Adjusting the gun for painting a car. Self-adjustment of the spray gun

Garden equipment 14.09.2023

Garden equipment

Painting cars, furniture, appliances and many other elements involves creating a high-quality, uniform layer, without smudges or unevenness. A special pneumatic sprayer connected to a compressor of sufficient capacity can cope with such a task. However, to get a decent result, a regular connection will not be enough. In order for the spray gun to reveal its maximum potential, it must be properly configured, setting the optimal pressure and other indicators. Next, we will tell you in detail how to adjust the spray gun and carry out a test painting, fully preparing it for effective work.

Regulators and their purpose

To successfully calibrate any device, you should know which elements of its design are responsible for changing performance indicators. The effectiveness of setting up the tool configuration directly depends on a clear understanding of the purpose and operating principle of these elements. Fortunately, adjusting the spray gun is not very difficult and boils down to rotating 2-3 valves (depending on the model), which we will discuss later.

Torch size regulator
A screw element that changes the position of a rod with a cone-shaped tip, reminiscent of a thick awl. Regulates the air pressure going to the head of the instrument by moving the rod closer or further from the through hole. The further the tip is located from the nozzle, the stronger the air pressure enters the head, creating a larger torch. The approach of the rod, on the contrary, limits the flow, reducing its influence on the formation of the torch. The maximum size of the torch is an elongated oval, and the minimum size turns it into a point.

Material supply
The flow of paint from the tank to the nozzle is blocked by a special needle, whose cone-shaped tip fits tightly to the inner walls of the nozzle. When the trigger is fully pressed, the needle moves back slightly, allowing the material to fall on the head of the spray gun and break into millions of tiny droplets under the pressure of the air flow. The feed screw adjusts the distance the needle will retract. Minimum paint supply means that the gap between the cone and the walls of the nozzle is very small and is not capable of passing a large amount of mixture. The maximum adjustment value, on the contrary, indicates that the needle moves a long distance, completely opening the exit to the air head.

Air supply
Fundamental setting of the optimal value of the input pressure required for the correct operation of the tool. Despite its importance, not all models are equipped with a built-in screw, forcing owners to resort to using third-party gearboxes (pressure gauges with regulators). Fortunately, more and more modern spray guns have the ability to change the air supply, without the need to connect third-party devices. Unlike the settings of the torch or material supply, which can be adjusted based on your needs, the volume of supplied air must have a single value specified by the manufacturer in the technical documentation. Reducing or exceeding the optimal threshold will distort the shape of the torch, making it unsuitable for professional work.

Setting the inlet pressure

The level of air flow pressure has a direct impact on the shape of the torch, where its excess deforms the spot into a dumbbell-shaped figure eight, and its deficiency guarantees paint accumulation in the center, but with a coverage area reduced by 60%. The quality and uniformity of material spraying by the tool depends on the value of this parameter. Many beginners, not understanding how to set up the spray gun, begin painting immediately after connecting to the compressor, which often causes serious inconvenience to themselves. There are several ways to set the optimal air supply, applicable to different life situations.

The exact pressure required by your tool to operate properly can be found in the technical documentation. The number with the prefix “bar” or “atm” is often indicated on tool packaging, and sometimes even on the pistol body.

Setting with pressure gauge
The most accurate and recommended way to adjust the spray gun inlet pressure. Requires a digital or dial gauge connected between the hose and the gun handle. Some modern models are equipped with a built-in electronic pressure gauge and do not require connecting additional equipment. For most instruments, especially the budget class, it is worth acquiring this measuring device. Setting the air supply can be done quite simply by following the simple steps of the instructions below.

Turn counterclockwise all the way, the air and torch size adjustment screws, setting them to the maximum value. The flow of paint does not matter and should not be touched.
While observing the gauge gauge, press the trigger lever to open the valves and record the pressure reading on the gauge. If the obtained data is below the required values, unscrew the adjusting screw on the gearbox or gun (if it is built-in). At higher values, on the contrary, we tighten it.
When the air flow is adjusted, open the paint supply to maximum. All that remains is to carry out a test staining and you can begin full-fledged work.

Setting without a pressure gauge on the spray gun
A less accurate, but calculated way to set the optimal input pressure for device operation. If among spray guns, only 15% of models are equipped with a built-in or removable pressure gauge, then the presence of this important element in the compressor is mandatory in 100% of cases. It is based on the output pressure of the compressor receiver that you can determine how many atmospheres will be at the outlet of the air hose (or inlet to the spray gun).

