off.
Aerosol can Aerosol cans are very convenient to use. When using them, you need to vigorously shake the can several times, and then direct a stream of liquid to the surface. After a few minutes, the old coating will swell. It remains only to remove it from the surface.
Many users prefer to use this method of chemical paint removal. You don't need to do anything here.
When using acid-based washes, the respiratory system and eyes must be protected, and gloves must be worn on the hands that do not dissolve in acids.
These washes are applied with brushes or brushes. The liquid is pre-poured into a plastic container. Some masters use spray guns, but you should be aware that such solutions can dissolve not only paint, individual elements of the spray gun can also dissolve in strong acid.
At car repair enterprises, before carrying out the repair of individual units, it becomes necessary to remove the old paint. Special anti-paint gels have become widespread here, which quite quickly dissolve even car enamels on an alkyd or acrylic base.
In factories where it is necessary to carry out paintwork with the use of powder paint, they use "Antikras-Sprint". When performing work, you have to hang products and parts on hooks. Then powder paint is sprayed on. The prepared elements are sent to the reflow oven. At the exit from the oven, the products receive an even dense layer.
But the hooks themselves are also dyed. Therefore, paint is washed off from them, applying "Antikras-Sprint".
When preparing for paint removal, the consumption of washes should be calculated. Having decided on the quantity, they also find the total cost of performing work with the help of chemical components. In the future, they compare the results for all types of work. And they decide which one to give preference to.
Video: How to remove old paint from walls
Removing oil paint from walls is a long and laborious job
Anyone who has tried at least once to clean the walls of old paintwork knows how difficult it is to remove oil paint. Even if in some places it is swollen and falls off by itself, in some areas it is held so tightly that it does not lend itself to the action of a scraper or an iron brush.
However, there are several ways to remove old oil paint from the walls, and their choice depends on the further intended finish, your willingness to spend time or money.
And is it always necessary to do this? The question is very simple, as is the answer to it.
Let's start with where you can find such a covering on the walls now? Is that in old apartments, in which the "Soviet" decoration is still preserved: the walls, painted from below with a dark color and light (or whitewashed) on top. But this is not so important.
It is important what you are going to do with them next:
- If leveled with plaster (see Aligning walls with plaster according to all the rules), putty, tiled, painted or wallpaper, then it is imperative to clean off the coating, because building mixtures and adhesives will not "stick" to it, or the adhesion will turn out to be very unreliable. Flaking of the new coating may result.
- If it is planned to finish with plasterboard, clapboard, wall panels or any other materials attached to the lathing, there is no need to remove the paint.
Therefore, it is advisable to make a decision on further finishing in advance, before removing the oil paint from the walls, spending a lot of time and effort. And even if it is necessary, the method of dismantling the old coating is also often selected depending on the type of new coating.
What tools will come in handy
The tools for removing paint from the walls are used in a variety of ways. That is, everyone can find what will ideally fit their budget and situation as a whole.
Depending on the type of paint and how it is removed, the following materials and tools may be needed:
- Building hair dryer - they are useful for the thermal method;
- Electric drill;
- A spatula or scraper is a versatile tool;
- Water;
- Personal protective equipment such as gloves, respirator.
- The liquid with which the varnish is removed, well, brushes or a roller to it. With such a tool, you need to be extremely careful as it can be toxic and cause allergies.
Methods for removing oil paint
Each method described below has both advantages and disadvantages, including one common one: in any case, it will take a lot of effort and time from you.
Mechanical
Physically, this method is the most laborious and time consuming, but it does not require financial costs and does not harm health. The main tool of labor is an ordinary ax, which you will have to wield with your own hands. This requires considerable physical strength.
This method is ideal if:
- After cleaning, you will level the walls with plaster;
- Or tile it.
Both plaster and glue solutions adhere best to a rough surface, and after processing with an ax, it becomes just that. The essence of cleaning the wall from the oil coating is that it is literally cut off from the surface.
This is done like this:
- First, with a sharp ax, frequent notches are made over the entire area to be cleaned.;
- Then the wall is abundantly moistened with water using a spray bottle or wet rag;
- When the water is absorbed, use the same ax or hammer and chisel to clean off the coating holding the tool no longer at a straight line, but at an acute angle to the surface.
Advice. It is best to wet and clean small areas so that the water does not dry out.
