A semiautomatic welding machine in the hands of a person who knows how to use equipment is a multifunctional and useful device. Thanks to him, the zealous owner of a suburban area can always manufacture various metal structures, as well as engage in minor car repairs without resorting to outside help.
Of course, you can purchase a welding machine in a distribution network, since the industry currently offers a huge number of models, but this can seriously hit the family budget. Therefore, craftsmen, having found the necessary parts and assembly scheme, try to do the welding semiautomatic device with their own hands.
In principle, the circuit of such a device does not differ in particular complexity. With a little knowledge of electrical engineering and the ability to carry out locksmith work, you can safely proceed to the manufacture of a semi-automatic welding machine yourself.
Welding Features
A traditional welding machine is a transformer that has a secondary winding of high power. Welding ferrous metals and steel with the help of such a device is not particularly difficult, but they will not be able to cook copper, aluminum and other non-ferrous metals.
And this is explained very simply: parts from non-ferrous metals and alloys in the open air are very quickly oxidized, so their connection does not occur. To protect the weld, it is necessary to feed elements into the welding zone that can limit the access of oxygen.
This work can be carried out most qualitatively by home-made welding semiautomatic devices, which are divided into the following types of protection:
- Welding takes place under the protection of flux.
- The compound is formed in an inert gas atmosphere.
- The docking process takes place using electrode flux-cored wire.
The main condition for a strong and high-quality connection is stable arc burning, which is achieved by using direct current.
Homemade device
The principle of operation of a semiautomatic device for welding is based on the conversion of an electric current of variable frequency into direct current. Moreover, it is necessary to feed a welding wire and protective inert gas to the junction.
These operations are carried out by the following main components, a self-made welding semiautomatic device:
- Inverter device.
- Welding wire feed unit.
- A set of protective gas equipment.
Despite the apparent complexity of the concept of a welding semiautomatic device, it is not difficult to make it to a person who is familiar with the principles of electrical engineering.
Making a homemade fixture
Doing it yourself with a do-it-yourself welding semiautomatic device is recommended with planning the location of the main components of the unit. First of all, you need to carefully consider what to make the external case of the unit from. It should be roomy, easy to open and close for cleaning, and also, importantly, have a small weight.
The most optimal option is the use for these purposes of the case from the old system unit of a personal computer. The presence of ready-made cutouts for cooling is a huge advantage of its use.
Also, in such a home-made welding semiautomatic device from the computer, there is already a built-in power supply with a voltage of 12 V, which is necessary to power the wire feed system. If you still could not find the system unit, then for the outer case a metal box of the appropriate size is quite suitable.
Welding wire is best used in standard 5 kg bobbins, as their inner diameter is in good agreement with the polyethylene pipe used for the axis of rotation.
After analyzing and arranging the elements for the manufacture of a welding semiautomatic device with your own hands, we proceed to alter the necessary nodes.
The main components required for the apparatus
Of course, before you make a welding semiautomatic device, you need to prepare in advance the necessary components of this device. For these purposes, you need to prepare:
- The device that will generate a working current of 150 A is an inverter. For a homemade welding semiautomatic circuit, masters often use a transformer from a household microwave.
- The electrical unit that is needed to control the unit.
- Burners for special purposes.
- A sleeve for a semiautomatic welding machine necessary to supply protective gas to the welding site.
- Welding wire feed unit.
- A bobbin with wire.
Considering that all equipment is heavy, many welders recommend making a cart for a semi-automatic welding machine with their own hands.
Transformer manufacturing
For a welding semiautomatic device, a transformer from a microwave oven is suitable for many technical parameters. This product consists of two coils with copper wire. The primary winding of the transformer remains unchanged.
All operations for the conversion of a welding transformer for a semiautomatic device will be performed on the secondary winding. To reduce the operating voltage and increase the output current, it is necessary to rewind the secondary winding. In this case, it is necessary to correctly calculate the diameter of the copper wire for the coil, because both high and low voltage at the output significantly affect the quality of the weld.
Rewinding operations must be carried out with extreme care so as not to damage the insulation of the conductors.
To obtain a stable output voltage, the electrical circuit of the supply unit also includes a rectifier bridge, capacitor and inductor. The use of a capacitor is necessary to smooth the voltage ripple at the output of the rectifier. The inductor serves to stably maintain a given level of operating voltage.
Gas-burner
The use of this device is due to the need to supply protective gas to the place of formation of the weld. Most often, this fixture is purchased in a distribution network, since it is very difficult to make it yourself, especially since for the DIY welding machine made using expensive models is not necessary.
Too hard a hose makes it difficult to work with equipment, while a soft one is capable of bending. Therefore, special attention should be paid to the quality of the sleeve for a welding semiautomatic device. Eliminate kinks near the connection points by inserting additional springs.
Wire feeder
The main condition for creating a high-quality weld is a uniform and continuous supply of wire to the welding site. For these purposes, a home-made welding semiautomatic device is equipped with a wire feed system.
To make the feed unit you will need:
- Two bearings, one of which is clamped (adjustable).
- Clamping spring.
- Guide roller.
- Electric motor for shaft rotation.
- Mechanism mounting system.
The electric motor is powered from the built-in power source, which is located in the system unit. If the case is assembled from a separate device, you must assemble an autonomous power supply circuit.
Mechanism assembly steps:
- On a special metal plate, we drill holes for mounting bearings, as well as an electric motor shaft.
- An electric motor is attached to the back of the plate.
- A guide roller is mounted on the drive shaft.
- Bearings are fixed in the upper and lower parts.
Cooling system device
When operating a welding semiautomatic device, the secondary winding of the transformer is heated. Therefore, it becomes necessary to cool the unit. For these purposes, fans must be installed on the sides of the housing. They are installed opposite the transformer, while they must be configured to extract heated air.
To improve air circulation, it is necessary to drill 20-50 holes with a diameter of about 5 mm in the casing.
Remember that high-quality and efficient cooling of the electrical part of the welding equipment has a positive effect on its performance.
Optional equipment
It is customary to purchase a standard-type gas cylinder, because when working with gas mixtures, equipment safety measures often come first.
The use of carbon dioxide to protect the welding site allows the use of extinguisher tanks as cylinders. In this case, you still have to install a special adapter for connecting the gearbox.
To increase the mobility of work, welding semiautomatic devices for summer cottages and suburban areas are equipped with special trolleys. You can purchase finished factory products, but experienced craftsmen prefer to make carts on their own.
Each specialist can develop the design of this device with his own hands. Materials can also be of various types (channel, round or profile pipe).
Some features of operation
Do-it-yourself semi-automatic welding equipment requires a certain attitude to its effective operation. Remember that a home-made device is not suitable for professional activities.
It is imperative that at least once every 3-6 months, the equipment is completely cleaned of dirt and dust. With increased use, this operation can be carried out more often. Experienced welders recommend cleaning equipment after each use.
Of course, modern industry produces a wide range of models of welding semiautomatic devices, but each prudent owner prefers to make this device on his own. This is not only cost savings, but also the ability to make an assembly that meets the requirements of the master.