Calculation of pressure reduction is based on the simplest formula “the pressure on the compressor pressure gauge, minus that lost in the hose and filter, is equal to the inlet pressure for the spray gun.” For example: the air pressure at the outlet of the compressor is 3 atmospheres and passes through a 15-meter air hose with a diameter of 9 mm and a water separator. As you can see in the table below, a hose of this size will reduce the pressure by 0.6 atmospheres, and the water separator by 0.3. We subtract this data from the initial pressure (3 atm) and determine the volume of air received by the spray gun (1.9 atm).

Clean air filters reduce an average of 0.3 - 0.5 atm. In clogged areas, the pressure drops much more strongly.
Setup process steps:

Set the torch size to maximum and open to full air supply (if provided on the device).
We calculate the approximate pressure reduction based on the available elements. 15 m of air hose (9 mm) and clean filter. The pressure will drop by about 1 atm and (for example) to connect the SATA JET 4000 B RP (2.0-2.2) spray gun, you will need to tighten the compressor valve to 3.0 - 3.2 atmospheres.
If the resulting estimated pressure distorts the shape of the torch, it can be slightly reduced or increased by carrying out several test sprays.

If the required pressure is unknown

Not everyone purchases a tool exclusively from an official supplier. Sometimes such a purchase is made in markets and unknown sites, where there is a high probability of running into frankly ugly fakes that lack the usual technical documentation. But even on such a spray gun, dedicated to its creator, you can set the optimal inlet pressure. You will have to tinker with it longer than with a pressure gauge, but you can really achieve an acceptable result (if the tool itself is working properly).

First, set the air supply, material supply and torch size to maximum.
Fill the tank with paint material of suitable viscosity.
We carry out second sprays on the test surface, periodically reducing the air supply until we obtain a print of the most even shape.

This setup method requires experience and a trained eye. It’s not for nothing that prof. circles, the process of forced adjustment of a Chinese spray gun is considered an entire art.

Torch size and material supply

Once the spray gun inlet pressure is set to the optimal value, you can move on to less significant, but still important, settings. The amount of material supplied and the size of the torch have a direct impact on the efficiency of painting: from the number of passes to the thickness of the applied layer. In most cases, these parameters are set to maximum, but in some situations they take on other values. To more clearly understand how to adjust the spray gun for specific tasks, it is recommended that you familiarize yourself with the features of these settings.

Adjusting the material feed, changes the amount of paint that will flow to the air head when the trigger is pulled. Increasing or decreasing the parameter will only affect the saturation of the torch and the thickness of the applied layer. Allows you to save LMC in situations where a fine spray is sufficient. The optimal ratio of paint supply to torch size is achieved by setting both of these settings to maximum.
In 95% of cases, spray gun owners set the material flow to maximum. This is due to increased operating efficiency and reduced wear of the nozzle and needle.

Torch size affects not only the spray area, but also the quality of the layer, as well as the overall operating efficiency. Basically, this parameter is set to maximum, which allows you to quickly cover large areas while making fewer passes. Due to the reduction in passes, the number of paint overlaps decreases and the overall uniformity of the layer increases. Reducing the size of the torch is recommended for local painting, when the surface to be treated is small and does not allow spraying paintwork over a large area.

By adjusting the size of the torch, adjust the paint supply to it. Otherwise, during application, serious smudges may form due to excess material.

Nozzle selection

Setting up the optimal operation of the spray gun is not based on regulators alone. An important part of this process is choosing the right nozzle capable of passing materials of a certain viscosity through it. The larger the diameter of the central hole of the nozzle, the thicker the mixture can be fed through it. If you want to figure out how to set up a spray gun for high-quality painting, it’s definitely worth paying attention to this detail.

You can determine what size nozzle is needed for spraying paint and varnish material from the information indicated on its container. Almost every more or less large manufacturer of paints and varnishes indicates the required nozzle diameter in millimeters with tenths (1.4, 1.5, 2.0, 3.0, etc.). Among the most common types of coating sprayed by a spray gun are:

“Metallic” and other base enamels – 1.4 mm
Primers -1.4 mm
Clear varnishes – 1.5 mm
Epoxy primers – 1.8 mm
Liquid putties – 2.5 mm

The size of the nozzle opening affects the spray volume and the thickness of the resulting layer. If the hole diameter is smaller than required, the coating material will flow with difficulty and the painting speed will drop significantly. When the nozzle, on the contrary, exceeds the required dimensions, the paint is supplied in copious quantities, forming smudges or forcing the pace of work to be accelerated (in such situations, you can get out of the situation by tightening up the supply of material).

