Homemade compressor for painting a car with a receiver. Which compressor for painting a car to choose. Correct performance calculation

14.07.2018

Painting a car is a responsible undertaking. The main task of the master is to choose the right compressor for applying the paint layer. It is from this unit that the quality, strength and consistency of the coating depends. If the choice of a compressor for painting a car is made incorrectly, then pressure fluctuations and poor quality of painting are possible.

Screw compressors

To help you, we have summarized in this guide what to look for when it comes to a boiler liter. Here you can find out what the compressor boiler should do, how many liters should be recommended, which compressor with a capacity of 50 liters and which compressor with 25 liters is recommended.

The operation of the compressed air cylinder in the compressor

Compressors with one boiler work on the same principle. The compressor compresses the air and pushes it into the boiler. The compressed air you have on your module comes directly from a previously filled compressed air tank, not directly from a compressor motor.

A compressor is a device that operates on the principle of a pump, but does not supply water, but compressed air or gas under pressure. Its main task is to prepare the air mixture for subsequent use.

There are professional, household and semi-professional models:

household designed for intermittent use with operating pressure up to 8 bar and continuous operation up to 20 min/hour. The volume of the receiver in such devices varies in the range of 6-100 liters.
semi-professional(semi-domestic). Duration of work - no more than 40 min / hour, pressure - up to 16 bar. Supplied with a receiver, volume 50-100l.
Professional(industrial) compressors are used in industries. Differ in a big resource and high efficiency. Receiver volume - 25-900 l. Suitable for long-term intensive work.

In addition, compressors are divided into mobile and stationary:

This principle allows the compressor not to work in continuous operation. Thus, the engine starts, fills the boiler with compressed air, and then goes into sleep mode. If the tank is under a certain pressure range, the compressor fills this compressed air bottle with air again and goes out again.

How many liters should the compressor boiler contain?

Compressors are available with different operating modes. How many liters and, if you like, should contain your kettle, depends on the service life and that. In general, there are three main areas of application that should be clarified before buying. If one knows this application range, one can determine the number of liters that the boiler should contain. For more complete information, you should use our.

Stationary installed on a special platform;
mobile equipped with wheels and a special handle for transportation.

Application

What kind of compressor to choose for painting a car so that it fully meets the parameters required for work? After all, he will allow you to perform not only high-quality finishing painting of the car, but also a number of other tasks or related procedures:

What you need to know when buying

Compressor for filling tires, balls, mattresses and Co. completely without a compressed air bottle. A compressor for compressed air work of all kinds, such as blowing, painting, sandblasting or airbrushing, must have a capacity of at least 20 liters.

Criteria for choosing compressor models for car painting

This means that with this compressor you can do all the work that you can do with a compressor at home and for professional purposes. Even though it's only 24 liters, you hardly notice the missing liter. This compressor has a maximum pressure of 8 bar and a power of 1.1 kW. It is thus compressed air work such as painting, painting and airbrushing can be done perfectly. This compressor is not suitable for compressed air.

Starting equipment that operates due to compressed air;
Application of primer, varnish or paint;
Blowing / blowing parts;
tire inflation;
Removal of any kind of contaminants from mechanical units;
Application of anti-corrosion agents in hidden and hard-to-reach car cavities;
Work with pneumatic wrenches, polishing or grinding pneumatic tools;
Other.

Characteristics

The choice of a compressor for painting a car will be simplified if you pay attention to the following technical characteristics:

For other compressors, we recommend that you check out ours. Because compressed air tools have many great features: they are light, efficient, quiet, easy to maintain and very durable. At first glance, they offer many benefits and are of particular interest to processors and air freight.

Compressors are very versatile in your application.
For this reason, buying advice is very important and extensive.
Because devices vary a lot depending on the application.

While some air compressors are so handy they almost fit in a glove box, others are so big they fill the entire trunk of a small car.

Weight and dimensions;
Receiver volume (l);
Productivity (l/min);
Compressed air pressure in the receiver (atm);
Engine: gasoline or electric
Power supply (220 V, 380 V or mixed - 220/380 V);
Power consumption (kW) of the power plant.

Performance

Before choosing a compressor for painting a car, you should first consider one of the most important factors- performance. It is measured by the amount of air compressed per minute (in liters). Note that when working with different spray guns, different volumes of air will be consumed.

