How to properly paint a metal surface - technology

Metal is used to make a variety of parts. This is a reliable material, but it is not resistant to a number of environmental factors. Therefore, in order to create a decorative coating, as well as obtain additional protective functions, they often resort to painting the metal. The final result will depend on the choice of product and the correct execution of the dyeing technique. Next we will talk in detail about how to paint metal so that the coating does not peel off.

The essence and features of the method

The first paints for metal surfaces performed only the function of changing color. Such products could not stay on the material for a long time, for this reason, manufacturers decided to produce substances that, in addition to painting, serve as protection against the formation of rust and other negative factors affecting the strength of the coating.

Today, the market offers a wide range of coloring agents that can cope with these needs. There are different methods for painting iron; rollers, brushes, and a spray gun can be used.

Today, the market offers a wide range of coloring agents that can cope with these needs.

Rust paint: features and application

Metal is susceptible to corrosion; upon contact with air or water, it oxidizes and becomes rusty. There is a classic way to get rid of it: you need to clean off the rusty coating, prime and paint the surface.

What paint should I use to paint metal on the street or at home if it is not possible to remove the rust? For such tasks, manufacturers offer special rust paints. They have the following properties:

• They are applied directly to rust; there is no need to clean the metal first.
• Does not require preliminary priming.
• They form a protective coating that lasts for several years.
• Dries quickly.
• Available in different shades.

When choosing what paint to paint rusty metal with, pay attention to the restrictions on the use of such compounds. Generally, they should not be used in areas that reach high temperatures or come into contact with potable water. Despite these limitations, such compositions are very popular - they are indispensable, for example, when processing parts with complex configurations or hard-to-reach surfaces.

Is it possible to paint metal?

Metal painting can be chosen as a treatment only if you know for sure whether it can be used. Often metal materials are made from black iron, its surface is not protected from the effects of liquids, for this reason, over time, water leads to corrosive formations. There are specialized anti-rust products on sale, as well as paints.

Galvanization has already received protection from these influences, but you can extend the shelf life of the material by additionally painting it.

Metal painting can be chosen as its treatment.

Surface preparation

First of all, we prepare the surface. To do this, remove traces of corrosion and old paint. If this is not done, the applied layer of material will not adhere well and the coloring will become useless.

Surface cleaning is done in one of three ways:

1. Mechanical. This is done using a wire brush or abrasive discs. It is recommended to use this method only for surfaces where rough processing is acceptable. Important note: mechanical cleaning should only be carried out with appropriate respiratory protection from metal dust.
2. Sandblasting. Cleaning is carried out using special equipment that, under high pressure, directs streams of sand grains towards traces of corrosion, old paint and scale. The sandblasting method is effective for cleaning surfaces even in hard-to-reach places. The only drawback of this method is the high prices of equipment.
3. Chemicals. Removing rust, scale and old paint layers can be done using chemical reagents. The chemistry reacts with the elements being removed, destroying them. After treatment, all that remains is to remove the remaining rust and paint with a cloth.

Regardless of the chosen method, you need to finish the job by finishing the surface - it should be as clean as possible.

After cleaning the metal, we begin priming. This increases the adhesive qualities of the surface and provides additional protection for the metal from moisture. You can start painting only after the primer has completely dried.

How to calculate paint consumption

Before painting a metal product, you need to calculate the amount required for the job. The manufacturer always writes the average product consumption on the packaging of the product. The indicator may vary somewhat; it is influenced by the application tool, surface structure, coloring agent, and the presence of complex elements on the object.

The manufacturer always writes the average product consumption on the packaging of the product.

Metal painting technology

The technological process is divided into several successive stages, which allows you to achieve the best results.

Tools and materials

First of all, you need to prepare the necessary tools and materials:

• Coloring composition.
• When processing sheet products manually, a roller is used; for complex or hard-to-reach areas, brushes are used; when using a mechanized method, a spray gun is used. If you need to paint a large area, it is very difficult to do it with hand tools. But you need to take into account that only a composition of a certain viscosity can be applied well with a spray bottle.
• Primer mixture. When working with a regular base, a simple metal solution will do. If the product is made of non-ferrous materials, then the appropriate primer is selected. If rust is present, a converting primer will be required. Its peculiarity is that it interacts with the damaged structure and turns it into a protective layer.
• Separate container for paint. This can be a roller or brush container to make the process easier.

Tools and materials for painting

Attention! Be sure to read the instructions provided by each manufacturer. Particular attention is paid to the conditions for performing work. So, the minimum permissible temperature is +5 degrees with a humidity not higher than 80%!

Preparing metal surfaces for painting

This process requires a responsible approach; any shortcomings will be noticeable. Correcting problems that arise due to poor preparation is extremely difficult, and sometimes impossible.