The choice of nozzle may depend on the “style” of the master’s work. Some prefer to make a thin layer, while others like to specifically fill the part with the mixture. If you are just a beginner, it is best to use the medium nozzle sizes recommended by the paint manufacturer.

Test Spray

Having adjusted your spray gun and selected the optimal nozzle, do not rush to start painting the required object. To make sure the settings are correct, do a few test sprays on paper, cardboard, or other vertical surface that you don't mind getting dirty. It is necessary to carry out this procedure to assess the shape of the torch, the uniformity of application and distribution of the material over its area. The most important test is considered to be the form check, and we will look at it first.

Imprint shape The spray gun torch, ideally, is an elongated oval with slightly blurred edges. The width can vary between 200-400 mm. The paint transfer must be uniform over the entire spray area and form an even print, without depressions or bevels.

When spraying, the spray gun must be held at a certain distance: 10-15 cm for HVLP, a little further (15-20 cm) for LVLP, and as far as possible (20-25 cm) for conventional sprayers (HP). It takes no more than a second to open the paint supply.

If the torch of your spray gun has the above distortions, you should know that they are caused by unregulated air pressure, clogged or defective nozzle. The dumbbell-shaped figure eight indicates increased air supply, which is corrected by lowering the inlet pressure. Too much paint accumulation in the center can be reduced by tightening the appropriate adjustment screw. If one of the air cap holes is clogged or defective, the torch spot takes the shape of a banana, which can be eliminated by cleaning or replacing the element.

Paint distribution the area of the sprayed spot affects the uniformity of the layer and is checked quite simply. To do this, turn the air cap 90° (for horizontal spraying), and press the trigger for 2-3 seconds until smudges begin to appear. If the drops are evenly spaced and have the same length, then the dispersion of paint molecules is correct and does not require additional calibration. If smudges predominate in the center or on the sides, the air or material supply should be adjusted.

Spray quality is a subjective indicator of the effectiveness of a pneumatic spray gun and is determined based on the size of the droplets transferred to the object. The size of the mixture particles can vary, increasing from bottom to top. Increasing the inlet pressure increases paint dispersion and reduces the layer size, making it rough and “dry”. To ensure that the spray gun layer does not cause any complaints, use the optimal operating pressure.

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Let's find out how to set up the spray gun so that the layer of coating being laid is as even as possible. After all, it doesn’t matter how high-tech and expensive a sprayer you purchased, without the correct adjustment of the tool, the quality of the painting work will be unsatisfactory.

However, before setting up the spray gun, let’s try to understand what this device is.

It’s easy to set up and use the sprayer for its intended purpose.

Devices for applying coatings by spraying are presented in a wide range on the market. The difference between the presented modifications lies in both price and the principle of paint application.

The work of painting sprayers is carried out in two stages:

the paint breaks into tiny fragments;
a torch shape is formed.

In the photo - types of torch in accordance with the type of spray gun

All sprayers on the market can be divided into three main categories according to their operating parameters:

Conventional systems (CONV) – characterized by high pressure in the spray head up to 3 bar.
High volume, low pressure (HVLP) devices up to 0.7 bar.
Low volume and low pressure (LVLP) devices up to 1.2 bar.

Regardless of the design of the spray gun, a torch of compressed air and paint and varnish materials is formed in the spray head. Leaving the spray head, the mixture in the form of a torch is distributed over a certain distance, and when it hits the surface, it forms a paint coating.

For household use, it is advisable to use large-volume, low-pressure paint guns, since they are more versatile in terms of the paint used and their price is more affordable compared to the cost of devices of other designs.

Preparing the room for the test

Before setting up the spray gun correctly, you need to prepare optimal conditions for testing.

It is advisable to experiment with applying paint and varnish in a workshop or garage, having previously cleared the room of various things and objects within a radius of 2 meters. We will try the spraying parameters on a vertical plane, for example on a wall or on a garage door.

In order not to unnecessarily dirty the surfaces, you can attach some unnecessary material measuring 2 by 1 meter to the wall or to the gate with your own hands. It doesn’t matter whether it’s old paper or plastic film - everything will do, because we’re not experimenting with color, but with hiding power.

So, the conditions for test staining are ready, let's start making adjustments.

