Every other time the electric spray gun works. Adjusting and checking the spray gun. Preparing paint for work

For uniform spraying of various paints and varnishes, primers, liquid putties, protective compounds and impregnations, painting devices called spray guns are used. This equipment may differ from each other not only in design, but also in its operating principle, which affects the quality of the applied coating.

Most often, both in household and professional field, electric and pneumatic paint sprayers with different tank locations are used. Also, these devices may have a pressure gauge built into the handle or connected to it.

An electric spray gun consists of a plastic or aluminum case, which contains the following elements (see figure below).

Electromagnet. Works in pulse mode, attracting the bar.
oscillating bar. It is attracted by a magnet and pushes the piston forward.
Paint regulator. Limits the mobility of the oscillating bar.
Nozzle. Sprays paintwork materials or other compounds.
Cylinder. It is the pump body in which the piston moves.
Valve. Opens and closes the paint supply.
suction tube. Designed for suction of paintwork materials. A filter may be installed at the end of the tube.
piston spring. After the piston moves forward, it returns it (together with the bar) to its original position.
Piston. Sucks in and pushes paintwork materials out of the paint sprayer.

The device also has a power button and a fitting for connecting the tank.

Spray gun worksaccording to the following principle. After pressing the start button, current is supplied to the electromagnet (1) in short pulses. At the same time, the electromagnet either attracts the bar (2) or releases it. The range of movement of the bar, and therefore the piston, is adjusted by screw (3). The bar, pressing on the piston rod (9), sets it in motion. The reciprocating movements of the piston suck the paintwork material from the tank and push the composition towards the valve (6). When the piston moves forward, the valve opens and allows paint to flow to the nozzle (4), through which it is sprayed. When the piston moves back, which is ensured by the expanding spring (8), the valve closes and the paintwork material is sucked out of the tank through the tube (7). Further, the process is repeated.

Important! Electric spray guns also include models with a remote compressor. In this case, the design of the spray gun is slightly different, and the principle of operation of the paint gun is similar to the operation of a pneumatic paint sprayer.

The tool runs on compressed air supplied by a compressor. Below is a diagram (sectional view) in which you can see the design of the device.

The pneumatic spray gun has the following elements in its design (see diagram above).

Spray head together with the nozzle (nozzle). The nozzle in the spray gun and the air cap are removable elements. They can have different outlet diameters, which are selected in accordance with the viscosity of the composition intended for spraying.
Paint tank. It is made of either plastic or metal, and can be installed either on the top or bottom of the tool.
Spray gun body. Serves as the basis in which all elements of the device are installed.
Locking screw. Regulates the intensity of paint supply by limiting or increasing the mobility of the locking needle. Some models of paint sprayers have an air supply regulator.
Lever. Designed to comfortably hold the tool in your hand.
Pad. Acts as a seal in the mechanism that moves the needle.
Trigger. Moves the locking needle.
Locking needle. Opens or closes the nozzle opening.

The operation of a pneumatic spray gun is as follows. When you lightly press the trigger, the air valve opens and air begins to flow through a separate channel into the air cap. As you press the lever further, the needle moves back, revealing a nozzle through which paint begins to flow. The paint, mixing with the air flow in the air cap, is crushed into small particles, forming an aerosol plume.

For comfortable work with a paint sprayer use a special wall holder.

Also widely used by painters spray gun stand, which you can easily do with your own hands.

Design nuances of paint sprayers with different types of tank

Spray gun device with top tank, as well as the principle of its operation, were discussed above. The only thing worth clarifying is the method of feeding paintwork into the tool body. Since the paint tank is located at the top of the device, it flows to the shut-off needle naturally, due to the force of attraction.

Spray gun device with bottom tank differs only in the location of the latter. Paint is drawn from it due to the vacuum created by the air flow inside the device. In the future, the operation of the paint sprayer does not differ from the operation of a device with an upper container.

In addition, not so long ago, equipment for applying paints and varnishes appeared on the market vacuum tanks. They are successfully used instead of standard paint spray tanks. The vacuum tank is a hard glass flask with a hole at the bottom into which a soft glass with a lid is inserted. There is a scale on the flask, which is convenient for determining the amount of paint.

The advantage of vacuum tanks is that they allow the spray gun to work in any position. Regardless of how the device is turned, upside down or upside down, the dye still flows into the gun thanks to the vacuum formed in the soft glass. In this case, the glass is deformed and the paint is completely squeezed out of it.