In this buying advice, you will find out which applications are suitable for you, which different types of compressors are specially adapted for this application, which important indicators are important and which different operating modes are set. This information is needed to help you buy the right compressor.

Compressor use

Compressor ratings and comparisons

To compare devices with each other, let's give you short review compressor performance. From now on, you can start with all the metrics of a compressed air compressor to buy the right compressor for you.

Pressure

In the receivers, the maximum discharge pressure is approximately the same - 8-12 atmospheres. As soon as the air is compressed to 8 atmospheres, the compressor unit will automatically turn off. The threshold for turning on the unit is 6 atm. When this indicator is reached, the missing gas is replenished. The desired value can be set independently, it will be controlled using a pressure gauge. The thermostat will be very useful - option automatic shutdown in case of overload.

Suction Power: Suction power describes how much air a compressor pulls from air to compress and convert it into compressed air. This value is always greater than the much more important output, and not ideal as a performance index. Fill volume: Fill volume describes how much air is pumped from the engine into the compressed air reservoir. This ratio is very abstract and not ideal for comparison. Boiler Size: Compressor boiler size is a very important measure. It describes which filling volumes fit into the compressor container. The larger the compressor, the softer the device. Because the engine fills the container and doesn't start until the container is empty. Beyond what is expected, this value provides little information. Pay attention only to pumping work and tools with very high pressure. Type of connection: Compressors operate in three types of connections.

This is one of the key indicators of the compressor.
Allows you to determine if there is enough air on your future device.
This value is also declared in liters per minute.

In the mode of operation of the device are significantly different.

Power supply

It is worth remembering that with an increase in pressure of 1.0 bar, the compressor will consume 8% more electricity. After all, while compressed air is supplied to the consumer point, there is a significant pressure drop, both in the filters and in the dryer and pipelines. Accurate determination of the required power will help to reduce energy costs, and accordingly - right choice compressor.

As already described, there are devices with and without a boiler. Now there are units that have direct drive. The engine drives the compressor unit through the shaft, which now compresses the air. In contrast, the V-belt is much more durable and only found in expensive equipment. Most of these devices are equipped with separate air cooling.

The most important difference, however, is the oil pressure system. Cheap devices operate completely oil-free and thus do not distribute oil in the compressed air mixture. Especially when working with color is very important. Another type of compressor is constantly mixing. These devices are much stronger and work "rounder". However, these air compressors also distribute oil in the compressed air mixture. This makes it difficult to work with paint, here it is necessary to clamp the oil separator. It doesn't cost the world.

Volume

For painting a car, it is better to choose a receiver with a volume of at least 50 liters. Often, the increased volume of the receiver allows you to compensate for the insufficient performance of the device.

Kinds

In addition to the above, there are several types of compressors for painting cars, which are classified according to various criteria, for example:

For new or complete paint, we always recommend a two coat! However, if your vehicle single coat, you should also use a single coat of repair paint. Here's how you can test it: buff on a cotton wool polish or fine sandpaper, rub in a place that is not very noticeable, if so, this is a single layer finish, since the transparent layer has no color.

The base coat is ready to be sprayed, so please do not add any other materials. Depending on the viscosity, temperature and care when cleaning edges and corners with silicone remover, so-called edge run-out may occur during painting.

According to the lubrication system (oil-free and oil);
By type of drive (belt, coaxial);
By the number of compression stages (one-, two- or multi-stage);
By the nature of air compression (membrane, piston).

Oil free

One of the most popular are oil-free piston compressors. They are used for work when the oil content in the paint is not allowed more than 0.01 mg / m 3. Units allow to carry out high-quality painting and to reach an ideal look of the painted surface. To remove excess moisture from the compressed air flow, an adsorption dryer is used, which is characterized by a dew point of not more than -70⁰С. Compressors are very reliable and easy to operate, moreover, they do not require professional maintenance. But the list of their functions and service life is limited.

Features of oil-free reciprocating compressors

Usually the varnish is tightened along the edge and closes it. However, if silicone residue is on the edge, the paint over the silicone gives way to poor adhesion and loosens the edge. If a paint material too thin or too thickly splattered around the edge, clipping may occur.

This is especially frustrating because you have little to no way of compensating for this out-of-edge run - the next layer recedes, greatly increasing the risk of runners in the near-edge area. Since when you open the paint cans and stirring the smallest particles of dirt can get into the paint, then when painting in the middle of a new hood, you should always pour any paint through the paint filter or paint when it is filled into the gun.