Spray gun device

A pneumatic paint sprayer (spray gun) is a technically simple device in which compressed air, when supplied from a nozzle, sprays paint materials. Let's consider the design features of the painting tool shown in this figure.

Paint gun diagram

Here we see a traditional paint gun consisting of the following structural elements:

paint tank;
spray body;
a spring that drives the needle;
adjustment bolt for needle adjustment;
fitting for attaching a pressure gauge and an air supply hose;
spring holding the valve;
kernel;
mixture feed lever;
a needle that limits the flow of the mixture;
nozzle;
nozzle casing (head);
connecting adapter;
fastening nut.

Modern spray gun models supply paintwork materials from the tank to the nozzle. The mixture is supplied by compressed air, which is pumped by a pump or compressor.

Most tools for setting parameters are equipped with adjusting screws. Some high-tech modifications are equipped with an electronic torch adjustment system.

Diagram of an electronically controlled paint gun

Depending on the characteristics of the shape, the nozzle can be narrow-jet or flat-jet. That is, by choosing a suitable nozzle, you can achieve paint spraying in a strip of a given width.

The paint filling cup (tank) of the spray gun is usually made of transparent plastic. These tanks allow you to see how paint is being used.

General rules for adjusting the spray gun

In principle, the settings for paint guns are similar, regardless of the modification used. Therefore, let's look at the general rules.

The photo shows the location of the adjusting screws

The adjusting bolts are located in the following order:

adjusting the air supply from below,
adjusting the supply of paint and varnish materials in the rear part of the gun handle;
Adjustment of the torch parameters is again located behind the handle or on the side.

Symptoms of problems and solutions

As a rule, it is difficult to make a mistake with the location of the controls, since the design of the pistols is standard.

But, just in case, read the instructions for the device you purchased.

First of all, everything set the regulators to minimum. As a result, when you press the mixture feed lever, you will practically not hear the hiss of escaping air, and a layer of paint will not appear on the test surface.
Next, unscrew the adjusting bolt on the air supply from the compressor by 2-3 turns, so that the arrow on the pressure gauge is located between 1 and 2 atmospheres. There is no need to set the maximum pressure from the very beginning, since we will adjust this parameter later in combination with other adjustments.
So, We gave the air pressure and when we press the mixture supply lever we hear a characteristic hissing. Now open the adjusting screw responsible for the paint supply by 1-2 turns, and immediately open the torch by one turn.
Trying to paint. We place the gun at a distance of 25-30 cm from the test surface and briefly press the lever to spray the paint.

In the photo - the result of a close position of the sprayer - “orange”

Important: By placing the spray gun closer than 20 cm, you will get an orange-colored coating texture. Placing the gun further than 30 cm from the surface will result in insufficient coverage. As a result, you will have to apply paintwork in a large number of layers, which will result in excess paint consumption.

If paint comes out of the nozzle but does not reach the test surface, add air pressure. If the air from the gun bends the film attached to the wall, but does not paint it, add paint.

If the problem is not solved, increase the torch. By following these tips, you can find the setting that will get the paint onto the test surface.

Now Let's start adjusting the shape of the trace of the applied paint.

Features of torch adjustment

An optimally tuned gun leaves paint in the shape of a vertical oval. Moreover, the shape of the oval should be the same in the upper and lower parts.

It may be that the oval is uneven and the lower part is elongated. There are two reasons for this phenomenon.

First of all, try to hold the gun perpendicular to the surface being painted. If you hold the spray gun level, but the oval is still narrowed downwards, in all likelihood you need to reduce the paint supply.

If you do not do this and start painting, there is a high probability that multiple smudges will appear, which will not be easy to remove from the painted surface.

By almost completely removing the torch, we get a dot-shaped coloring. Such an add-on is necessary if we apply paints and varnishes to pipes or process internal cavities on any complex parts. Having removed the torch before painting in the shape of a dot, you should not linger in one place for a long time, since, again, there is a high probability of smudges.

When working with such a torch add-on, we paint in two layers. The principle is as follows: draw a line. Then, we place the next line so that it falls halfway on the previous line. This method allows you to achieve good coverage with low paint consumption and no smudges.

Important: Often it is not possible to adjust the spray gun properly due to the incorrect consistency of the paintwork material. When diluting the paint, make it so liquid that it flows like water, but at the same time paints the walls of the jar or vessel in which mixing takes place.

