The construction of enclosures for pets, the arrangement of water supply and sewage systems, the creation of beautiful stands for plants and many other useful things - all this allows you to make a welding machine. If desired, a simple unit for homework can be assembled by hand. The scheme of the welding machine will differ depending on which model you decide to assemble. The following are guidelines for making the most common options. Study the proposed instructions and proceed to the assembly of the unit that best fits your requirements.
Scheme of a bridge rectifier welding machine, with an indication of polarity when welding thin sheet metal.
Step by step instructions for assembling a simple welding machine
The list of materials and tools required for the assembly of the welding machine will vary depending on what kind of unit you decide to assemble. The following items are basic. Be sure to prepare them, and add everything else as needed. You will need:
Schematic diagram of the welding machine working with electrodes with a diameter up to 4 mm.
- Cotton material.
- Electrical steel.
- Fiberglass fabric
- Copper wires.
- Several screwdrivers.
The welding machine considered in this manual will work with electrodes with a diameter up to 4 mm. It will make it possible to cook metal products with a thickness of up to 2 cm. A schematic diagram of such an installation is shown in the following image: Fig. 1. The welding machine is powered by AC power. Networks are suitable for both 220 V and 380 V.
The scheme of this welding machine is based on a three-phase step-down transformer. Suitable unit with the characteristics of 380/36 V. The power device should be 1-2 kW. There are no special requirements for the base. You can even use an instance with one burnt winding.
First you need to take a transformer and remove the secondary windings from each coil, without disassembling the core. Next, you snack on the copper bus in several different places. Touch the primary windings of the extreme coils is not necessary. The middle should be rewound with the same wire. Every 30 turns create taps. In total, they produce an average of 8-10 pieces. In order not to get confused, it is recommended to put a tag with a personal number on each tap.
Next, you need to wind the secondary winding on the two outer coils until they are completely filled. To do this, use a power three-phase multicore cable. Such a product should contain 3 wires with a diameter of about 7-8 mm and one slightly smaller diameter. Such a wire is able to withstand high voltage. It is characterized by reliable insulation, and thanks to quite a lot of flexibility, the master has the opportunity to do a tight winding without the need for prior disassembly of the apparatus. In total, you will spend about 25 meters of this cable. Instead, you can use a smaller wire cross-section, but in this case the wires will need to be folded 2 times. It is more convenient if you have an assistant. One will be able to lay the coils, and the second will be engaged in pulling the wire.
Winding methods of windings on core type cores.
For the manufacture of terminals on the conclusions of the secondary winding, use a copper tube. A product 3–4 cm long and 1–1.2 cm in diameter will suffice. On the one hand, the tube must be riveted. In the resulting plate is prepared a hole of 1 cm in diameter. On the other hand, you need to insert pre-stripped wires. They should be compressed by small blows of the hammer. On the surface of the tube are made notches core. This will help improve contact.
The panel, which is located at the top of the transformer, must be freed from the standard screws with M6 nuts. Instead, install 2 new M10 screws. It is better if they are copper. You will later connect the secondary terminals to these screws.
Under the conclusions of the primary winding should be an additional fee. To create it, use PCB 3 mm in thickness. The board is attached to the transformer. Before mounting it is necessary to drill 10 holes of 6 mm in diameter each. M6 screws with washers and nuts are inserted into the holes. In case you will connect such a homemade unit to 220 V, 2 extreme windings need to be connected in parallel. The average connects to them in series.
The optimal scheme is in which the welding machine is powered from the mains at 380 V. In this case, you can connect all the primary windings in series. In accordance with the conditions of the circuit, you must first connect the 2 extreme, and only then the middle winding. The terminals of the extreme windings must be connected to a common terminal. The rest are connected to the “Cutting” terminal.
Winding methods of windings for welding machine on toroidal core.
The average winding is needed to reduce the voltage and current in the secondary winding. The holder is made from a ¾ inch pipe. A 25 cm long product will fit. At a distance of 3 and 4 cm from the edges of the pipe on its both sides, it is necessary to cut out the recesses with a hacksaw. The depth of these grooves should be approximately half the diameter of the pipe.