Setting the spray gun parameters before work

If you look at the body of a modern paint sprayer, you can see 2 or 3 adjustment screws. The first regulator can be located either on top or on the side of the body, as, for example, on SATA paint sprayers (see figure below). He is responsible for the shape and size of the aerosol torch.

The second screw allows you to adjust the range of movement of the needle, which determines the amount of paint and varnish supplied to the nozzle. Some models of paint sprayers have a third regulator. With it, you can control the air supply to the instrument.

Setting up the spray gun means correct installation material-air balance. By adjusting the optimal ratio, you can achieve the ideal shape of the aerosol torch, which will promote uniform spraying of the composition onto the surface being treated.

Gun inlet pressure setting

Important! The inlet pressure parameter is indicated by the manufacturer in those. documentation for the device and is standardized.

Setting the inlet pressure, ideally, should be done using a regulator with a built-in pressure gauge, which is connected to the handle of the device. This is explained by the fact that pressure losses in the line can reach 1 bar or more. The longer the duct and the more bends there are, the greater the pressure loss. Also, this parameter is affected by the installed filters and moisture-oil separators.

With regulator and pressure gauge

Adjusting a spray gun with an upper tank with an installed regulator and pressure gauge is not difficult:

First, you should unscrew the adjusting screw (1) as much as possible (see figure below), which is responsible for the air supply;

next, unscrew the regulator of the shape and size of the torch (2);
after unscrewing the screws, press the trigger (3), after which the air supply will begin;
on last stage you need to set the value on the pressure gauge (4) corresponding to the recommended one by turning the pressure regulator.

With electronic pressure gauge

Some “advanced” models of paint sprayers have a built-in electronic pressure gauge.

Adjusting a spray gun with a built-in electronic pressure gauge is even easier (see figure below).

Open the torch regulator as much as possible.
Pull the trigger.
Based on the pressure gauge readings, turn the air regulator until the pressure level at the inlet to the device reaches the recommended values.

With pressure gauge without regulator

If there is a pressure gauge without a regulator on the handle of the spray gun, you can correctly configure the spray gun as follows (see figure below).

Without pressure gauge

If the spray gun is not equipped with a pressure gauge, then you can make a rough, approximate adjustment of the device using a compressor gearbox, taking into account pressure losses in the line.

Advice! Before setting up the tool, you should take into account that the filter, if it is working properly and not clogged, reduces the pressure by 0.3-0.5 atm, not to mention a clogged element. In addition, approximately 0.6 atm. will be “lost” in the air hose if it has an internal diameter of 9 mm and a length of 10 m.

You can set up the spray gun for painting, if it does not have a measuring device, using the following method (see figure below).

If the spray gun is from an unknown manufacturer

Sometimes situations arise when there are no instructions for the device, or it is impossible to determine its manufacturer in order to find out what pressure is needed for the spray gun. The input pressure required for such an unknown tool can only be determined experimentally.

First of all, you should choose Standard viscosity paints and pour it into the tank.
Next, you need to unscrew all the regulators on the instrument and use the adjustment screw on the pressure gauge to “experiment” with the pressure. It is required to achieve a value at which a uniform torch imprint appears on the surface to be painted. In this case, the tool should be kept at a distance of 15 cm from the surface prepared for the test.
When the required result is achieved, record the value of the inlet pressure. This will be the operating pressure for this device.

Important! You should know that most cheap spray guns of unknown origin require increased air flow, more than 200 liters min., for normal operation. Accordingly, not every compressor will be able to provide such a tool. necessary quantity compressed air, which will affect the staining result.

Spray torch size

It is no secret that the effectiveness of coating using a paint sprayer largely depends on the condition of the torch. The larger its size and the higher the density of the aerosol, the more uniformly the coating is applied to the surface with a small number of passes. But in some cases it is required to install small size torch, for example, if you need to coat small parts or paint in hard-to-reach places.

Torch size is easily adjustable: by turning the screw towards the “+” sign, the spray width increases, and, conversely, when the regulator moves towards the “-” sign, the spray area decreases.

Advice! In most cases, this adjustment screw should be in the maximum open position.

Paint supply

When carrying out standard repairs, applying various coatings and painting bodies, it is recommended to open the material supply regulator completely. Usually this 3-4 turns of the adjusting screw. In this case, the nozzle should come off completely after pressing the trigger.

An important role when setting up a paint sprayer is played by the diameter of the nozzle. It is selected according to the density of the composition that will be used for spraying. Below is a table that will help you quickly determine what nozzle diameter you will need to apply different coatings.