Algorithm of actions:

1. The base is cleaned of dust and dirt, the remnants of the old decorative layer are completely removed. When working with metal, it is better to avoid applying new paint to old paint, even if they match.
2. An important step is degreasing, which improves adhesion. When working outdoors, it is necessary to protect the surface from dirt. The first wash is carried out using a solvent or white spirit: the entire area is treated, special attention is paid to hard-to-reach places. The next wash is done with a warm soapy solution, which is then thoroughly removed with plain water. The result should be a clean and dry coating.

   Degreasing occurs sequentially: stage 1 - use of a special degreaser, 2 - soapy water, 3 - plain water

3. If there are defects (cracks and depressions) that spoil the appearance, puttying is carried out. All treated areas are pre-treated with anti-corrosion compounds. The putty is applied selectively, exclusively to the desired areas. The mixture is carefully distributed and leveled, and after drying it is sanded. The result should be a single plane without traces of repair.
4. If rust is present, it is removed; in case of severe damage, a converter is used. It is applied to a surface that has been cleaned of major traces of corrosion. Due to phosphoric acid, a reaction occurs during which a protective film is formed.
5. Minor damage can be removed by sanding and stripping. The need to use a primer depends on the type of paint chosen and the type of coating. For example, galvanized steel should not be primed.

The preparation of the metal surface can be considered complete after all actions have been completed and the base has dried.

How to paint metal products correctly

Painting methods depend on the tools; a combination of devices is allowed.

Roller painting

The roller is convenient to work on large and flat surfaces. The technology is as follows:

1. The composition is pre-diluted, and a suitable substance is selected as a solvent. This procedure is necessary for easier distribution.
2. The paint is poured into a convenient container. The roller should be immersed with its wide part, and not sideways. The tool must be extremely reliable and not leave lint behind.
3. The process begins with the selected area. It is better to move from one edge to the other, this will avoid visible transitions.
4. The moistened tool is placed on the surface, after which rolling begins. The first movements go in the vertical direction: from bottom to top and back. An area two or three times the width of the roller is immediately grabbed. The pressure should be minimal and gradually increase.
5. After the composition is transferred to the surface, the movements change to horizontal.

A roller is an affordable and quick way to paint, but this tool is more suitable for straight and even surfaces

The key to successful work is the systematic distribution of the material without too thick areas. The number of layers applied varies from 2 to 4.

Important! Each subsequent layer is applied only after the previous one has thoroughly dried. At the same time, artificial acceleration of the process is prohibited.

Painting with a brush

This is a rather monotonous task, which is carried out on complex or embossed parts of the product.

The brush is ideal for hard-to-reach places and small areas to be painted.

If the mixture is too viscous, then dilute it a little. You don’t need to dip the bristles completely, but 1/3 of the way, this will avoid drips; shake off the excess by tapping on the edge of the container. Movements must be unidirectional. The paint is applied to the coating with the first strokes, and rubbed with subsequent strokes. The number of layers applied depends on the type of surface.

Complex structures are painted with thin brushes, using a minimal amount of solution. This will prevent the appearance of frozen drops.

Using a spray gun

Since the absorption of metal is not very high, using a spray bottle requires experience. If not, you need to practice.

Applying paint using a spray gun

Recommendations for work are as follows:

1. Spraying occurs without stopping. The first movements should be smooth and slow. The layer is laid parallel.
2. After the initial coating, the process speeds up, treating the same area in different directions. It is important to maintain the same distance.

This device makes DIY work much easier. With some skill, even difficult areas can be painted.

On a note! If you want to get a surface with an antique effect, then you resort to various methods. Bronze staining and glazing are considered the simplest.

Advantages and disadvantages of the method

Painting metal surfaces has both positive and negative sides. The choice to paint a material or not should be made based on knowledge of them. The advantages are noted:

• The coating takes on the selected color. There are many options, from standard colors, to gold, bronze, silver, etc.;
• Availability of the method, no need to purchase many tools and materials;
• Easy to carry out, no special skills required;
• Get additional protection. This is especially important for items located outdoors; in winter and summer they are exposed to different weather conditions.

The disadvantages include the following points:

• Most paints emit a pungent odor that lingers in the room for a long time;
• The powder method can only be carried out using special equipment;
• Not all colorants can provide anti-corrosion protection, which should be taken into account when choosing.

Almost all shortcomings can be eliminated if you choose a quality product.

Painting metal surfaces has both positive and negative sides.

Types of paints for metal

Oil paints

Materials based on drying oil or other oils have been used for painting metal for a long time. The main advantage of oil paints is their low price. The main disadvantages are low elasticity and abrasion resistance.

The finished coating fades quickly enough in the sun and is afraid of temperature changes. Therefore, oil compounds are not suitable for outdoor work. Most often they are used indoors for surfaces that bear light loads.