Conclusion

As you can see, the instructions for setting up the spray gun do not seem particularly complicated. Having a technically sound tool, paint diluted to the required consistency, and a little patience, you will certainly achieve optimal quality paintwork (see also the article “Spray gun for painting a house”).

Correct setting of the spray gun is the key to excellent results. The spray gun provides an even coating of the surface, without streaks and marks that arise during painting with a brush. A spray gun is an indispensable thing for those who care about comfort in their apartment. There are rules for setting up this device.

To obtain the desired result when working with a spray gun, you must configure it correctly.

Spray gun design and adjustment tasks

Modern models of spray guns have a similar structure. Their main elements are:

paint tank;
lever;
paint supply regulator;
air supply regulator;
a nozzle on which holes are placed for breaking the paint;
mechanism for regulating the spray pattern;
material nozzle with diffuser and needle.

All modern models of spray guns are designed in such a way that, if necessary, you can easily adjust any parameters necessary for normal operation using three regulators.

The spray gun can be adjusted only after paint has been poured into the tank. To set up, you will need a surface on which to test the work. A section of wall with a sheet of Whatman paper attached to it is quite suitable.

The correct approach to setting up the spray gun determines the final result of the work. Fine tuning requires compliance with 4 basic conditions:

paint preparation;
installation of a torch of the required size;
setting the correct air pressure;
regulation of paint supply.

Compliance with all these conditions can guarantee excellent results. In addition, a surface painted with a properly adjusted spray gun looks smoother and dries faster, and the process itself is much easier and faster.

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Preparing paint for work

Before setting up the spray gun, you should pay attention to preparing the paint. First of all, you need to properly mix the coloring matter and activator. Craftsmen and those who already have considerable experience in painting with a spray gun can measure the number of components by eye. Usually, the coloring component is poured in first, then the activator is gradually added to it - and so on until the desired consistency.

For beginners, it is better to hold off on experiments and dilute the composition, clearly measuring the number of components. How to do this and the necessary proportions - usually all this is written on the packaging. For example, if the marking is 2x1, then you should take 1 part of the activator and 2 parts of the mixture.

A measuring stick is usually used to mix volumes. But if you don’t have one, you can get by with a measuring container. In this case, a graduation is applied to the container, with its help it will be easier to measure the required portions of the mixture and activator.

An important factor that determines the quality of the finished surface is the level of viscosity of the composition. If you take it into account, the work will go much faster, and the surface of the walls will acquire an attractive gloss. To achieve the required viscosity, you need to add a solvent. The volume of solvent is also indicated on the packaging. It is designated as follows: 2x1 + 10%. In this case, 2x1 is the ratio of the volumes of the mixture and the activator, and the volume of the solvent is 10% of the total volume of the mixture.

By paying due attention to paint preparation, you can be sure of a good result. But if you don’t have the relevant experience, you should refer to the instructions. Therefore, when choosing a mixture, you should pay attention not only to color and price. The packaging should contain detailed instructions on how to prepare the material for use.

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Torch size and paint supply adjustment

Adjusting the spray gun begins with setting the width of the torch. The optimal torch size directly depends on the surface area that needs to be painted.

Full surface painting requires maximum torch. This will ensure optimal speed and uniform application. When painting with different colors, when there are fairly narrow color transitions, the width of the torch must be reduced and checked on whatman paper. Please note that along with reducing the width of the torch, it is necessary to reduce the air supply.

Once the spray width and optimum pressure are set, the paint flow can be adjusted. The adjustment screw must be tightened completely, then released 2 turns. You shouldn’t install a high feed rate right away: this will only ruin the surface and waste paint.

This can also lead to contamination of the spray booth and an unsightly appearance of the surface. Therefore, to begin with, it is better to set a low feed rate, and then, if necessary, increase it during the painting process.

The paint supply adjustment mechanism operates as follows: the movement of the steel needle is limited by a screw. Therefore, it cannot completely open the hole through which the paint comes out.

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Pressure control

Adjusting the air pressure is a more difficult task. If this indicator is set correctly, the color uniformity will be maximum. The difficulty is that for each case this indicator is unique. The indicators in this case are:

spray gun model;
viscosity index;
type of paintwork material (paint and varnish material).

Setting the optimal pressure in the spray gun is done using a regulator that is built into the handle or can be removable. In the first case, the pressure changes when the trigger is pulled. If you do not do this, then when you press the trigger, the pressure in the spray gun will increase sharply and the paint will spray unevenly. If the regulator is removable, then it must be opened completely in the place where the receiver connects to the hose. Then you need to pull the trigger and set the desired value.