Main malfunctions of the spray gun

Despite its simple design, the spray gun is still susceptible to breakdowns. Frequent malfunctions of the spray gun can be counted on one hand.

The gun doesn't paint

This happens in the following situations.

The air pressure in the system is extremely low. To correct the problem, the compressor must be adjusted.
The paint supply is interrupted due to the needle and nozzle being clogged. It is necessary to disassemble the spray gun and clean the listed elements.
The needle or nozzle is damaged. Parts need to be replaced.

Spray gun spits

The reason that the spray gun spits can be due to several malfunctions.

The air cap is not tightened properly. The part needs to be screwed on well.
The viscosity of the paint does not match the air pressure. It is necessary to achieve an acceptable pressure-viscosity ratio.
The paint is too thick. It is necessary to prepare a paint of less density.
The breather on the dye bottle is clogged. It is necessary to remove the plug and clean the hole in it.
The pressure in the receiver has dropped below normal. It is necessary to set a lower pressure threshold in the compressor settings that corresponds to the operating characteristics of the spray gun.

The torch moves to the side

If the torch of sprayed paint moves away from the gun, then the reasons for this may be the following.

Clogged side holes of the air cap. You need to remove the head and clean it.
Damage to the side air cap holes. The damaged part should be replaced.

Asymmetry of the torch spot

In this case, the problem may be caused by the following faults.

Nozzle clogged. Repairing the spray gun in this case involves removing the nozzle and cleaning its hole.
Nozzle damage. A part needs to be replaced.
The air cap is clogged, namely its central hole. The air cap should be removed, washed and cleaned.
Damage to the center hole of the air cap. This part requires replacement.

Painting is one of the most difficult types of bodywork. repair work. It takes a lot of patience and effort to make a paint job truly durable and attractive. You can’t do without special tools. If a car is painted without following the technology, after some time defects may appear on the surface. Next, we will talk about exactly what problems arise when painting with a spray gun and how to successfully solve them.

Problem #1: boiling varnish or paint

An example of boiling varnish or paint. Click on photo to enlarge.

The reason for the appearance of bubbles in the thickness of the paint may be the following mistakes made during painting:

incorrect setting of the spray gun, as a result of which it feeds excessively a large number of paints;
improper dilution of paint, resulting in it being too viscous;
slow movements with the sprayer, as a result of which a too thick layer of paint is formed on the surface, or too much overlap of the previous layer with the next one.

To eliminate such defects, the pigment is completely dried, then sanded and another layer is applied - the finishing layer.

Problem #2: cloudy paintwork

The main reason for a cloudy surface is moisture getting into the paint during its application. How and why does this happen?

painting is carried out in a room with low temperature, high humidity or wrong organized system ventilation causing drafts;
a low-quality or incorrectly selected solvent is used. If the room is cold and damp, you should use special remedy, and in minimum quantity, otherwise the paint will take a very long time to dry;
An improperly adjusted spray gun blows too much air when painting, causing the solvent to evaporate too quickly, cooling the painted surface and causing condensation to form on it.

The elimination of paint defects associated with clouding of the coating requires an elevated temperature in the workshop and the organization of proper air circulation. You should wait for the pigment to dry completely, then spray a special solvent on the defective area. For achievement maximum effect the surface is polished.

Problem No. 3: the appearance of craters

Craters - small funnel-shaped depressions in the paintwork - form for several reasons:

the surface is not properly prepared for painting, in particular, it is washed soap solution or liquid detergent, resulting in traces of silicone remaining on it. They are subject to mandatory removal;
during the preparatory work the surface came into contact with dust, fluffy rags, polishing paste and was not properly cleaned;
Oil got into the spray gun air duct.

There is only one way to deal with craters: sand the surface and apply a new coat of paint.

Problem #4: Cracks in the paintwork on sharp edges

Immediately after painting or after some time, defects in the form of small gaps and cracks may appear on sharp bends of parts. The reason may be one of the following shortcomings during painting:

applying paint in several layers without intermediate drying, as a result of which solvent accumulates in the thickness of the paint. This is what causes cracking;
use of poorly mixed paint and incorrectly selected solvent. If the paint is not well mixed before application, the pigment will be distributed unevenly and the coating structure will become spongy. If you made a mistake in choosing a solvent and chose a composition that is too fast-acting, you may encounter significant difficulties: the paint will adhere very poorly;
poor surface cleaning before local painting, as a result of which the primer, and with it the paint, will “slide” from the bends of the part due to low adhesion;
blowing the primer layer with compressed air immediately after its application, promoting rapid drying of the coating, but preventing complete evaporation of the solvent and the release of excess air.

