How to make a welding machine with your own hands

Alone to make the welding machine makes sense when it is necessary to carry out relatively small volumes of welding work in household conditions. Knowing the basic principles of the device, you can collect it from easily accessible parts and materials.

First of all, it is necessary to determine which power welding current will be required in operation. Obviously, for the processing of thin metal sheets up to 2 mm, a much smaller current intensity is needed than for massive reinforcement. Depending on these characteristics of the material, the diameter of the electrode is selected. For the welded parts with a thickness of up to 2 mm, the electrode 1.5 - 3 mm in diameter. Accordingly, for parts 3-5 mm - electrode 3-4 mm, parts up to 10 mm - electrode 4-5 mm, parts up to 24 mm - electrode 5-6 mm and parts up to 60 mm - electrode 6-8 mm.

Determining the diameter of the electrode, select the desired value of the welding current. Electrodes with a diameter of up to 1.5 mm are suitable for welding current 4O A, 2 mm - 70 A, 3 mm - to 140 A, 4 mm - up to 200 A.

In any apparatus for the formation of a welding arc network voltage directly affecting the material, a transformer is used. In professional devices, it is equipped with various devices for strengthening and improving the quality of the welding arc. In domestic homemade welding machines, you can restrict ourselves to the transformer without additional devices. The transformer consists of a magnetic pipeline that can be assembled independently from plates of special transformer steel, primary and secondary windings. The primary winding is turned on directly to the 220V network. It can have special taps that allow you to adjust the current intensity at the output. But homemade devices, as a rule, are not complicated by such discharges, and initially configured to a certain power of the current. Welding is made from the second winding.

The power of the transformer is selected in accordance with the required intensity of the welding current. It is calculated by the formula P \u003d 25ISV, where the value of the welding current is measured in amperes. The cross section of the transformer magnetic pipeline (S) must be at least r * 0.015, where P is the previously calculated power. The diameter of the primary winding wire is 1.13 (P / 2000) in the square. The choice of the diameter of the second winding depends on the current density measured in A / mm2. When current up to 100a, the density will be 10a / mm2, to 150a - 8a / mm2, to 200a - 6a / mm2. Thus, the exact section of the secondary winding can be determined by the formula 1.13 (I / J) in the square, where I is the value of the welding current, J is the current density. The number of turns of the wiring is proportional to the magnetic pipeline cross section and is defined as W \u003d S / 50, where S is the cross-sectional area of \u200b\u200bthe magnetic pipeline.

The softness or rigidity of the welding process depends on the external characteristic of the welding current, which, in turn, is formed by the value of the voltage at the clips of the output terminals. The outer characteristic may be a cool, whipping, increasing and rigid. In self-made machines for manual welding, it is advisable to use current sources with a cool or weighing characteristic. Current fluctuations when changing the welding arc are small, so such devices are ideal for welding in living conditions.

The welding machine made independently with the use of carefully selected components can fully replace the expensive finished apparatus and reliably serve the owner for many years.