Oily

More interesting will be an oil unit using a lubrication spray system. It is presented in several versions. A common distinguishing feature of such devices is the oil that is poured into the crankcase piston pump. Due to it, a film is formed during operation, which prevents direct metal-to-metal contact. Consequently, the degree of wear of parts and heat generation is reduced, but the high performance of the compressor is maintained. Since some of the lubricant can get into the compressed air, apply various filters and oil separators. The main drawback is that in frosty weather this device starts worse than oil-free, as the oil thickens in the cold.

Be it mirrors, interiors, bumpers, panties or something else: many plastic parts have suffered very well over the years and can no longer be mastered by all the tricks from the care shelf. Or rough plastic surfaces should become beautifully smooth and shiny.

Homemade compressor - an easy way to make

It really helps to draw and it's also a good start to get some practice. Important: plastic parts are more difficult to work than sheet metal and therefore need elastic paint, which otherwise just breaks. And of course here: the pre-work is extremely important, so use the right primer and the right filler and putty knife so that all the shine doesn't end up in the first car wash on the track.

Oil compressors for painting cars are equipped with a belt or direct drive type.

Direct drive (coaxial)

In this case, the motor shaft and the crank are combined through a coupling, forming a single unit. Their main advantage is compactness and simplicity of design, but such a scheme makes it difficult to remove heat.

Do not place parts on the floor

We will soon be launching a complete plastic range which includes a repair kit for broken parts etc. But at the same time, we can also help with materials from other manufacturers. The parts to be painted should be as far from the ground as possible, because when sprayed with compressed air, it kindles the dirt and dust that has been lying around since time immemorial. So your best bet is to use a professional paint shop, or get some bucks from the store and put the pieces on top of it.

Belt driven

They work on a standard belt drive system from a pulley and an electric motor. They are distinguished by reliable air cooling, high performance, reduced noise level and long service life due to reduced engine speed. Belt driven compressors, in turn, are divided into one-, two- and multi-stage.

Just don't: put on a plate, table or similar. Also go: tighten the ropes to which the smaller parts are attached. Annoying: They start commuting if you can't do stable construction from several ropes. This is an important topic in our painting instructions because it is the most important thing in automotive painting: pure preliminary work. By the way, many bodybuilders refuse to draw prepared cars for this very reason.

In any case, a clean, thorough preparation with high quality matched materials is just as important as after a base coat and a clear coat or a single coat of paint. Because a bad surface cannot be compensated for with a thin layer of base coat and a clear coat under any circumstances. You can see everything through it like a wet t-shirt.

Piston

These are the most popular models due to their simplicity and reliability. The principle of their operation is that the electric motor activates the piston through the crankshaft and connecting rod. Under pressure, the outlet and suction valves close or open. This type of compressor for painting cars can be equipped with one or more cylinders arranged in a V- or W-shape. To increase productivity in such units, two-stage compression technology is used.

Screw compressor for car painting

If you want to choose a new color for your car, the easiest way to do so is to simply walk or drive the car mile and look at current and used models. If you find a color there that fills in, you're almost always on signs and the same color name on it, and then you can fill in here in a color-coded color search.

Recommendations for the selection of compressors of any design

To avoid this, there is only one solution: touch it properly. It's better to get a big slide in the store and pick up the whole car properly, as after a few hours of polishing the entire spray mist from the roof, because you just wanted to enter only the bumper. Masking takes time, but saves a lot of work!

screw

Compression of air in these models is carried out due to the simultaneous rotation of the rotors, which are located in the housing parallel to each other. In this case, special cells are formed, the volume of which gradually decreases, creating increased pressure. The devices are equipped with monitoring, control and protection systems (ACS), which allows you to quickly and easily configure them to work in the desired mode, depending on the conditions. This will ensure an uninterrupted supply of compressed air for a long period of time. They are distinguished by low energy consumption, minimal vibration and noise levels, high quality of exhaust air, durability and reliability. They are used in large enterprises where continuous operation is required.

Membrane

Classified as a household tool and intended for occasional use. Distinctive feature– low productivity in steam with high pressure.

Have you made your choice?