This method is also chosen if the work is performed in a room without ventilation, which cannot be actively ventilated. A lot of dust is formed, but a regular gauze bandage will help protect the respiratory organs from it.
Chemical
It is physically much easier to wash paint off the walls than to cut it down (see How to wash paint off without problems). And faster. And this is quite feasible, since there is a special tool for removing oil paint from walls, and more than one. Often it is called a wash.
In its composition, it contains acids, solvents and other chemicals that soften the coating, which is then easily removed with a spatula or metal scraper.
As you already understood, the washing process is not at all like removing dirt from the surface with water and a rag, since the solution is very aggressive, and you need to work with it, strictly observing the technology:
- The solution is applied to the surface with a roller or brush in one direction;
- After the specified time has elapsed, when the coating becomes soft, it is removed along with the applied agent with any convenient tool;
It is very convenient to work with a metal spatula
- The procedure sometimes has to be repeated to achieve the desired result. As a rule, re-washing is necessary if the paint is applied in several layers;
- At the end of the work, the mixture of paint and solvent must be disposed of, preventing it from getting into the ground or household sewers.
The biggest drawback of this method is the danger of poisoning with volatile substances or getting a serious burn of the skin and mucous membranes. Therefore, it can only be used in rooms with a powerful hood or with the possibility of good ventilation. But even in this case, the smell can last for quite a long time, so you cannot live or just stay in the room for a long time during the renovation. Especially children and people with health problems.
Advice. To protect yourself, work should be done in a respirator, protecting your eyes with special glasses, and your hands with gloves. It is also advisable to wear a suit with long sleeves and pant legs.
The second serious disadvantage is the high price of the product, which significantly affects the wallet if a large area is to be processed. In addition to ready-made chemicals, you can use less hazardous substances: lime, soda ash, liquid glass.
Their use for walls is difficult, but oil paint can be removed from the floor without problems:
- It must be moistened abundantly with water, covered with a continuous layer of soda and covered with sackcloth for a day, constantly wetting it during this time. The swollen paint will be easily removed the next day with a spatula.
- Quicklime, which is mixed with soda ash in a 3: 1 ratio, will help speed up the process. thick slurry is also applied to the surface and kept for 12 hours.
- But the walls can be greased with liquid glass and allowed to dry. When this happens, the silicate film formed will peel off the surface along with the old paint.
Thermal
Oil paint softens not only under the influence of chemicals, but also under the influence of high temperatures. If the coating is warmed up well, it can be scraped off with a spatula. This can be done with a construction hair dryer.
In this case, the work is carried out simultaneously: a small area heats up and immediately frees from the paint until it hardens again.
Cleaning with a hair dryer
In the absence of a special tool, you can use a regular iron, heating the painted surface through foil.
It is important. The method cannot be used in areas with electrical wiring, as well as on surfaces that are afraid of heating (plastic, PVC).
The heating method could be considered the cleanest and safest if the paint did not emit toxic substances when heated. Therefore, as in the case of the wash, the instruction allows its use only in ventilated rooms and subject to the use of respiratory protection.
But you cannot use a blowtorch, gas torch or any other source of open fire to soften paint - it is fire hazardous. Especially if the base is wooden.
Mechanized
Mechanized methods speed up the process, but create a lot of dust and dirt. Therefore, here it is worth recalling the need to use a respirator or gauze bandage on the face.
A grinder or a drill with special attachments is used as the main tools:
- Grinder attachments - a wide abrasive wheel or a round metal brush. To reduce the amount of dust, it is recommended to take an assistant with a vacuum cleaner if it is not possible to use a specialized tool with a built-in vacuum cleaner.
- On a drill or perforator, you can fix a crown on a brick.
- Another tool for removing paint is the paint chain, which is also attached to the drill. If you cannot find it, you can use any chain with thick links (at least 5 mm in cross section). There should be an odd number of links: 11, 13 or 15, so that after fixing the central link, the chain length on both sides is the same - for balance. For the same reason, if the links are damaged on one side, they are removed from the other, until there are three of them left on each side. In this case, the chain is changed to a new one, since it will be inconvenient and traumatic to work with a short one.
Note. If you are right-handed, the drill with the chain should be turned on by rotating it to the left, if you are left-handed - to the right.
Conclusion
Thermal and chemical methods of cleaning are less laborious, moreover, they make it possible to do without serious damage to the surface of the base and subsequently save on leveling solutions. But they are also the most dangerous to health. Therefore, think carefully before choosing any of the proposed methods.
