Welding semiautomatic device: do it yourself at home - Setafi

The welding machine is in demand among metalworkers. It is used for joining, fusing, repairing metal/metal alloy surfaces. Welding is not cheap, so not everyone can afford it.

In this article, we will analyze how to make a semi-automatic welding machine with our own hands, what you need to create a welding machine at home, what are the features of making home-made welding.

Peculiarities

To make semi-automatic welding at home, you need basic knowledge in electronics. The easiest way to do welding is to remake an inverter or transformer. Inverter power should be 150 amps or more.

To make homemade welding, you will need the following materials:

• Electrical control system.
• Gas supply hose/guide sleeve.
• Protective gas cylinder (argon, carbon dioxide).
• Bobbin/coil.
• Filler wire and a device for its supply (a power window from a car is suitable, it will need to be adjusted).
• Transformer or inverter (power more than 150 A).
• Burner.

You will also need a body. You can do without it, but it is inconvenient and unsafe both for you and for the device itself. As a case, you can use a microwave or a system unit from a computer.

The whole process of manufacturing a semiautomatic device is to connect the finished elements. It is not necessary to change them, except for the mechanism for feeding wire and gas, the rest work in finished form. The wire feed mechanism must be adjusted so that the wire is fed at the melting speed. The wire feed speed is affected by its diameter, the material of manufacture (copper, steel), as well as the material being welded (metal, alloy). Take this into account when making adjustments. We recommend adjusting the speed before each welding job.

How to do welding at home. Semi-Automatic Crafting Tips

First you need a diagram/drawing. They are freely available on the Internet. They may differ depending on the welding model, but there are no differences in the main components, so you can use the generalized drawings.

Further, if you are using a power window for wire feed, you need to adjust it, because the quality of welding depends on this directly - the wire must be fed smoothly, evenly and at a speed welding. To adjust the power window, use the PWM controller. The feed delay can be done using a relay. The relay can also be taken from the car. Instead of a relay, you can use an electric valve, put such valves on cylinder gearboxes.

Adjust the gas supply mechanism. If the gas is supplied too late, the electrode may ignite - the seam will be of poor quality, weak and uneven, the surface may be damaged. In a properly configured semiautomatic device, it is protected by a “bathroom” of protective gas.

To regulate the gas supply, open/close the gas valve. The correct setting is that gas is applied a few milliseconds/seconds earlier than the circuit is closed/welding starts.

Preparation

The transformer is the most important element in a welding machine. It changes the voltage and feeds the working part. The household electrical voltage is too high for welding to work, so the transformer steps down the voltage. You can take a transformer for homemade welding from an ordinary microwave.

Transformers from microwave ovens step-up type - increase the voltage from the network. Welding requires a step-down type, so the microwave transformer must be converted before being used in welding. To do this, change the number of turns on the primary and secondary windings. So you change the transformation coefficient.

For a standard transformer, 100 turns per primary circuit are suitable, 5 for the secondary. At the output, you will receive a voltage twenty times less than in the network (11 V).

The number of turns is written without taking into account the basic ones - that is, there should be a total of one hundred turns on the primary circuit, and only five on the secondary. Most of the problems arise at this stage - users remove too much wire, there is a lot of voltage in the network, the wire does not withstand, the wiring ignites. Or, on the contrary, few turns were removed - the voltage does not decrease enough, the current is weak, welding simply cannot cook.

Do not rush, accurately calculate the number of windings, the cross section of the wires.

Frame

There are few requirements for a housing for a home-made welding machine - it does not affect the performance of the device. Welding itself consists of many parts, wires, elements. To conveniently and safely use the device, you need to assemble them into a case. A microwave oven, a system unit from a personal computer, or you can make it yourself is suitable as a basis. If you decide to make the case yourself, then use thin sheet metal. Make a drawing in advance, taking into account all the sizes of the parts.

When calculating, installing elements, allocate space for cooling. For cooling, use two through fans / coolers from the computer. They should work only for blowing. Do not place parts close together, they may overheat.

Two coils must be connected in parallel, the other two in series. This method will provide a high direct current.

Control system

To make a control system for a homemade welding machine, you need:

• Generator (setting type).
• Relay.
• Feedback.
• Overload protection.
• Control board.

Connect the control board to the transformer block. Bring the rest of the elements to it - generator, relay, protection, fan / cooler. Through the board, connect home-made welding to the mains. Before working on such welding, it is necessary to check the operation of the control system and working units. Use an oscilloscope, connect it to the outputs.

How to use homemade welding

As usual:

• Insert the wire spool, inspect/check the device. Also check how the gas supply hoses are connected and open the cylinder.
• Clean up work area and ground, install ground.
• Connect the welder to the mains and wait.
• Turn on the wire feed, start cooking like a conventional semi-automatic.