Alkyd enamels

Enamels based on alkyd resins are one of the most popular types of metal paints for exterior use. They can also be used indoors to paint metal, wood and stone surfaces. Alkyd coating is stronger than oil coating and can have any shade, be glossy or matte.

Alkyd compositions are characterized by relatively rapid drying. They are easy to work with - provided simple safety requirements are followed, this task can be completed by a non-professional. The disadvantages of alkyd enamels are the need to use solvents and the relatively short service life of the coating.

Acrylic compounds

Painting with acrylic paints allows you to obtain a durable coating that is not afraid of temperature changes, does not crack in the sun, protects against corrosion and lasts for several years. Therefore, it is one of the best metal paints for exterior use. Another advantage of acrylic materials is environmental friendliness. Thanks to this, they can also be used at home - for example, for heating radiators or as decorative paint.

The disadvantages of acrylic compositions include some fading of colors - other types of paints may be brighter. Another disadvantage that can be significant when choosing paint for metal is the relatively high price. Acrylic sets quickly, but it takes several days for the composition to dry completely - during this time it is advisable to protect the coating from damage and dirt.

Nitro paints

Materials based on cellulose nitrate have been developed for painting automobile bodies. Gradually they began to be used in other areas, including for processing metal structures in everyday life.

Here are some positive properties of nitrocellulose-based metal paints:

• Aesthetics: you can get bright colors, mirror glossy shine.
• Fade resistant: color lasts for a long time.
• Possibility of outdoor use.
• Fast drying.

Most often, nitro paints are sold in cans. They are sprayed onto a primed metal surface in a thin layer. The material is toxic, so it is recommended to work in respirators.

Powder formulations

When choosing which metal paint is best, it is difficult to ignore powder formulations. They form a very durable protective layer that lasts for many years. However, in everyday life, powder coating is almost never used due to the complex application: the powder must be preheated. Using this technology, metal elements are often painted in a factory setting.

Preparatory activities

To obtain the desired result, the painting process must be carried out with surface preparation. And also the choice of paint should be done with special attention. The combination of carefully performing all stages will help you get an excellent result with your own hands.

To obtain the desired result, the painting process must be carried out with surface preparation.

Paint selection

Before painting metal, it is necessary to analyze what functions the painting will have to perform, in what conditions the item will be used, and the type of product: fence, car, doors or other items. Then it will be easier to choose a coloring composition, and the result will be good.

Popular and common compositions suitable for painting have been described above. Here we will talk about the types that differ in obtaining special properties on the surface:

• If there is an area with rust, you can mix epoxy with chemical components, this will create a coating that delays the further spread of the lesion and a barrier against new formations;
• Hammer paints are a subtype of different paints. They are suitable for items used outdoors and create strong protection from external influences;
• Primer enamel is one product that includes the characteristics of a primer mixture and paint;
• Nitro paints are highly toxic, so they can only be used outdoors; they are produced exclusively in cans.

Hammer paints are suitable for items used outdoors and create durable protection from external influences.

Materials and tools

It is better not to interrupt painting; for this reason, make sure that all the necessary tools and materials are available in advance. You will need to prepare the following items:

• A primer solution that will suit the task at hand;
• Container for coloring composition;
• Roller, brush. The second is necessary for painting hard-to-reach places; a roller is more suitable for working with large products. You can choose a spray bottle.

It is better not to interrupt painting; for this reason, make sure that all the necessary tools and materials are available in advance.

Surface pre-treatment

To prevent painting from highlighting defects that were on the surface, you need to get rid of them. Therefore, a preparatory stage is carried out, including the following actions:

1. All dirt is removed. If there is an old coating, it is better to eliminate it.
2. A degreasing agent is applied, all areas should be treated, and the surface is washed again.
3. After the base has dried, a putty mixture is applied to obtain a smooth base.
4. Next, the rusty layer is removed, and a rust converter can be applied.
5. Small flaws can be removed by sanding.

If there is an old coating, it is better to eliminate it.

Advantages of liquid painting

Despite the emergence of more modern methods of painting metal, painting with liquid paint is still in widespread demand among customers. The main reason for its popularity is its attractive price-quality ratio. At a minimal price, the client is guaranteed a high-quality and durable result. The main disadvantage of the method is the low productivity due to the use of hand tools - brushes, rollers or spray guns. But unlike mass production, when fulfilling small-volume orders, this drawback is not significant.

Oil, epoxy, acrylic, alkyd, rubber and other paints are used to paint metal surfaces.

Among the advantages of painting metal with liquid paints:

• low cost;
• Dries quite quickly;
• wide selection of colors;
• good protective properties;
• Possibility of painting both small parts and large surfaces.