The pressure required for proper operation of the spray gun is usually indicated in the accompanying documentation. But if documents are lost or for some other reason the pressure indicator is unknown, it can be determined experimentally.

To do this, you need to pour paint into the tank and open the regulators. We regulate the pressure: this indicator can be assessed using a short (1 second) injection onto the surface. The resulting print must be carefully examined, assessing all splashes, the size and shape of the droplets.

If the print resembles a pear or crescent moon, then the head or nozzle is faulty or possibly dirty. Flowing drops are produced due to insufficient pressure, and a number eight indicates that the pressure is excessive. You need to adjust the pressure until you get a well-defined mark on the sheet without smudges or compactions. Test injections should be made approximately 20 cm apart.

traditional type (high pressure): it is recommended to set the value within 2.5-3.5 atm.;
low pressure spray guns: recommended value - from 1.5 to 2.5 atm.

In addition, it is worth considering that for every 6 m of hose it is recommended to add 0.5 atm.

The correct choice of pressure and the correct setting of the spray gun allow you to obtain high-quality coating.

We use a spray gun to paint a car">If you decide to renew the paint on a car body, then more than 50% of the successful outcome of the job depends on having a reliable spray gun for professional painting in your arsenal. As for the remaining 50%, your patience and conscientiousness are needed here, but we are sure that you will have these qualities in abundance - this is your car after all!

The spray gun is also suitable for local painting: for example, you can use it to paint bumpers, wheels, and calipers. But if the areas are very small or difficult to reach, then it is better to take a spray can. Today we want to talk about how to prepare a spray gun, prepare the car itself, and paint with a spray gun. It is also very important to know how to set up the spray gun; the preparation itself includes 4 points, 3 of which are settings. And so, we need:

Prepare;
Determine and set normal pressure;
Set the torch size correctly;
Correctly adjust the paint supply.

Parameters such as viscosity also affect performance. We will need a plastic container and a clean wooden stick for work. You can read the proportions and recommendations on the paint packaging, where the manufacturer indicates what ratio is required, what to add, etc. To be sure of preparing the correct mixture, use a ruler to measure how much paint you are pouring. Don’t forget about viscosity: you can check the viscosity using the “old-fashioned” method with glass, if the paint forms a neat drop of 2-4 cm, then the viscosity is normal.

Some car paints require an activator, which is important for the spray gun in addition to the solvent. For example, metallic car paints are usually marked as follows: 2x1 + 10%. This means that two parts of the paint itself require one part of the activator, 10% indicates the required amount of solvent from the total volume of paint and activator. Using a ruler, this is quite easy to determine. The viscosity of the paint is very important for the spray gun itself; try to match the viscosity to the capabilities of the unit.

Settings

Setting up the spray gun

Take a look at the design of the spray gun - perhaps you will understand how it should work correctly. Well, if not, then read on to learn how to make the adjustment.
Main parts of the spray gun:

Paint supply regulator;
Air supply regulator;
Torch regulator;
The handle itself;
A nozzle in which a stainless steel needle and a double pneumatic diffuser are installed.

So, we are holding a spray gun with three regulators in our hands. How to set it up correctly for painting a car? First, pour the already filtered paint into the tank, where the viscosity is normal. Now we find the surface on which we will test the spray gun. A sheet of paper, preferably thick, is best suited for this.

Car customization

Next, adjusting the spray gun for a car flows into adjusting the torch. The most important thing is to adjust the width of the torch, because it is what shapes the paint. If you are painting a small area of the car, then you need to set a small width - then the spraying will be more accurate. If the surface is large, then you need to set up a wide torch - then the work on painting the car will go much faster. Important: if you reduce the size of the torch, you should reduce the air supply.

The image will help you determine which regulator is configured incorrectly.

The real adjustment begins with pressure, because the paint supply depends on this parameter. It may vary depending on the viscosity. So, we set ourselves a test material and begin impromptu painting. We make a couple of emissions and evaluate the work:

If dense large spots remain and the paint sprays in drops, then you have set the level too low;
If the torch looks like a figure eight, then the pressure is also not set correctly - too high;
If the stain has a strange shape, resembling a banana or pear, then the spray gun, or rather its nozzle or nozzle, is clogged.

When the spray gun produces a rounded torch, it means you have configured all the parameters correctly. It is important that the spray gun delivers paint evenly, without smudges, sagging or large drops - these are also important factors that mean that it is configured correctly - you can paint the car. Based on these factors, you can determine the setting of the spray gun.