Perhaps the video in this article will help you with this.
Removing old paint by hand from a wooden surfaceBefore painting any surface, preliminary preparation must be done. It includes removing dirt, cobwebs, insects from the surface, as well as removing paint, sanding (for wood surfaces) and putty.
The most important step is to remove the surface coating. Leaving old paint contributes to the appearance of cracks, peeling of the new coating, and a violation of the aesthetic appearance. Let's take a look at the most common paint stripping methods that you can use on your farm:
- thermal;
- chemical;
- mechanical.
The application of one of the methods depends on the type of paint applied, as well as on the material of the surface to be cleaned.
Thermal method
The most effective method for cleaning wood surfaces from paint and varnish is the method of heat treatment. With the help of a hair dryer or a burner, the old surface is heated to the melting point. The paint softens and flakes off, after which it can be easily cleaned off with a hand spatula. The advantage of this method is that even thick layers of paint can be removed quickly and efficiently.
The processing method is suitable only for wood, and in some cases for metal. Ineffective for plastic, the latter begins to melt and deform at high temperatures. This method is of little use for processing painted concrete, stone or plaster surfaces. A significant drawback is the release of volatile toxic substances when the paint is heated.
Chemical method of removing paint
You can also remove old paint with special means, which include chemical solvents. They are produced to remove a specific coating and are based on acids, alkalis and organic polar substances such as acetone or gasoline. There are also solvents with a universal composition, but their effectiveness is lower.
After applying the solvent to the surface, it should be left for 15-60 minutes. The time depends on the type of old paint and the thickness of the applied layer. The required contact time with the surface must be indicated on the package. During this time, the old paint will begin to soften and can be easily removed with a hand spatula.
The chemical method is suitable for cleaning most surfaces:
- wood;
- metal;
- plastic and linoleum;
- MDF and glass.
Method of removing paint by mechanical action
Mechanical methods of stripping paint include cleaning with hand or power tools. The most common tool for removing paint from large surfaces is a grinder or angle grinder. If a grinder is used, a special wire brush (brush) is fixed on it instead of a disk. You can also use a drill with a metal tip. This method is suitable for cleaning wood and metal from oil paints.
To clean concrete, stone, plastered walls from water-based paints, surface grinders with coarse-grained emery paper, with a grain size of 250-600 microns, are used.
The manual method of removing paint with a spatula or scrapers is also referred to as a mechanical method. This process is quite long and laborious, but the most affordable. Removing the paint by hand will not result in a completely cleaned surface, so use it in combination with other methods, or at the stage of finishing preparatory work. The advantage of the manual method is the ability to remove any paintwork.
Removing old oil paint from walls is a rather complicated and time-consuming process.
In some areas, the coating swells and falls off, but in some places it adheres very tightly and does not always lend itself to the action of an iron brush or scraper.
How to remove old oil paint from walls at home? The best ways to do this are discussed in the article.
The amount of time and effort spent on removing the composition from the surface directly depends on the selected dismantling method. The large number of superimposed layers makes cleaning much easier.
The time spent removing the paint depends on the material on which the composition was applied. With porous, loose plaster, paint is removed more easily, but you have to suffer.
Exists . You can clean the surface with:
Mechanical impact
The process of cleaning walls from oil paint by means of a mechanical method is the longest and most laborious, but does not require any financial costs.
This method is ideal for the subsequent tiling of walls or leveling them with plaster, since adhesive and plaster solutions adhere perfectly to a rough surface.
The essence of the mechanical method of cleaning walls is to scrape and chop paint off the surface of the walls.
How to remove with an ax?
To clean the walls with this method, the main tool is an ordinary ax.
The cleansing process takes place in several stages:
To prevent the water from drying out, it is better to moisten and clean the surface in small areas.
How to clean with a spatula or chisel?
This method is suitable for removing paint in hard-to-reach places and corners, as well as with a lagging oil composition from the walls. To facilitate the work, you can use a hammer, which should be hit on the handle of a chisel or spatula. The surface to be treated must also be moistened with water.
When working in this way, the tool should be sharpened periodically, as it quickly becomes dull during such work.
The mechanical method of removing oil paint from a surface requires physical stamina and extreme care when working with construction tools. However, this method does not require any financial investments and is safe for health.
