What compressor capacity you need for painting
Perhaps the most correct classification of compressors, comes from the way the air is forced into the receiver. Beginning from the method of operation of the pumping device, you can draw conclusions about the effectiveness of the unit as a whole, and conclude on the advisability of its use in certain works. To understand how to choose a compressor for a paint sprayer, you should determine the scope of work as accurately as possible and set your requirements for the quality of the layer applied. Do you need a perfectly even film, like you paint a car, or is an even film with small imperfections at a better price? Understanding the principle of operation, the proposed types of devices, it is much easier to make the best choice of the device that suits your needs.
One of the first types of compressors widely used in manufacturing and household. The compression of the air in the air reservoir, occurs due to the reciprocating motion of the piston in the operating cylinder, of which there can be several. Devices of this type have the lowest capacity, and a high noise level, but can work in very dusty areas and pump the highest pressure (up to 40 atm).
advanced piston compressor version with reduced noise level and high reliability. As the name implies, they require sufficient oil in the system and this oil must be changed from time to time (not often). Similar devices have a more advanced design and are equipped with filters for degreasing the air and thermostats to determine the oil temperature. During the operation of such a machine, condensate accumulates in the receiver, which can be drained manually, through a special hole, or automatically, with a special device.
Oil compressors drive, can be direct and belt driven. In the home or small business, the most popular is the second type, as it has low power consumption, with similar technical characteristics. The belt on the drive is subject to wear and requires periodic replacement, but it puts less stress on the motor, prolonging its service life.
How to choose a compressor for a paint sprayer? What to use for painting with their own hands. Overview Video
The name of the mechanism in question is defined by the fact that it works on the basis of compressed air supply, which is mixed with the coloring substance. That is why such a device also has a compressor with a receiver. Choosing a compressor for a paint sprayer, you should pay attention to the following points:
- The paint sprayer itself is represented by a spray nozzle, which is made in the form of a gun. There is space for a paint reservoir on the top or bottom of the unit.
- The nozzle is connected to the atomizer with a special rubber hose. It has a fairly high strength, bendy, designed to supply air under a certain pressure from the generator to the actuator.
- The atomizer directly mixes air with the coloring substance, which is broken into small particles. This results in a quality coating.
- The shape of the mechanism is designed so that the air flow spreads in a torch, diverging at a certain angle in all directions.
Particular attention is paid to the fact that the devices must be made with quality materials.
How long they last depends on this point.
The atomizer is characterized by a rather complex design. It consists of the following elements:
- A conduit for the substance.
- Ducts designed for air supply.
- Air-type head.
- A reservoir for storing the colorant.
- The regulator, which allows you to change the parameters of the generated torch.
- A regulator that controls the direct paint flow.
- Air regulator.
- Nozzle for direct connection of the hose.
The relatively simple principle of operation means that the mechanism can last for a long time.
What is important to know about the compressor when choosing
Visually, almost all compressors seem to be the same, but looking at the cost of the equipment, you can see a large variation. The price is formed as a result of many elements and factors, and is also determined by the scope of use, purpose. Buyers should remember that it does not always make sense to take the most powerful and expensive device, especially if the work is planned periodic. Among the specific characteristics that affect the cost should be highlighted:
- Storage capacity (receiver). Many models are on the market from 5 liters, but there are also the largest 500 liters. The size can affect the activity of the device. The more compressed air is used, the larger the air tank must be. This provides the opportunity to reduce the load on the motor.
- Number of cylinders. Depending on the design and type of compressor installed 1-4 cylinders, the more of them, the sooner the air is pumped into the tank. 4 cylinders are often used in industry, while 1 or 2 cylinder models are sufficient for heavy loads and continuous operation.
- Motor power. All household variants are powered from the wall outlet, so no other connection is possible. The motor power is 0.5-3 kW, and the choice depends on the frequency of use of the device, as well as the degree of load.
- Working pressure. Based on the design and the specific model of the domestic apparatus, the value will be in the range of 2-12 bar. If the equipment is chosen for painting surfaces, the figure depends on the type of paint used. Liquid mixture requires a minimum pressure for quality spraying. For example, for water-based paints even 2 bar is enough, and under the hammer mixtures it is better to use from 8 bar.