The modern market offers a wide range of compressors, both foreign and

Applying paintwork

domestic manufacturers. But when deciding which compressor to choose for painting a car, it is important to remember that you should not save on it. Unit with good performance will pay off very quickly (perhaps after the first painting of the car or its individual elements). After all, often, even the cost of painting a bumper is comparable to the price of an average power compressor.

We offer you to watch a video that will help you make the final choice of a compressor for painting a car:

A paint compressor is a must-have for professional car painting. Functional purpose compressor - supplying compressed air to the spray gun, through which the paintwork material is sprayed onto the surface to be painted.
Quality paint for all types of work

This article provides an overview of compressors for painting - piston and screw units are considered, and recommendations are given that will help you choose the right compressor for pneumatic tools.

Screw compressors

The screw compressor for painting a car operates by rotating two rotors located parallel to each other. In the process of rotation of the rotors, their helical blades form cells filled with air, which, as the position of the screw changes, decrease and compress the air that has entered them, which leads to an increase in the pressure of the air flow at the outlet.

screw electric compressors have a typical layout scheme consisting of:

Filter on the inlet pipe, which purifies the air from dust and small mechanical particles;
A suction valve that prevents the release of compressed air through the inlet pipe when the power drive stops;
Screw block - the basic working unit of the unit, consisting of a rotor pair, equipped with a sensor temperature regime, which stops the operation of the device with increased heating of the air flow at the outlet;
Electric drive, pulley and belt drive - units that ensure the rotation of the rotor pair;
Air cooling system for working mechanisms;
Control elements - pressure switch, pressure gauge;

High-quality painting of your car, both in large and small boxes

The screw paint compressor is manufactured in a metal case coated with a protective paint that is resistant to oil and chemically aggressive substances. Such devices are characterized by high performance - supply pressure up to 15 atmospheres, volume - up to 600 l / min.

Among the advantages of screw units, we highlight:

Low oil consumption, in comparison with piston mechanisms, at the level of 2.5-3 mg / cubic meter. Due to the reduced oil consumption, the screw compressor for painting provides a supply of clean air - painting a car with its use can be carried out without the use of additional cleaning filters;
The minimum level of noise and vibration, compact dimensions - the use of the unit does not require the preliminary arrangement of a reinforced foundation platform;
Economical energy consumption - 30% lower than that of piston mechanisms;
Built-in air barrier, which allows the unit to be used 24/7;
Wear resistance and undemanding operation, the presence of a thermal protection sensor. Choosing a compressor for a car screw type will deprive you of the need for regular replacement of valves, pistons, rings and seals, which accompanies the operation of piston units.

The only drawback of this equipment is its high cost. Russian screw compressors(Bozhetsky plant, Penzakopressormash, Borets OJSC) are sold at a price of 200 thousand rubles. The best compressors for cars made in Italy (Fini) and Germany (Berg) - costs from 250 thousand.

Piston compressors

Piston compressor - a budget solution, inferior in terms of performance characteristics screw units. This mechanism consists of the following nodes:

The cylinder and the piston moving in it;
Inlet valve for air intake and exhaust valve;
Power drive (electric), crankshaft and connecting rod, which connects the engine to the piston.

Portable painting of your car

When the compressor is running, the piston moves in the cylinder - the compression chamber. When it is raised, the air is rarefied and when the resistance of the spring closing the valve becomes less than the pressure of the flow sucked through the inlet pipe, the cylinder is filled with air.

When the piston moves back, the air is compressed, which leads to an increase in its pressure. Overcoming the resistance of the exhaust spring, compressed air exits through the discharge valve and enters the exhaust pipe.

This principle of operation causes a key drawback of the unit, due to which the choice of a piston-type compressor for painting works undesirable - the supply of compressed air is not carried out by a uniform flow, but by pulses, in time with the movement of the piston.

This problem is especially typical for single-cylinder devices; it concerns units with two cylinders to a lesser extent. In two-cylinder mechanisms, the pistons work in antiphase - at the moment of forward movement of the first piston, the second one makes a return movement.

To equalize the supply pressure, piston compressors are equipped with a receiver - storage capacity for compressed air. The pressure flow is not supplied immediately to the spray gun, but to the receiver, where the pressure drop is compensated.

Piston units, depending on the method of connecting the drive to the piston, are classified into two types - with direct and belt drive. Direct drive devices are compact in size, but the air belt compressor is more reliable in operation and has greater maintainability.