Painting

The preparation is completed, you can use the spray gun to start painting the car. If you managed to set up the spray gun correctly, painting will be quite simple: pull the trigger and start moving it over the car body. It is advisable to paint in 2-3 layers and then varnish the body, but you probably already know this. But in order for the work to be done efficiently, you need to follow the rules:

The spray gun must be moved strictly parallel to the surface of the car body, and the speed on it should not exceed 300-400 mm/s. If you move it too quickly, the coating will be uneven and too thin. Slow movement threatens oversaturation and leaks;
The distance from the nozzle to the caliper should not be more than 25-30 centimeters. It will be great if you maintain this distance throughout the entire painting of the car body and caliper. If you move the spray gun away, the adhesion of metal and paint will greatly deteriorate, and consumption, on the contrary, will increase. What happens if you bring the unit too close is already clear;
The shape of the torch should be oval, and the size should not exceed 30 cm;
Do not allow the spray gun to deviate too much in the vertical and horizontal planes. Obviously, you can’t calculate 5-10° by eye, but this is an acceptable angle of inclination;
The first layer is sprayed horizontally, and the second – vertically. Each subsequent strip overlaps the previous one by 3-6 centimeters - with this action, painting the surface of the car body will be maximum;
Do not move the spray gun away when you approach the edges of the area to be treated, as this will lead to unpleasant consequences in the future - the layer will begin to peel off from the edges.

Electric spray gun and homemade unit

If you already know how to properly prepare and set up a mechanical spray gun, then using an electric spray gun will be quite simple. The main thing is to study the instructions well, where it is requiredThe rate of pressure, torch and paint supply will be clearly indicated.

In general, using an electric spray gun is easy, but it is quite expensive. But making a homemade one will be problematic, because a homemade spray gun requires skills in working with regulators and pressure. And not everyone can boast of this, but there are drawings from which you can make a homemade spray gun.

Now we know not only how to properly paint a body with a spray gun, but also how to set up this device - and preparing the tool for work here is one of the most important stages. The design of the spray gun is now also known, all that remains is to purchase all the necessary elements and start painting the car.

Rules for using paint sprayers

When preparing a paint sprayer for work, first of all, check the spray heads, they must be clean, the holes of the material nozzle and the air cap must be coaxial. The end of the tip of the material nozzle should protrude somewhat from the air cap (for paint sprayers with an upper or lower paint pouring cup) or slightly recess into it (for paint sprayers with paint supplied under pressure). The axis of the side air holes must intersect the axis of the central hole of the head. When you press the trigger, the locking needle should move away quite freely and smoothly, and when it is released, it should tightly close the hole of the material nozzle. Oil seals, gaskets, seals of the air valve shut-off needle and head must be tightened sufficiently well to prevent paint from entering the air line or air from entering the paint line, as well as leakage of paint and varnish material during operation. When the trigger is pulled, the compressed air hole in the spray head must open before the material nozzle hole opens and paint begins to flow out. Otherwise, unsprayed drops of paint will inevitably be released when the spray gun is turned on and off.

Before starting work It is necessary to check that the spray gun is adjusted. To do this, perform a test application of paint and varnish material on a separate sheet.

After finishing work An appropriate solvent is passed through the paint sprayer and the hose through which the paint and varnish material is supplied for rinsing.

Washing is carried out until clean solvent appears from the spray gun. After washing the paint sprayer, its channels are blown with air, then the air cap removed from the body is washed in a solvent if its holes are clogged with paint. Thus, they are cleaned with a wooden pin or copper wire; it is prohibited to clean the holes with steel wire. During short breaks in work, especially when applying quick-drying paints and varnishes, it is advisable to place the head (item 2) of the paint sprayer in a tank (item 1) with a solvent (see figure), which protects the paintwork material from drying out in the nozzle, otherwise it is necessary to disassemble the spray gun. You need to lower the head into the tank so that the solvent does not get on the seals.

Rules for spray painting

The correct technique for performing spray painting work according to a few simple rules allows you to increase productivity, improve the quality of the coating, and minimize losses of paint and varnish material.

The main conditions for achieving coloring effects are:

1. Selecting the appropriate spray gun.
Depending on the size of the products to be painted, a spray gun of appropriate dimensions should be used. Small items and small surfaces should be painted with small-sized paint sprayers, as this will ensure economical consumption of paint and compressed air.
Large surfaces should be painted with large-sized sprayers that ensure high labor productivity.

