Read the article carefully to find important equipment for airless painting. Hopefully, you will find the right way.
Important Tips for Spraying With an Airless Sprayer
How familiar are you with the airless spray paint method? And what devices or tools do you use during the repair work with your own hands? Today I will tell you about the features that airless spraying has and what an electric and manual spray gun is.
The principle of airless painting
Airless painting is the use of special equipment in the process of work, with the help of which the paint is applied to the treated surface not by pneumatic means, but by dispersing the flow of paint and varnish material. The crushing of the coloring liquid is carried out without the participation of compressed air, so the method of coloring is called an airless painting.
The essence of coloring:
- Spraying of paint and varnish materials occurs as a result of high hydraulic pressure.
- The working composition enters the elliptical nozzle of the paint sprayer and flies out of it at high speed.
- As a result of the hydrodynamic action of the air, the paint material particles slow down.
- On the surface to be treated, the paint layer is applied more evenly and economically than when using a pneumatic spray gun.
In simple words, airless painting of walls and other surfaces takes place using a pump that feeds the paint liquid through hoses, and on an elliptical nozzle, the working composition is crushed into the smallest particles.
At the outlet of the nozzle, high pressure and highly atomized flow are obtained, the droplets of which meet the air medium on the way, slow down and cover the surface gently and evenly.
Mainly airless painting is used on an industrial scale and for the processing of metal structures. With the help of sprayers, it is possible to apply epoxy, latex, alkyd compositions, textured and fire-resistant coatings, construction primers when processing metal, wood, concrete, and other surfaces.
Electric and manual spray guns
An electric paint sprayer can not always replace the use of a roller or brush, but it can become an effective assistant in the processes of painting with your own hands. It seems to me that no private house or dacha can do without the use of new technological methods that can significantly simplify the work with your own hands.
If you have already decided for sure that you want to try the pneumatic version of the painting, then it remains to choose which devices you will use. There is an electric spray gun, it works with a compressor that pumps air to supply the solution and manual-the air is pumped into it manually by a special pump.
Personally, I think that for high-quality design, it is better to use an electric tool, but for rare processes and in order to save money, you can buy a manual device.
What should be guided when choosing devices for applying paint with your own hands?
- Very often, a manual spray gun is made of plastic – this option will be quite cheap, but the quality and durability of the element are not even worth talking about. As everyone knows plastic is subject to the negative effects of solvent and also does not have good indicators of wear resistance and strength
- An electric spray gun must necessarily have a metal nozzle
- It is from the materials with which both the manual and the eclectic device were made that it depends on which paints can be painted with their own hands. If you plan to use only water-dispersion paints, then plastic options are quite possible to use
- Universal spray guns are much more practical and profitable in terms of painting surfaces with their own hands using various types of paint coatings. Although its cost is higher than its cheaper counterparts, it will last you long enough to recoup the purchase costs
If you have chosen an electric spray gun, then refuse to buy cheap Chinese options. They often do not do their job well, as they direct the airflow in the wrong direction. In addition, most often the device begins to etch and it is possible to reveal this only in the process of painting surfaces.
Most often, Chinese spray guns cost about $ 30-70, but high-quality products can cost about $ 100 or more.
Important! When choosing a nozzle, follow these rules: for alkyd paints or nitroemals, use a nozzle with a hole of 0.6 mm. Water-dispersion paints require a hole size of 0.8 mm.
Advantages of the modern method
The main advantage of airless painting is the possibility of applying a thick layer of coatings and the use of solvents in a smaller volume. There are no foreign particles and air in the paint stream, due to which it is possible to obtain a high-quality and uniform coloring of the surfaces.
Spraying paint under high pressure helps to reduce the cost of paint and varnish materials and reduces the labor intensity of work, which is especially important when painting large objects.
Airless spraying has important advantages:
- Mechanization of the painting process and increasing the speed of work.
- Obtaining a perfectly smooth coating with a soft application of the coloring composition.
- No need for powerful ventilation by reducing the use of solvents.
- Increase the productivity of painting works and the possibility of applying a thick layer of paint.
- Saving of coloring compositions due to the large area of the sprayed stream.
- Improving the sanitary and hygienic safety and environmental friendliness of the painting works performed.