Such defects are eliminated by removing the top layer of paint and applying a new one.

Problem No. 5: “shagreen” or “orange peel” on the body of your car

Shagreen on the body of a car. Click on photo to enlarge.

The appearance of this defect can be caused by various reasons:

incorrect setting of the spray gun or non-compliance with the painting technology (unregulated pressure, weak paint supply or too large a distance between the nozzle and the surface, etc.);
too much heat in a repair shop. Such conditions require the use of special slow-evaporating solvents;
insufficiently thorough mixing of the painting composition and its non-compliance with viscosity standards;
too thin layer of paint;
painting in several layers without intermediate drying or drying with compressed air.

In this case, paint defects are eliminated by sanding with abrasive sandpaper (the grain size depends on the degree of damage to the coating) followed by polishing. In the most severe cases, it may be necessary to reapply the final coat of paint after sanding.

Problem #6: varnish or paint smudges

An example of paint smudges. Click on photo to enlarge.

Smudges are one of the most common defects when painting, especially if it is carried out by a non-professional. They occur if:

paint is applied too thickly or without drying each layer before forming the next;
the air supply from the spray gun was carried out under excessively high pressure;
paint supply speed exceeded;
The gun nozzle is too close to the surface.

In most cases, it is possible to get rid of smudges by grinding and polishing, but sometimes repainting the surface is required.

Problem #7: dusty deposits

If the painting technology is violated, dry and semi-dry drops of paint may stick to a freshly painted surface. The main reason for the appearance of such a defect is the use of a quickly evaporating solvent in warm and dry air conditions in the workshop, as a result of which the paint dries very quickly. In addition, the reason for the sprayer supplying semi-dry paint may be its incorrect settings or a violation of the technology, namely overspraying onto adjacent areas that are not to be painted.

If a defect has formed on the varnish, it can be easily removed by sanding. Plaque on synthetic enamel is much more difficult to sand off, so it is recommended to sand the surface “wet” and then apply a new coat of paint.

Problem #8: Porous surface

Pores - small holes in the paintwork - appear for several reasons:

the spray gun is incorrectly configured or used incorrectly (insufficiently intense spraying or painting at too close a distance from the surface);
the presence of drafts in the workshop: air gets inside the paint and speeds up its drying, while all the solvent does not have time to evaporate;
varnish or paint is applied to a layer formed using “dry” spray technology;
when fed from a gun, the paint becomes contaminated with oil or becomes moist;
insufficient drying of intermediate layers, especially when working with “heavy” coatings;
incorrect technique for working with a putty knife;
incorrect choice of area for puttying or painting.

Troubleshooting

If the damage to the surface by pores is minor, it can be removed using fine-grained sandpaper. More severe cases may require wet sanding and reapplication of a final coat of paint or varnish. It will be possible to get rid of too noticeable pores only after sanding to metal and re-painting.

If we are talking about a layer of putty with pores, then it should be covered with another layer, while the putty knife is directed strictly perpendicular to the surface to ensure maximum filling of the pores with putty.

In order to prevent the appearance of pores on the paintwork, it is recommended to keep under strict control the temperature in the workshop, the viscosity of the paint, the type of solvent - in short, everything that affects the drying speed of the paint.

Problem number 9: garbage and dirt

Foreign particles on the paintwork appear due to:

using an unstrained working mixture of paint and solvent;
the presence of grinding dust on the surface to be painted;
settling of dust and other particles;
low quality filters,
insufficient cleaning of the gun before painting.

Elimination of this defect is carried out by stripping the coating to an undamaged layer and then applying the finishing layers of paint again. Cleaning is not carried out only if the foreign particles on the paintwork are frozen drops of paint sprayed from a gun.

Problem #10:

An example of a sharp color transition. Click on photo to enlarge.

This difference is especially noticeable when painting damaged areas locally. A clear border of colors or color distortion is a consequence of such defects as:

poor mixing of paint;
applying paint in a layer that is too thin so that the primer shows through;
violation of metallic effect painting technology;
interaction of old and new layers of paint.

In order to smooth out the color transition, the surface is treated with fine-grained sandpaper and then covered with another layer of paint.

Torch imprint issues

The top and bottom of the torch are spraying too much paint. This means that the paint or air nozzle is clogged or damaged. After repeated testing with the torch rotated 180°, the nozzles are cleaned and, if necessary, replaced with new ones.