2. Selecting appropriate nozzles for paint and air supply.
The type of nozzle for supplying paint depends on the type of paint and varnish material, as well as on its quantity, which must be applied to the surface (coating thickness) in accordance with technological requirements.
The type of air nozzle is determined by several factors, namely: the amount and pressure of compressed air, the dimensions of the products being painted, the type of paint and varnish material, the required painting speed and the method of applying paintwork materials.

3. Adjusting the spray gun, compressed air pressure and paint supply.
Before painting it is necessary to make adjustments:

pressure of paint and varnish material;
atomizing air pressure;
width of the jet of sprayed paint.

Spray guns are equipped with an adjustment nut to reduce or increase the flow of material. It is recommended to install the needle in a position that ensures full opening of the nozzle to supply paint, and regulate the shape of the torch with air pressure. To regulate the atomizing air pressure, some spray guns are equipped with a spray air pressure regulator, while others are equipped with a reducer mounted between the air duct and the spray gun.

Too high atomizing air pressure causes excessive paint mist and paint reflection from the surface being painted, and reduces the coating thickness in the center of the print. Too low pressure causes the formation of a rough, uneven coating - “shagreen”.

The speed of movement of the paint sprayer over the surface to be painted depends on the amount of paintwork material coming out of the nozzle. In order to prevent the occurrence of local thickening of the coating, it is necessary to think through the sequence of strokes (movements) of the paint sprayer and, with the smallest number of such strokes, achieve complete coverage of the surface without twice overlapping the paint spray at any point.
The result of such a work plan should be: fast, free movement of the sprayer and obtaining a coating of uniform thickness without streaks and drips.

4. Spray gun stroke consists in its movement parallel to the painting plane at a certain distance, the axis of the spray gun should remain at right angles to this plane, and the distance from it to the spray head should be 20-25 cm.
The spray gun should be moved evenly from left to right and back along the entire length of the stroke so that the previous stripes (prints) of paintwork overlap the previous ones by 50%.
The shorter the distance between the spray gun and the surface to be painted, the thicker the coating. In order to prevent the occurrence of streaks and drips, the movement of the sprayer must be accelerated. Too large a distance leads to the formation of a “dry” coating - a rough one, as well as the formation of too much diffuse paint mist (see fig.)

The relationship between the speed of movement of the sprayer and the distance from the surface to be painted is easy to feel and a moderately skilled painter learns it very quickly.
The hand spray gun should be positioned parallel to the surface of the product. Obvious errors, such as the movement of the sprayer in an arc and in a vertical plane, are presented in the figure.

To obtain a uniform coating thickness, the first layer of paint and varnish material is applied in vertical stripes, and the second in horizontal stripes.
- The first strip is applied from top to bottom along line 1-2 to the end of the surface to be painted or to a certain horizontal line 2-3, then to apply each subsequent strip, the hand with the spray gun is moved to the right. At this moment, by lowering the trigger, the supply of paint and air is stopped, the second strip (section 3-4) is applied from bottom to top, etc. To obtain a continuous coating, it is necessary that the edge of the subsequent strip overlaps the applied paint strip by 5-8 mm.

When painting, do not move the spray guns in a wave or loop manner. The spray gun must be held perpendicular to the surface to be painted. If you hold it at an angle, the width of the print of the ink torch increases, and the thickness of the coating will be uneven. With the spray gun in a perpendicular position, the coating has almost the same thickness. Moving the spray gun is done by moving the body and arm, not the hand
When painting protruding parts and corners of products, the spray gun must be operated without moving the torch beyond the contour of the product.

The speed of movement of the paint sprayer should be uniform and within the range of 14-18 m/min.
The distance from the spray gun to the surface to be painted should be 200-250 mm depending on the viscosity of the paint and varnish material, a smaller distance for higher viscosity and a larger distance for low viscosity.

If the distance to the paint sprayer is greater than necessary, then the amount of paint and varnish material that does not reach the surface to be painted increases, and, consequently, its losses due to fogging increase. If the spray gun is located close to the surface to be painted, drips and unevenly covered areas will appear.

Starting and stopping the spray gun

The trigger is used to start and stop the spray gun. when this hook is returned in the direction of the handle, the paint output increases and therefore, during painting work, at the beginning of each stroke it is necessary to press it all the way and release it immediately before the end of the stroke.

The correct move should be carried out in the following way: