In the arsenal of each motorist must have a compressor. A homemade unit often works better and more reliable than equipment from the store. And if you look at the prices at which such a device is sold, it becomes clear why more and more people from the materials at hand assemble the compressor with their own hands. A home-made installation will serve for a long time and without failure, if you approach the selection of components with knowledge of the matter and carry out assembly in a quality manner. This article is dedicated to this topic.
Professional compressed air
The compressor will never stand idle in the dark remote corner of the garage. He will always find application: from eliminating fine particles from the workplace after abrasive processing and grinding to applying paintwork on the car body or other surfaces. Such a compressor is also indispensable if there is a need to dry parts or assemblies of mechanisms before assembling or disassembling them, as well as when cleaning products from lubricating coolant after machining on metal cutting machines.
Compressor quality
Painting works are very responsible, since the appearance of the car depends on them. This imposes certain requirements on the build quality and operation of a homemade compressor. Air supply should be carried out uniformly throughout the area; no, even short-term gusts and slowdowns are permissible. Air pollution by oil vapors of the pumping system and other foreign substances is not allowed.
Homemade compressor from the refrigerator
It is possible that the first attempt to assemble the ideal compressor will fail, and in order to use it for its intended purpose, it will be necessary to debug the work. With a purchased unit, at least in the first months of its operation, there should be no problems. But the cost of garage equipment today makes you open your mouth in surprise. In other words, buying a branded unit is not always justified and affordable for a simple motorist. Especially when it comes to quality equipment released under the brand name of a famous brand. It’s best not to pay attention to cheap analogues: they will cause more trouble than good.
According to the assurances of many gurus in the repair and maintenance of automotive equipment, a homemade compressor could well compete with expensive equipment. At the same time, you can assemble such an aggregate from improvised materials, saving a lot of money on this. Such work is beyond the power of any person who knows how to work with a wrench. It is enough to familiarize yourself with the instructions and recommendations of the masters.
Operating principle
The principles of operation of a homemade compressor and a purchased one are no different: the same laws of physics and similar solutions are used. The factory unit has a more complex design, but often this is its weak link: instead of increasing the reliability of the system as a whole, complex components and mechanisms often fail and there is a need for repair.
The essence of the compressor is as follows. In a metal tank (receiver) air is stored under pressure, an order of magnitude higher than atmospheric pressure. Air in the cylinder can be supplied either manually (using a hand pump), or through an electric pump. Assembling the first option will cost much less, but working on such a device will be an order of magnitude harder. In principle, if such a makeshift compressor is planned to be used infrequently, then perhaps it will suit you. However, today it is possible to easily get all the necessary components and parts necessary for assembling a compressed-air compressed air generation unit with a mechanized drive. In most cases, the donor of the engine is some old refrigerator. A homemade compressor from it turns out no worse than bought from the store. The refrigerator engine (especially in the old Soviet times) is very reliable. It will ensure the smooth operation of the installation.
Necessary components
In order to assemble a very simple compressor, it takes a little time and some details. Namely: the compressor itself, the container for storing compressed air (the old gas cylinder is perfect), the valve from the old car camera, an awl, all kinds of fasteners (to collect all the disparate components in the installation on wheels). The main and most important element of the entire system is the engine. The automobile compressor from ZIL-130 is well suited. A homemade compressor from such components will last a long time and will hardly let you down at the most crucial moment.
But this will be a very simple installation, which may not be able to be used in carrying out critical work. It is better to spend more time, but assemble a device of a professional (semi-professional) class. List of components that will be needed during the assembly process:
- pressure sensor (manometer);
- gas reducer (for regulating the outlet pressure and smoothing the shocks);
- a relay that will, for safety reasons, shut off the power supply to the installation at an increased pressure in the tank;
- fuel automobile filter (can be replaced with a special air filter);
- hose clamps;
- water splitter (quadruple with a female thread ¾);
- receiver (a gas bottle is suitable);
- oil (semi-synthetic);
- power supply button for the installation (toggle switch);
- brass tubes;
- connecting hoses (resistant to oil products);
- fasteners (screws, bolts, studs and nuts of the required diameter);
- paint for metal (it is best to use aerosol);
- anti-corrosion agent (phosphoric acid converter);
- file;
- base (wood or plywood board or sheet metal);
- wheels for furniture.
How to make a homemade compressor?