A stream of paint forms a curved spot on the surface, similar to a banana. This defect indicates that the air nozzle is dirty or damaged. The malfunction can be eliminated by cleaning or replacing the nozzle.

The spray of paint is interrupted. There is air in the paint line. In this case, you should check whether there is enough paint in the spray tank and whether the paint nozzle is loose.

There is excess ink at the top and bottom of the print. The problem is solved by reducing the paint supply, which, in turn, is achieved by adjusting the needle and the intensity of the air supply. You can also replace the nozzle with a smaller one. The cause of this defect may also be a malfunction of the needle or screw.

The torch imprint is divided into two parts. The situation can be corrected by increasing the paint supply or reducing the air supply. In addition, you should check whether the vent in the tank.

Not enough paint in the center of the spot. The reason for this defect is that the ratio of paint and air supply is disrupted. To return the torch print to its normal shape, you should adjust these settings.

Lenticular spot. This malfunction is also associated with incorrect paint supply and air pressure settings. In addition, the reason may be that the paint viscosity is too high. The problem can be solved by adjusting the spray gun and diluting the paint with a solvent.

Why doesn't the spray gun work? Many people, most likely, when faced with such a problem, take spanners, different sizes screwdrivers, disassemble the device and try to figure out what could be the cause of the breakdown, and most importantly, how to put it back together correctly, without the remains of the parts that make up the device.

This article invites you to get acquainted with what types of spray guns there are, the reasons for them frequent breakdowns, and how to troubleshoot problems yourself.

Any paint sprayer is a very delicate device and is not suitable for neglect, and breakdowns are not always the reason for the low cost of the tool; this can also happen with a well-known, well-established brand.

Very often the causes of breakdowns can be:

Incorrect operation of the spray gun (see).
Neglect of basic rules when caring for an instrument.

Before disassembling the spray gun into components and parts, you need to become familiar with the types of these tools.

They can be:

Manual(cm. ). Such designs with a manual supercharger, in appearance and principle of operation, resemble a conventional pump. Here, pressure is injected into the cavity with paint independently, and then enters the nozzle.

Such a tool is most suitable for spraying liquid whitewash or a water emulsion of liquid consistency, and with a fully inflated tank it will only last for a few minutes of painting, after which you will need to pump up the pump again.

The main disadvantages of such a tool:

not high working pressure, unable to lift paint of a thicker consistency;
low efficiency and efficiency;
a rapid drop in the working pressure in the tank, which requires constant pumping.

Significant advantages of a spray gun with a manual supercharger - simple design, and not too high a price. This allows any damage to be repaired with electrical tape.

Electric.

Tip: An electric spray gun is a specific tool. When choosing it, you must clearly understand for what tasks it will be used.

Electric spray guns differ in the power of the motor that delivers the paint to the nozzle.

Repairing an electric spray gun is most often associated with a burnt-out engine, which you are unlikely to be able to repair yourself. In addition, the price of a high-quality device is not too low, and it is not always rational to take risks by performing repairs yourself; it is better to pay for repairs to specialists working in the service center.

Pneumatic. This is the most professional tool when painting walls (see). It is the most difficult to repair.

This device consists entirely of mechanical components. There are no complex electronics here, but it often breaks down due to prolonged or not entirely correct use.

Advantages of pneumatic tools:

the ability to adjust the operating pressure, limited only by the power of the compressor and the size of the device’s receiver;
with a pneumatic spray gun you can spray all types of paints, even with a thick consistency, which depends on the settings of the tool;
repairing the unit is quite easy to do independently, without the help of specialists;
By giving the jet the required configuration, it is possible to adjust the spray pattern.

The cost of a pneumatic spray gun varies over a wide range, which allows you to make a choice according to your available funds.

Before repairing any device you must:

Get acquainted with its design.
Correctly diagnose the problem.
Determine the node where the breakdown occurred.

The spray gun contains:

The body of the gun, with a handle, a barrel for paint, and a trigger for feeding the mixture.
Solution injection mechanism, which is equipped with a nozzle and an adjusting bolt.
Spray regulator.
Air supply regulator.

The injection mechanism consists of several components:

A needle that opens and closes the hole for supplying air and coloring composition.
The regulator bolt, when it is turned, paint consumption is controlled.
A locking nut used to hold the needle.
The sealing ring and the hole in it allow air to be evenly distributed around the circumference of the nozzle.
Spray nuts, the part has one hole in the center and two small ones at the edges, which allows you to adjust the size of the “torch”.

