Sandblasting is a universal device that is used in industrial and domestic environments. It can be used to clean the surface of the layer of the old coating, dirt, corrosion.
There are several ways to become the owner of such a useful device in the household. The first is to buy a ready-made version in the store. This is the easiest way. Its only disadvantage is the high cost. The second way is to assemble the sandblast with your own hands. This will require some effort, but in terms of material costs, this method is much more economical.
How the device works
To understand how to make a sandblaster with your own hands, you need to know how it works. It is similar to the operation of an airbrush used to spray paint (and other coatings).
The main element of the installation is the compressor. It pumps air, creating the necessary pressure in all lines. Passing through the installation, the air creates a vacuum. Due to this, the abrasive material (sand) is mixed with air and enters the main line. From there, the flow passes to the nozzle, through which it exits. At the outlet, a stream of air with sand is created, which moves under high pressure. It is he who is sent to the surface to be treated.
The diagram of the sandblaster is shown in the figure.
Main installation items
Homemade sandblasting consists of the following parts:
compressor;
electric cable for connecting to the electrical network;
hoses of a certain diameter;
fitting for connecting elements;
faucets;
dispensers
Nozzle
Another important element is the nozzle, without which the device will not be able to perform its functions. The nozzle for the sandblaster at the enterprise is made of steel and coated with boron or tungsten compounds. This gives the part durability. Less often, ordinary steel, ceramics or cast iron are used for production. But such elements are quickly destroyed under the influence of a stream with abrasive material.
At home, the nozzle for a sandblaster can be turned on a steel lathe using old spark plugs as a material. To do this, they take out a metal electrode, which is located inside the candle. True, such a mechanism is characterized by a short service life, because it wears out quickly. But its cost is very low.
Types of devices
Described abovethe device is typical for suction sandblasting equipment. But this is not the only version of the device. There are only 3 types of sandblasting:
Suction. This option is easiest to make at home. It is suitable for cleaning surfaces at a light stage. This option differs in that air takes sand from the container and delivers it in the form of a stream
Vacuum. This type of equipment operates in a cyclic mode. This means that the abrasive material is ejected to the surface through the nozzle, after which it is sucked back into the chamber for reuse
Pneumatic. This type of equipment is used to work on large areas or in hard-to-clean places. Homemade sandblasting of this type is a dangerous device in terms of safety. Therefore, it is not recommended to collect. This is due to the high pressure in the system and high power
Air or water may enter the abrasive supply. The first option is more common, since its design is simpler.
Abrasive feed
The abrasive can be supplied in two different ways, depending on which sandblasters are divided into injection and pressure.
Pressure devices are characterized by high performance and work intensity. In them, air enters simultaneously into the apparatus itself and into the container with sand.
The injection method for supplying sand is characterized by low pressure, so it is used,when they collect sandblasting with their own hands. In this case, air and abrasive material move along different lines.
What you can build yourself
Making devices at home involves using materials that you can easily find in your garage. In addition, simple designs are used that work effectively. Given this, you can be guided by a simple diagram, without any drawings.
As a container for abrasive material (receiver), where sand should be poured, you can use a gas cylinder. The hole for filling the balloon is located on top. Air under pressure will enter the receiver through a pipe mounted in the upper part of the cylinder, and, together with the sand, will exit through the exhaust hose located below.
Materials for making the apparatus
The drawings of the sandblaster make it clear what parts are needed for its manufacture and in what sequence they need to be connected. One of these drawings is shown in the figure below.
The need to purchase a compressor, which is the main element of the device, was mentioned above. Its capacity should be at least 800 liters. It will need an oil separator to keep the sand from getting wet.
In addition to the compressor, you will need a container to accommodate the abrasive material. Very often, a gas cylinder is used for this, the capacity of which is 50 liters. Its design allows it to withstand high pressure inside and mechanicaloutside damage.
A filter for running water is useful, in which it is possible to replace the filler. Instead of a filter element, silica gel in balls will be poured into the flask (you can buy it at a pet store). The filter is necessary to dry the air before it enters the receiver.
The duration of continuous operation largely depends on the selected nozzle. Inexpensive options (made of cast iron or ceramics) are designed for several hours of operation. In some cases, they only last a few tens of minutes. Therefore, it is better to give preference to parts made of boron carbide or tungsten carbide and capable of withstanding hundreds of hours of intense work.
In addition, the following parts will be needed to assemble the device:
oxygen hose for air supply (length 5 m and inner diameter 10 mm);
reinforced hose (length 2 m and inner diameter 2 m);
fittings for hoses for connecting individual parts of the device with a rubber hose into a single system;
collet clamp;
brass ball valve (2pcs)
pipe with thread and plug (the neck will be made from it);
a piece of pipe with the same diameter and three barrels;
sealant for joints (fumlent)
When all the parts are assembled, you can start assembling the sandblaster.
Assembly steps
Homemade sandblasting is assembled in the following sequence:
Preparation of the balloon. If a used cylinder was purchased, it must be emptiedfrom gas. To do this, the valve is twisted completely. The entire container is filled with water, which will displace the remaining gas. After that, work with the cylinder will be safe. Instead of a neck, we fasten a branch pipe with a ball valve. A tee is screwed into it from above, into which two fittings are inserted
Supports are welded from 3-4 pieces of reinforcement from the top side of the cylinder. They must be long enough so that the crane does not touch the ground
In the middle of the bottom of the cylinder, a hole is made where the tee is welded. One tap is required for the cork. The second is for the air supply hose (a tubular extension is welded). All connections are recommended to be welded to ensure tightness. It can be threaded, but then a sealant must be used
A flow filter is attached to the tubular extension using a tee. To the tee - a hose, which at the second end will be connected to the fitting at the bottom of the cylinder (near the supports). Connections are fixed with clamps. A ball valve is placed at the inlet of the filter. A fitting is fixed to it, through which the hose coming from the compressor will be connected
The gun is assembled from a nozzle, which is connected through a piece of hose to a ball valve. The other end of the faucet is connected to a metal tube (approximately 30 cm)
At this stage, the homemade sandblaster is ready. Handles can be welded on the sides of the receiver. This will make it easier to carry.