The choice of a compressor for painting a piston-type car makes sense when limited budget. The cost of such equipment starts from 10 thousand rubles for units of Chinese and Russian production. Quality Italian Air piston compressor for two cylinders will cost you 20-25 thousand rubles.

How to choose a compressor for different types of work

Initially, we note that all types of units - piston and screw, are of two types - oil-free and requiring oil lubrication:

In oil units, rubbing parts (rotor shafts or a cylinder and a piston) are in contact through a layer of lubricant, which leads to a decrease in heating and noise. The amount of injected oil depends on the performance of the compressor, in units with a capacity of 1 kW per minute, about 1 liter is supplied to the working unit. The lubricant is subject to recirculation, it is carried through the filter system, passes through the cooling unit and is re-supplied;
In oil-free units, the working elements are covered with a layer polymer materials, due to which a decrease in the force of their friction is achieved. There are also water-filled devices, where the heat-removing function of the oil is performed by water.

Compressor selection must be taken seriously.

The difference between an oil and oil-free compressor in practice is performance. Due to poor cooling (due to the lack of heat removal) and accelerated wear of rubbing surfaces, the productivity of oil-free units, in comparison with oil ones, is significantly lower.

Choose air compressor oil-free type makes sense for non-professional coloring. This device will be enough for periodic work (2-3 hours a day) when painting parts or individual body elements, however, such units are not used in car services with a constant flow of customers.

When choosing whether to purchase an oil or oil-free compressor, keep in mind that oil units require regular replacement lubricants. Replacement interval - after 100 hours of operation after purchase and every 1000 hours thereafter (at least one replacement per year). You need to pour oil into a piston air compressor synthetic or mineral (we recommend VDL-46 from Texaco and D46 from Shell).

When purchasing, it is rational to select a compressor according to the parameters of the spray gun used for painting. In the instructions for the spray gun, the manufacturer indicates what pressure and supply volume the unit used should have.

If you have not yet purchased a sprayer, follow these recommendations:

We choose a compressor for a car for the purpose of periodic use.

For painting, in which the equipment is operated for several hours a day, we recommend using two-cylinder piston-type oil compressors with a nominal air supply of 140-250 l / min, a power of up to 32 kW and a supply pressure of 6-7 atmospheres. The required volume of the receiver is from 20 to 50 liters.

The choice of a compressor for a garage among piston mechanisms is dictated by their low cost and satisfactory productivity. Such equipment will cost you 15-20 thousand rubles, but keep in mind that the performance of the compressor for painting a car should provide a power reserve of 15-20% in relation to the spray gun.

Selection of equipment for professional use.

If the compressor is needed for painting cars in intensive use, which is typical for car dealerships with a large number of customers, the choice comes down to oil screw units. Here you need a device with a supply pressure of 10-12 MPa, a capacity of 250-600 l / min and a drive power of 3-5 kW. The volume of the receiver is from 50 liters.

Additionally, you will need an absorption filter to clean the incoming air from oil impurities and a dryer. The estimated cost of a set of equipment is 200-250 thousand rubles.

Compact and very handy compressors

When choosing equipment for purchase, pay attention to the following characteristics of a compressor for painting cars:

The principle of operation is piston or screw (the advantage of screw is the uniformity of the flow, long service life; piston - price);
The principle of lubrication is oil (performance, noiselessness), oil-free (compact dimensions);
Type of connection between the drive and the working unit - direct (small sizes), belt (large sizes - wear resistance, maintainability);
Type of power unit - electric (from the mains 220 or 330V) diesel, combined;
Air supply volume (with a margin of 15% of that required by the spray gun);
The volume of the receiver - from 20 liters;
Supply pressure - minimum level 7-8 MPa.

If there is a problem with the power supply at the job site, you need a compressor for painting a diesel-powered car. This is a self-contained equipment, independent of the source of power supply.

When choosing units on an electric drive, consider what voltage they operate from in the network. During the painting process, voltage drops of more than 20 W are unacceptable, they are fraught with a change in air supply pressure and, as a result, uneven paint application.

WATCH THE VIDEO INSTRUCTIONS

First, use a voltmeter to measure the voltage in the mains (3 measurements - in the morning, at lunchtime and in the evening) - if the voltage drops below 200 W, you will need to buy a stabilizer along with the compressors.