Tip: Each product comes with detailed instructions, in which the tool is shown in section. Before work, you should carefully study the design so that after repair there are no “extra” parts left.

How to diagnose the device and possible breakdowns

The table shows the main breakdowns of the spray gun and the reasons leading to this:

Fault name	Causes of failure
The spray pattern is oval and does not respond to changes in the position of the adjusting bolt	The shutoff valve in the adjustment unit has broken off. This problem often occurs with low quality instruments. The side holes in the supply nozzle are clogged. The sealing rubber in the control unit needs to be replaced.
The paint flow is uneven and spits out in chunks	The consistency of the paint is too thick and is not intended for this type of spray gun. There is an accumulation of condensate in the air hoses; it needs to be drained. This occurs very often during the cold season. The holes in the outlet nozzle are clogged. A large amount of solid particles has accumulated in the paint container and cannot pass through the needle. You should drain the composition, rinse the instrument thoroughly and pour in a new composition, but passed through a sieve.
The trigger does not return to the reverse position when released	The piston located on the feed needle is ignited. The instrument is disassembled and thoroughly washed, and the spraying is repeated. The spring located under the bolt that adjusts the feed needle has sagged. Due to rust, the moving mechanisms of the trigger stopped moving. The rubber seal located on the needle has dried out and the piston has moved from its place.
Paint drips from the nozzle when it is closed	The needle became sharp and stopped blocking the nozzle. The sagging spring does not press the needle. Solid particles have entered the assembly and interfere with the correct movement of the needle. The trigger does not recline to the desired position.
The spray pattern constantly changes direction	The hole in the nozzle is clogged. There are clots or foreign objects in the feed mechanism or ink tank. The bolt that adjusts the torch has broken.
The spray gun does not spray paint after pressing the trigger	The needle is not moved by the trigger mechanism. The feed unit is clogged with paint or foreign objects. Very thick paint

Tip: Usually a repair kit for such a tool consists of several bolts and rubber seals, which are supplied with it, but if there are no parts, you should immediately purchase several rubber seals, which quite often deteriorate.

How to maintain and repair a spray gun

For example, a pneumatic spray gun is taken low pressure. The main problem with many units is the use alkyd paints. After finishing work, the sprayer must be cleaned and rinsed well.

Otherwise gun:

It will get clogged.
It will spray unevenly.

Advice: All elements for spray guns should be cleaned and washed - they are all practically “overgrown” with paint, the layers of which must be washed off with solvent or gasoline.

When servicing the spray gun:

The most problems arise with the valve drying to the cylinder, as a result of which it cannot be moved. The use of solvents in this case weakens the dried coating layer and allows the unit to be cleaned. All actions are done very carefully so as not to damage such a small part.
The injectors and nozzle become clogged no less than the valve. In this case, the main part of the unit is the needle, which participates in the formation of the torch and determines the quality of the painting work. To cleanse such small parts a brush with a solvent is used. Here everything must be done very carefully, as can be seen in the photo, in order to prevent the formation of scratches in the nozzle itself, which can cause the paintwork to settle in the grooves and lead to distortion of the torch shape.

When cleaning equipment, it is better to use specially designed SATA needles and brushes that do not scratch the nozzle.
If the moisture separator for the spray gun, which is a filter for the tool and paintwork materials pass through it, is very clogged, then it can be cleaned with the same tools and materials as the nozzle.
It is very important to use paints and varnishes, arriving at the spray nozzle, without lumps, for which the paint container must always be clean. This is due to the fact that the paint that has hardened on its walls will peel off and then mix with the liquid and get into the conductive parts.
If there is a pressure gauge for the spray gun and a pressure regulator, they must be cleaned of dried layers of paint, which can lead to malfunctions in their operation and, therefore, to poor-quality finishing.

After all the cleaning activities have been completed, the sprayer must be reassembled in the same order as disassembly, but after the components and parts have completely dried. You can dry them with a hairdryer. Rubbing elements, including the gun trigger rod and needles, must be lubricated with silicone-free lubricant.

Correct operation Any spray gun will make a good, inexpensive, reliable assistant when carrying out repairs in the house, and the video will tell you how to do it correctly.

(17.05.13) Inessa
Hello! There is no paint supply to the spray gun. What to do?

Hello, Inessa. The reasons for the lack of paint composition in the spray gun may be related to both the device itself and the material used. In addition, this process can be affected by improper use of the gun.