Depending on the composition of the alloy and the characteristics of the metal part, the painting process can include up to 8-10 stages. Main stages:

• mechanical cleaning of the surface from dirt, scale, unevenness, traces of previous painting, etc.;
• degreasing with alcohol or gasoline solutions to remove grease and oil contaminants;
• passivation - treatment with a chromate solution to create a protective layer of oxides against rust on the metal surface;
• priming to improve the adhesion (adhesion) of the paint layer to the metal surface;
• direct painting;
• drying.

The price of powder (liquid) painting of pipes and sheets in meters (square) is calculated based on the depth of the part and the volume of the order. When placing an order from 30 sq.m., a discount is provided.

Coloring methods

Depending on the chosen application tool, the painting technique will vary. Following all the nuances will help you get an even coating.

Using a roller

The roller is used for large surface areas; it is leveled before the process, otherwise painting will highlight all the defects. Proceed as follows:

1. The coloring solution is being prepared.
2. It is better to use a special ditch for painting, into which the roller is immersed for paint impregnation.
3. Start coloring from one edge, moving to the other.
4. Movements are made from top to bottom.
5. This way the entire surface is painted; it is advisable to apply two layers of paint, each one should dry before applying the next.

The roller is used for large surface areas; it is leveled before the process, otherwise painting will highlight all the defects.

An ordinary brush

The technology of painting metal surfaces with a brush is more complicated; it is better to immerse it halfway in the container with paint to avoid smudges. The first stroke applies the main composition, the rest serve to distribute it on the material. Each application should be done in the same direction as the previous one. How many layers will be made is determined visually.

Each application should be done in the same direction as the previous one.

Using a spray gun

The spray gun requires certain skills from the master, especially when it comes to metal that does not adhere well to compounds. Advice from professionals can help you cope with the task:

• Spraying is done at a time and evenly;
• They move slowly and smoothly;
• The distribution is done in parallel;
• The second layer can be applied in any direction.

The spray gun requires certain skills from the master, especially when it comes to metal that does not adhere well to compounds.

Application methods

To apply paint you can use:

1. Paint brush. Suitable for painting small parts. You can find brushes of different sizes on sale. The bristles can be natural or synthetic. For access to hard-to-reach places, the tool is equipped with an elongated curved handle.
2. Roller. Suitable for painting large flat surfaces.
3. Sprayers. The second name for the spray gun. A compressor is used to operate them. The coloring composition is supplied under pressure. The equipment is used by large enterprises, car repair shops, carpentry, and blacksmith shops.
4. Containers for dipping metal workpieces. This method makes it easy to paint parts with complex shapes.

Modern technology - powder coating of metal. The blanks are placed in a closed spray booth and covered with a layer of paint. Its particles receive a negative electrical charge and are attracted to the working surface, creating a dense, uniform layer. After applying the powder, the workpiece is placed in an oven so that the decorative layer bakes and becomes monolithic.

Paint brush (Photo: Instagram / rostov.kraski.kisti)

Recommendations and safety precautions

Safety measures during work are strictly observed. Otherwise, unexpected difficulties may arise. Follow the following rules:

• When working inside a building, it is first ventilated;
• If paint or thinner is spilled, sand is poured onto the stain to prevent a fire from starting;
• The master must wear a protective mask and gloves;
• You cannot eat indoors while painting;
• It is prohibited to pour paint into sewer pipes.

Safety measures during work are strictly observed.

Metal painting can be done at home, the main thing is to choose the right paint. Also act step by step to get a high-quality result that will last a long time. The article described how to paint metal correctly; following the recommendations will help you cope with painting.

Types of metal that can be painted

In order to ensure a long service life, it is important to choose the right paint and varnish for a particular type of metal.

The most commonly used metal is black iron. Oil-based paint is applied to this material. Before applying paint, it is necessary to treat the surface with a zinc-based alkyd primer. This is done so that no rust spots can be seen from under the paint layer.

Non-ferrous metals are usually painted with varnish:

• Epoxy;
• Polyurethane.

The roof of a galvanized house, if covered with alkyd paint, will last twice as long. A poorly carried out surface cleaning procedure will lead to detachment of the coloring layer. In our company you can order painting of any metal. By choosing us, you get guaranteed quality results.

Types of metal painting

Metal can be painted in different ways:

• a paint brush for metal, which is suitable for processing products with a flat surface and small sizes,
• roller - for large-sized products with a flat surface,
• by dipping into paint, which works especially effectively with small parts of complex shapes,
• air and airless spraying from a special apparatus; this method is used if you need to paint large products of arbitrary shapes.

Separately, powder coating is distinguished - painting with powder with a polymer structure and subsequent polymerization of the coating, which makes the product resistant to temperature changes, mechanical damage, and rust. Powder dye is suitable for almost all types of mechanical surfaces, it is relatively easy to apply with a spray gun, and therefore is very popular in industry, the automotive industry, etc.