- Mobility. This parameter will be important for a person who uses the technique in everyday life. Smaller compressors can be carried in the palm of your hand, but other units require stationary mounting. Mobility is provided by small wheels, which simplifies the transport of the device.
What compressor to choose for pneumatic tools?
When selecting a unit for your air grinder, plasma cutter, and other equipment, pay attention to the specifications:
- Air performance affects the maximum load. Before buying a compressor, decide what tools you will connect to it. 450-500 l/h is sufficient for most drills, impact wrenches, grinders, blowguns, etc.п. To keep the machine from running at full capacity, it must be 20-30% more powerful than other consumers.
- Output pressure is also selected according to the working parameters of the air tool. Household and semi-professional compressors typically have 6-8 bar. This is sufficient for almost all spray guns, wrenches, blowguns, etc.д. Industrial units have higher pressure, but require annual inspection.
- The air reservoir capacity affects the duration of uninterrupted compressed air supply. Air reservoir is a tank in which compressed air is pressurised and from where it is smoothly blown into the tool. The bigger the compressed air reservoir, the better: You can work longer without pumping and the air supply will be smooth. But a bigger compressed air reservoir takes more space and costs more.
How to choose a compressor for painting
Before you buy a device for painting cars, you need to determine the scope of its operation. It is possible to buy an air compressor for feeding the primer to the paint gun. There aren’t many requirements. But to create a beautiful and high-quality layer of paint, you need to comply with a complete list of conditions and characteristics. First and foremost, the equipment must be reliable. Only with this criterion in mind, you can choose a really durable and convenient tool for the car. Without observing this parameter, it will be extremely difficult to obtain the desired results.
How big a compressor do you need for spray painting?
Rotary screw and piston
Air compressors for spray guns can be piston and screw.
- Piston. They compress air through the movement of the piston in the cylinder. In the next phase of the duty cycle, a valve opens and the air enters the air tank.
- Rotary screw. Rotors are used here for compressing the air. They rotate continuously, sending air into the air collector or line.
oily and oil-free
Piston-type compressor units are of two types: oil- and oil-free. The first type is oil-powered, and the oil they use softens the work of the cylinder-piston group (CPG) parts. In the pumped air there are particles of oil, so it needs to be filtered (a device for cleaning and filtering the air is installed), so that oil does not enter the compressed air at spraying and do not spoil the painting.
Oil-free. uses piston rings made of Teflon. These units do not need any lubricant and are generally lighter in weight because they use aluminum components instead of cast iron ones. Teflon rings also need to be replaced from time to time.
Oil-free units do not require oil filtering of the air, but a moisture separator must be installed.
Oil systems are generally more powerful than prototypes and last considerably longer. Worth considering for applications where long-term operation is needed (small-scale production). They are perfect for painting: in contrast to the oil-free type, they don’t bubble up, ensuring perfectly homogeneous and beautiful coats.
Oil-less machines are well suited for mini-shops and garages: for pumping tires, connection of pneumatic tools, including those sensitive to the purity of the air. They can be easily maintained without the need for oil top up.
Directly driven and belt-driven
On direct-drive units, the motor pulley is directly coupled to the crankshaft. These compressors are considerably less expensive than V-belt drive machines. They are suitable for occasional, low-intensity use.
V-belt-driven compressors use a belt to transmit the motor power. They are more reliable and have a longer service life than units with a direct mechanism. Since the size of the cylinder block flywheel is larger than the size of the motor wheel, the number of crankshaft rotations is reduced, and the external mechanical resistance and wear of the mating parts is reduced. V-belt units have a much lower noise level, they are designed for longer operation, have better efficiency.
For professional activities, it is desirable to purchase a unit with a V-belt drive.
Connecting and operating the compressor when painting cars
We figured out what kind of compressor you need for painting. You can look for a variety of models and equipment options, paying attention to the characteristics and cost. The choice of equipment is not difficult, if you approach the selection of a comprehensive approach. Before painting works with the car, you need to set up the device and properly carry out all the tasks of its connection:
- Follow the quality of connection, use the preparation of the electric current;
- Do not use a compressor in polluted areas, always use air filters;
- Maintain your equipment, don’t forget to change and add oil periodically;
- Do not allow the device to operate with malfunctions, otherwise there may be trouble;
- Always check the operation of the sensors and other equipment, this will ensure the safety of the equipment.
When painting cars, you need to follow the factory’s restrictions and recommendations. Otherwise, you will have to deal with poor quality and unstable operation of the equipment. If the compressor equipment does not work within the declared parameters, it will not help you to create a good coat of paint. So make sure of the high reliability and good quality of service of the unit by reading reviews and look at the factory description.
One compressor is not enough for painting work. You will also need a hose, which is not included in the package, and the spray gun itself. For a budget level compressor, you can use a twisted hose, which includes and connecting fittings. Inexpensive Italian/Chinese-made devices can be used as a spray gun. You can also buy ready-made kits that include both a spray gun and connecting hoses with fittings, as well as additional tools (such as a blow gun designed for application of viscous paint compositions, or a gun for inflating the tires). With increasing demands on the quality of painting work, you need to be prepared that more expensive equipment will be needed.
Compressor consumables are filters and hoses. A straight hose is preferable to a spiral hose because the behavior of the latter is often unpredictable, and they can get on the surface to be painted. Without timely replacement of filters dust and other contaminants will get into paintwork without any obstacles and significantly worsen its quality (especially in case of metallized paints).
How to choose a good air compressor
Household air compressors differ in design, capacity, output, air volume and other characteristics.
Oil-injected compressors require oil in the crankcase, which is involved in the air injection process. They are efficient, durable, and can work for long periods without interruption. Of disadvantages: they need periodic replacement and topping up the lubricant, the pumped air contains oil particles, so it is not suitable everywhere.
An oil-free piston compressor requires no lubrication and is therefore easier and less expensive to maintain. These units are more compact than oil-injected units and provide the consumer with clean air without impurities. Not everything is the same with cooling, durability, and reliability. In spite of using low-friction Teflon, the mechanics wear out faster than in oil-based models. Their operating time rarely exceeds 15-20 minutes per hour.
An oil compressor is usually more powerful and lasts much longer. Suitable for applications where continuous operation is needed (small production). It is good for painting: unlike oil-free compressors, it doesn’t bubble up, making sure the paint is applied evenly and with good-looking coats.
The oil-free unit is ideal for garage and workshop: for airing tires, connecting pneumatic tools and those sensitive to gas purity. Easy to service. does not require oil refilling.
Available in bar or atm. the pressure units are identical. The rating is important for pneumatic tools and a variety of nozzles and must exceed the values listed on them. The data below is given as a guideline, when you purchase a compressor for work with some tools ask about the necessary pressure for its functioning and add 1-2 atmospheres for the future.
|Tire inflation gun||4|
|Tire inflator and rivet gun||6-7|
|Tool||Air flow rate, l/min|
|Nail gun and rivet gun||150-400|
Receiver is a metal bottle in which the air is pumped. The volume of the air reservoir affects the duration of work between pumpings and the time it takes to prepare the device for work. filling the air reservoir from scratch.
tool productivity. Performance of an air compressor is the volume of air it can pump in 60 seconds. Specified for work in normal conditions, choose a device based on the desired maximum plus 30-50% in reserve.
|Tools||Receiver volume, l|
|Blowing gun||From 250|
|Impact wrench||From 400|
|Nail gun and rivet gun||100-350|
What compressor to choose for air tools?
Before you buy, decide on the tools you want to use. Their total flow rate must be lower than the unit’s capacity by
25%, otherwise it will work close to its limits and will fail quickly. You don’t need a 50-80% stockpile, either. For household and most professional tools (nuts, screwdrivers, drills) pressure of 6-8 bar is enough, which means that the unit must pump 8-10 bar. The volume of the air tank depends on personal preferences and specific cases. With a large tank, the motor starts up less often and runs longer, pressurizing for a long time before use.
How to choose a compressor for car painting?
For airbrush and sprayer you need an oil-free compressor, while the oil compressor requires filters and oil traps. The rest of the parameters depend on the characteristics of the airbrush, and you must add 20-30% to them. With the painting works will cope household unit with a pressure up to 5-6 bar.