Each individual brand of device has its own instructions for setting the correct paintwork, in particular, the supplied air pressure and paint composition. You must strictly follow the instructions supplied with the device itself. During operation, the user begins to “feel” the device and adjust it, relying only on trial and error. Here are the most common reasons for the lack of yield of coloring material:

Nozzle clogged
Presence of large inclusions in the paint composition
Mesh damage
Blocking the paint channel
Blocking the air supply channel
Needle damage
Factory defect of the device

If you are working with a spray gun for the first time after purchasing it and have not properly checked it in the store, there may be a manufacturing defect. Although this happens rarely. You can replace the spray gun if you keep the warranty card and receipt.

Popular breakdowns and repair methods

But, most likely, the reason is not a factory defect, but the inexperience of the user. Try adjusting the machine using the adjusting screw. Attach a small sheet of whatman paper to the wall and try to improvise with paint, gradually opening the screw. Adjust the supply of paintwork without pressing the trigger of the gun. The screw creates barriers to the movement of the needle and does not allow it to open the outlet for the paint composition.

If adjusting the pressure supply does not change the situation, you need to check whether the needle is dirty. Try to clean the needle and nozzle, repeat the test on paper. If the cause is a damaged mesh, it must be replaced.

Sometimes the spray gun refuses to work when the outlet for the paint composition is fully open. This may mean that you may be using a substance that is too viscous. If large lumps are visible in the mass, grind the coloring composition, then strain on a vibrating sieve. Try applying paint to the Whatman paper in the new consistency, adjusting the pressure with the screw.

Also check the condition of the air supply. After pouring paint into the tank and connecting to the air line, gradually add air pressure. In parallel with the increase in pressure, make periodic short “sprays” onto whatman paper.

Carefully read all instructions for storage and maintenance of the device of a particular brand. Try to wash all the indicated elements of the apparatus immediately after work. Use materials recommended by your gun manufacturer.

Spray gun for home use

Why doesn't the spray gun work? Many people, most likely, when faced with such a problem, take wrenches, screwdrivers of different sizes, disassemble the device and try to figure out what could be the cause of the breakdown, and most importantly, how to put it back together correctly, without the remains of the parts that make up the device.

This article invites you to get acquainted with what types of spray guns there are, the reasons for their frequent breakdowns, and how to troubleshoot problems yourself.

Spray gun device

What are the types of spray guns

Very often, the causes of breakdowns can be:

Incorrect operation of the spray gun (see How to use a spray gun: advice from professionals).
Neglect of elementary rules when caring for an instrument.

Before disassembling the spray gun into components and parts, you need to become familiar with the types of these tools.

They can be:

Manual (see How to choose a manual spray gun). Such designs with a manual supercharger, in appearance and principle of operation, resemble a conventional pump. Here, pressure is injected into the cavity with paint independently, and then enters the nozzle.

The main disadvantages of such a tool:

not high working pressure, unable to lift paint of a thicker consistency;

low efficiency and efficiency;

a rapid drop in the working pressure in the tank, which requires constant pumping.

The significant advantages of a spray gun with a manual supercharger are its simple design and not too high price. This allows any damage to be repaired with electrical tape.

Electric.

Spray gun running on battery

Tip: An electric spray gun is a specific tool. When choosing it, you must clearly understand for what tasks it will be used.

Electric spray guns differ in the power of the motor that delivers the paint to the nozzle.

Pneumatic. This is the most professional tool when painting walls (see Painting walls in an apartment: what to use and how to do it). It is the most difficult to repair.

This device consists entirely of mechanical components. There are no complex electronics here, but it often breaks down due to prolonged or not entirely correct use.

Advantages of pneumatic tools:

the ability to adjust the operating pressure, limited only by the power of the compressor and the size of the device’s receiver;

with a pneumatic spray gun you can spray all types of paints, even with a thick consistency, which depends on the settings of the tool;

repairing the unit is quite easy to do independently, without the help of specialists;

By giving the jet the required configuration, it is possible to adjust the spray pattern.

The cost of a pneumatic spray gun varies over a wide range, which allows you to make a choice according to your available funds.

Spray gun device

Before repairing any device you must:

Get acquainted with its design.
Correctly diagnose the problem.
Determine the node where the breakdown occurred.

The spray gun contains:

The body of the gun, with a handle, a barrel for paint, and a trigger for feeding the mixture.
Solution injection mechanism, which is equipped with a nozzle and an adjusting bolt.
Spray regulator.
Air supply regulator.