When performing airless painting, a working composition of a certain viscosity should be used. The paint should not contain large pigmenting particles that can precipitate.
When working with airless paint sprayers, it is not rational to paint small products and small surfaces, since it is not possible to adjust the area and intensity of the paint flow (torch).
Features of the equipment
The main difference between an airless spray gun and a pneumatic spray gun is the absence of air particles in the paint stream, although the equipment has an external similarity. The paint sprayer can be mounted on a mobile stand for more convenient use. Components of the spray gun:
- housing with working handle;
- paint supply nozzle;
- elliptical airless nozzle;
- pump with a capacity of 200-500 atm.;
- high-pressure hoses.
Airless spraying involves the use of high-quality equipment. All sealing elements must be sealed to withstand high pressure. The spray gun must have a safety lock against accidental pressing of the trigger.
The handle of the device must have an anti-slip coating and a comfortable shape. To prevent foreign particles and dust from entering the working parts of the paint sprayer, the equipment is equipped with a special filter.
Inexpensive spray guns are produced with plastic housings. The service life of such devices can be questioned since plastic is not inert to chemical paint materials and does not have a high strength to mechanical damage.
When performing airless spraying, it is better to use devices with metal housings. If you need to move in a confined space, preference is given to compact airless paint sprayers.
Types of tanks
Each supplied compressed air gun is equipped with a tank in which the consumable material is filled. The tank is made of plastic, so as not to create an extra load on the painter’s hand, because he constantly holds this part in his hand.
Pay attention to the lid of the tank – it has a small hole that is easy to clean – it serves to prevent the formation of a vacuum in the tank. If a spray gun with a lower tank is used, then a similar hole is located somewhere in the body.
The classification of tanks is based on the location of the tank:
- The upper one: The standard for most is used when the material used is not thick. The paint inside is fed into a high-pressure pneumatic sprayer by gravity;
- The lower one: It is convenient in the case when the painter is used to wearing a lot of paint at once;
- With external supply from a single tank: In this case, there is a booster pump that pumps the varnish from a centralized tank.
In the case when the paint is supplied from the tank on the handle, the spray occurs due to natural discharge. If the paint is located in a centralized container, then you will have to use a paint gun together with a compressor.
Important preparation steps
Before painting the spray gun, you need to adjust and check the power of the dye flow on a sheet of paper, cardboard, or an inconspicuous area of the surface to be treated. If uniform flows remain after adjustment, you can start painting, but if the composition is applied unevenly, you should use a more viscous working composition or reduce the flow of the supplied paint.
- The paint is filtered before pouring into the bucket with a special mesh. Next, the cleaning takes place with a filter that is screwed to the supply hose, and with a filter located in the airless cleaning device itself.
- The drainage tube is placed in a bucket with dirty paint, and the supply hose is placed in a container with a working composition. The equipment controller is turned to the desired position and the airless device is switched on.
- When the paint comes through the drainpipe, it is lowered into the bucket. Connect the drainage and suction hose with a special clip, lower it into the container with the working composition. After 30 seconds of pump operation, the airless device is switched off.
- Painting of metal structures, walls, and facades begins with filling the hoses. Remove the nozzle, select the spray mode and wait for the composition to flow evenly. Put the gun on the safety catch and release the pressure in the device.
- The nozzle holder is installed in place, the nozzle is inserted and rotated so that the arrow on the part is directed forward. For different tasks (the viscosity of the composition), nozzles with different exit hole diameters are used.
- Turn on the equipment, adjust the pressure level and start painting. If the edges of the treated area are smooth, the machine is configured correctly. When painting, try to cover the previous layer by 50 percent.
There are two types of equipment: a gun connected by hoses to a tank for the working composition and a pump of the diaphragm, piston or pneumatic type, and a sprayer with a paint injection tank. These are two different types of airless paint spraying equipment – for industrial mass production and household needs.
Airless painting is a profitable and economical alternative to using pneumatic spray guns. With the help of special equipment, you can paint the facades of buildings, metal structures, supports, industrial, office, and residential premises, getting a high-quality and uniform coating.
The design of the unit consists of the following elements:
- Aluminum or plastic housing;
- Material supply hose;
- Electric drive;
- Safety system;
- Safety guard bracket;
- The rotary mechanism in some models.