In order for the unit to be conveniently stored and moved from one place to another, all elements must be equipped and mounted on a base with wheels. As a rule, an ordinary wooden or plywood board is used for these purposes. The receiver is fixed to it (gas cylinder or extinguisher body with an expired shelf life). As a supercharger, a ZIL automobile compressor is used. A home-made compressor from these elements will have small dimensions and can easily be stored in sections.
To fix the compressor itself, use medium-diameter bolts. The compressed air cylinder is installed in an upright position. It takes three sheets of plywood. In one, a hole is cut along the diameter of the cylinder. This sheet is attached to the board, and a balloon is placed in the hole. The other two fix the balloon on its sides.
Work with the engine
Work begins with a functional check and installation of the central unit element - the engine. It is he who will pump air into the receiver, which means that the operability of the entire device depends on his work. As a rule, they use a motor of an obsolete refrigerator and a morally obsolete refrigerator, or a compressor from a car.
The refrigerator engine already has a relay, which is necessary to maintain the set pressure. According to people who have assembled more than one compressor in their life, old Soviet engines can give odds to even the most modern Japanese units. It sounds fantastic, but it really is.
So, first of all, the engine is dismantled from the refrigerator. This element is always located below, under the radiator grille at the back of the refrigerator.
It is imperative that the oil be replaced. Without this, engine life will be limited.
Three brass (copper) tubes extend from the motor. One of them is with a plug installed. The other two are open. One of the open tubes is the input channel, the other is the output channel. To uniquely identify the input and output tubes, you need to turn on the engine and put your finger on one and the other tube. If the finger is attracted (sucked in), then the tube is the input. If on the contrary - it is pushed out by a stream of air, then the outlet pipe. It is necessary to somehow label these elements so as not to confuse them in the future.
The sealed tube must be unpacked (opened) to replace the oil. To do this, a small incision is made with a file or a hacksaw blade. Then the tube breaks. The notch should be minimal and not cut the wall of the tube to avoid metal sawdust entering the system.
System dust protection
To extend the life of a makeshift compressor, an air filter is installed at the inlet. It will trap large particles of dust and abrasive, preventing them from entering the system.
The air filter and the inlet of the air blower are connected through a rubber hose. It is not practical to use a metal tube in this case: the inlet pressure does not exceed atmospheric pressure, which means that there is no need to increase the stiffness of the tube.
Cleaning compressed air at the outlet of moisture and oil vapors
There are strict requirements for equipment that is used for painting cars. A home-made compressor used for these purposes (however, like the factory one), must ensure high purity by extraneous impurities at the air outlet from the nozzle. Therefore, it is imperative to install a cleaner. The fuel filter for any car will perfectly cope with the role of this. A homemade compressor for painting is equipped with this device at the outlet of compressed air through an oil resistant hose. The outlet pressure reaches an impressive size, so automobile clamps are used for all connections. This greatly increases the reliability of the system and prevents spontaneous disconnection of hoses during operation.
The filter, in turn, is connected to the gas reducer.
Compressor start
Before commissioning the assembled installation, it is necessary to test it. The operation of the compressor is fraught with danger - work is carried out with high-pressure vessels. A homemade compressor should have a sufficient margin of safety, allow you to adjust the pressure in the receiver and at the outlet of the compressed air, and run smoothly.
After assembly, the unit is connected to the outlet hose with a spray gun.
System pressure control and leak test
The receiver pressure is controlled by the pressure gauge. Before starting the compressor, the knob is set to the minimum mark. Gradually, the pressure increases. In this case, the pressure gauge needle must change its position (with increasing pressure - it moves to the right clockwise, with decreasing - to the left).
At the junction of the hoses apply a soap solution. If it begins to bubble - this indicates a leak, which means that it is necessary to tighten the clamp or replace the connection.
After checking the system for leaks, air must be vented from the tank. After reaching a pressure lower than the set pressure, the engine start relay should automatically operate, and the pressure should reach the indicated norm.
A homemade compressor for painting without fail passes all the described stages of control before it is allowed to work.
Compressor Maintenance
A self-assembled compressor from improvised materials is simple and reliable. Therefore, he does not need expensive technical service, which can not be said about capricious purchased equipment. It is enough to change the oil only once a year and occasionally clean the filters so that the apparatus works for many years and conscientiously fulfills its duties.