Thermal method
The oil composition applied to the walls softens significantly under the influence of high temperatures. If the surface is thoroughly heated, the paint can be removed with an ordinary spatula.
For cleansing in a thermal way, use a construction hairdryer.... Simultaneously expose a small area of the surface to high temperatures and remove the paint until it hardens again.
In the absence of a special tool, you can use a regular iron. The surface should be heated through a sheet of foil.
The thermal method is not recommended for use in areas with electrical wiring, on surfaces made of plastic and PVC. Wall treatment should be carried out in rooms with good ventilation, using protective equipment for the respiratory system. Under the influence of high temperatures, the paint releases harmful substances.
It is strictly forbidden to use a blowtorch, gas torch and other sources of open fire to soften the oil composition, as it is unsafe and can lead to a fire. Especially if the surface is made of wood.
Electromechanical
The principle of this method of paint stripping is similar to the mechanical one. Instead of an ax or chisel, they use a power tool, which greatly facilitates the work.
The oil composition is removed using a drill, perforator or grinder with special attachments: an abrasive wheel, a metal brush, a brick crown.
The order of work when using the electromechanical method:
The advantages of this method are quick cleaning of large surfaces, minimal expenditure of physical strength.
The disadvantages of the electromechanical method include:
- loud noise when working with the tool;
- a large amount of small debris and dust;
- inability to remove paint in hard-to-reach places;
- the need for a sufficient supply of nozzles, as they wear out quickly.
How to wash off with chemical compounds?
Removing the old finishing material with chemical solutions is much easier and easier than scraping with construction tools.
There are many special tools available for. They contain solvents, acids and other preparations that soften the coating. After applying the mixture to the wall, the paint can be easily removed with a scraper or spatula.
The removal process assumes strict adherence to the technology:
Sometimes you have to resort to re-washing. Painted walls in multiple layers may not be easy to clean the first time.
After completion of work, the removed paint with a chemical composition should be disposed of. Do not allow the mixture to enter the domestic sewer or the ground.
The big disadvantage of using the chemical method is:
- danger of getting poisoned by volatile substances,
- get a burn of the mucous membrane, skin.
It is necessary to carry out work using special washes for oil paint in protective glasses and gloves. Chemicals should be used only in rooms with good ventilation. The smell from drugs may not disappear for a long time, so you should not stay in the room being repaired for a long time.
Another significant disadvantage of the chemical method for removing the oil composition is the high price of the drug that is applied to the surface. Especially if it is necessary to process large areas.
Features of removing old paint
In order for the process of removing the old composition to be easy, it is necessary to choose the correct cleaning methods. With a competent approach to work, the paint will lag behind the walls quickly, and the surface will not be damaged. Always take into account the type of surface to which the paint is applied.
It is much easier to remove paint from walls if it is applied in several layers. If the composition is applied in one layer on a concrete surface, then there will be a long painstaking work. In this case, chemical paint removal is best.
The choice of cleaning method depends on the presence of a layer of plaster under the composition... If not the wall itself is painted, but the bonding layer, then the removal process will be much faster. If there is plaster on the wall, a mechanical method of removing paint from the surface is best. Before starting a new wall decoration, they should be leveled.
Frequent mistakes in the cleaning process
With the wrong approach to removing oil paint from the walls, you can harm your own health, as well as spoil the surface to be cleaned.
In no case should open sources of fire be used in the thermal method. dismantling paint.
When using a chemical cleaner, the room must be well ventilated or well ventilated. Improperly selected paint scraping tools can damage the surface to be treated.
Do not neglect protective equipment in the process of performing work:
- glasses,
- gloves,
- respirators.
Subject to all safety rules, the likelihood of harm to your health is excluded.
When using the thermal method, heating the wall from the bottom up will be most effective.... A well-heated strip can be easily removed with a spatula. The composition will melt under the influence of high temperatures, therefore, a cloth should be used to clean the spatula.
Do not use chemical washes and clean the paint with solvents in multi-storey residential buildings. Poisonous fumes from drugs can adversely affect residents of neighboring apartments.
Related Videos
Video review of the main ways to remove oil paint from walls:
Conclusion
Chemical and thermal methods for dismantling the old oil composition from the walls are less laborious, do not damage the surface to be cleaned, which subsequently allows you to save on putties and other mixtures.
However, such methods are the most dangerous for human health. That's why before starting work, you should carefully consider which method will be most acceptable.