The injection mechanism consists of several components:

A needle that opens and closes the hole for supplying air and coloring composition.
The regulator bolt, when it is turned, paint consumption is controlled.
A locking nut used to hold the needle.
The sealing ring and the hole in it allow air to be evenly distributed around the circumference of the nozzle.
Spray nuts, the part has one hole in the center and two small ones at the edges, which allows you to adjust the size of the “torch”.

Tip: Each product comes with detailed instructions, in which the tool is shown in section. Before work, you should carefully study the design so that after repair there are no “extra” parts left.

Spray gun device

How to diagnose the device and possible breakdowns

The table shows the main breakdowns of the spray gun and the reasons leading to this:

Name of the malfunction Causes of the breakdown The spray pattern is oval-shaped and does not respond to changes in the position of the adjusting bolt

The shutoff valve in the adjustment unit has broken off. This problem often occurs with low quality instruments.
The side holes in the supply nozzle are clogged.
The sealing rubber in the control unit needs to be replaced.

The paint flow is uneven and spits out in chunks

The consistency of the paint is too thick and is not intended for this type of spray gun.
There is an accumulation of condensate in the air hoses; it needs to be drained. This occurs very often during the cold season.
The holes in the outlet nozzle are clogged.
A large amount of solid particles has accumulated in the paint container and cannot pass through the needle. You should drain the composition, rinse the instrument thoroughly and pour in a new composition, but passed through a sieve.

The trigger does not return to the reverse position when released

The piston located on the feed needle is ignited. The instrument is disassembled and thoroughly washed, and the spraying is repeated.
The spring located under the bolt that adjusts the feed needle has sagged.
Due to rust, the moving mechanisms of the trigger stopped moving.
The rubber seal located on the needle has dried out and the piston has moved from its place.

Paint drips from the nozzle when it is closed

The needle became sharp and stopped blocking the nozzle.
The sagging spring does not press the needle.
Solid particles have entered the assembly and interfere with the correct movement of the needle.
The trigger does not recline to the desired position.

The spray pattern constantly changes direction

The hole in the nozzle is clogged.
There are clots or foreign objects in the feed mechanism or ink tank.
The bolt that adjusts the torch has broken.

The spray gun does not spray paint after pressing the trigger

The needle is not moved by the trigger mechanism.
The feed unit is clogged with paint or foreign objects.
Very thick paint

Tip: Usually a repair kit for such a tool consists of several bolts and rubber seals, which are supplied with it, but if there are no parts, you should immediately purchase several rubber seals, which quite often deteriorate.

How to maintain and repair a spray gun

For example, a low-pressure pneumatic spray gun is taken. The main problem with many units is the use of alkyd paints. After finishing work, the sprayer must be cleaned and rinsed well.

Otherwise gun:

It will get clogged.
It will spray unevenly.

Advice: All elements for spray guns should be cleaned and washed - they are all practically “overgrown” with paint, the layers of which must be washed off with solvent or gasoline.

When servicing the spray gun:

The most problems arise with the valve drying to the cylinder, as a result of which it cannot be moved. The use of solvents in this case weakens the dried coating layer and allows the unit to be cleaned. All actions are done very carefully so as not to damage such a small part.
The injectors and nozzle become clogged no less than the valve. In this case, the main part of the unit is the needle, which participates in the formation of the torch and determines the quality of the painting work. To clean such small parts, use a brush with a solvent. Here everything must be done very carefully, as can be seen in the photo, in order to prevent the formation of scratches in the nozzle itself, which can cause the paintwork to settle in the grooves and lead to distortion of the torch shape.

How to Clean the Nozzle

When cleaning equipment, it is better to use specially designed SATA needles and brushes that do not scratch the nozzle.
If the moisture separator for the spray gun, which is a filter for the tool and paintwork materials pass through it, is very clogged, then it can be cleaned with the same tools and materials as the nozzle.
It is very important to use paint materials entering the spray nozzle without lumps, for which the paint container must always be clean. This is due to the fact that the paint that has hardened on its walls will peel off and then mix with the liquid and get into the conductive parts.
If there is a pressure gauge for the spray gun and a pressure regulator, they must be cleaned of dried layers of paint, which can lead to malfunctions in their operation and, therefore, to poor-quality finishing.

Proper operation will make any spray gun a good, inexpensive, reliable assistant when carrying out repairs in the house, and the video will tell you how to do it correctly.