In order to ensure that the electrode is pressed against the holder, take a piece of steel wire and weld it to the pipe over a larger notch. The wire should be 6 mm in diameter. On the opposite side, you need to prepare a hole of 8.2 mm in diameter, take an M8 screw with a nut and a copper terminal, and then connect a piece of cable to the holder.
The cable must be the same from which the secondary winding was wound. At the end, take the hose from caprone or rubber and put it on top of the pipe. At this assembly of the welding machine is almost complete. It is only necessary to figure out what the requirements under the terms of the scheme are presented to connect and work with such a device.Back to table of contents
Connecting and using a homemade device
Wiring diagrams for welding machines.
To connect such a welding machine will need wires with a cross section of 1.5 mm2. The unit is connected through a switch. One wire goes to pin "1" - "8" (select the specific one according to the welding current), and the second one will go to the "Common" terminal.
The most powerful current you can get at the terminal "Cutting". At the primary winding, the current will be no more than 25 A. The secondary winding has a current of 60-120 A. Remember that the circuit of such a welding machine does not imply its use for large volumes of work. Having consumed 10-15 electrodes 3 mm in diameter, be sure to let the unit cool down. If you work with 4 mm electrodes, you will need to give the device more rest more often. Work with electrodes for 2 mm of such forced breaks will not require.
The fastest welding machine heats up when working in the "Cutting" mode. In this case, it will require much more frequent rest. You can cut almost any metal. The device copes with products of "household" thickness without any problems. When changing welding modes, be sure to turn off the power switch for your own safety and tool safety.Back to table of contents
Scheme of the device from car batteries
Figure 2. Scheme of the welding machine from car batteries.
Craftsmen come up with a variety of schemes of welding units. If desired, you can even assemble a welding machine from car batteries. When carrying out welding works, the electrical network under a load of 3.5 kV is sinking by voltage by 30 V and more. Of course, you could spend the money to buy a separate power plant for welding, but it’s much more convenient and more profitable to go the other way.
You just need to take 3-4 batteries at 55-190 A / h (preferably, this figure was higher). Batteries are connected in series. Suitable materials such as wires, clamping pliers, lighting wires, etc. are suitable for connection. The scheme allows the use of already used batteries for the welding machine assembly. The basic scheme presented in the following image will help you assemble the unit with your own hands: Fig. 2
Absolutely nothing complicated in the design of such a welding machine. The scheme is very simple and straightforward. However, even despite the ease of assembly and simplicity of design, this device cooks beautifully. Be sure to check the electrolyte level at least once a week. During the working day, the batteries heat up quite strongly, especially if it is summer outside, and the water evaporates at a rapid pace.
There are advanced schemes of the welding machine under consideration. For example, you can additionally assemble a charger for the device, which will save you from having to charge each battery separately. Enough to put the unit to charge at night, and in the morning you can safely work with him.
Figure 3. Assembly scheme of the welding machine for soft welding.
When working with an electrode of 3 mm, such a welding machine develops a current of 90-120 A. Accumulators can withstand a load and 2 times more load, so no problems should arise if everything is done according to the conditions of the earlier scheme.
The output voltage will vary according to the number of batteries used to assemble the device. It varies in the range of 42-54 V. The current strength of the device is 1/10 of the capacity of 1 battery in the unit. For example, if you take 55 A / h, then the charging current will be no more than 5 A.Back to table of contents
Scheme and assembly of the machine for soft welding
There are proven device circuits with rectifiers. Such models operate on direct current. They are characterized by higher performance, than "variable". But they also need to customize and bring. The scheme of the unit has been slightly improved. The changes made to the scheme allowed to make the welding process softer. The direct diagram of such a unit is shown in the following image: Fig. 3
The apparatus includes a capacitor C1. It is placed between the negative and positive wires of the rectified current. An electrolytic capacitor of 15000 uF is used. Use a device designed to operate at a voltage of 100 V.
Welding machine for soft welding.
Thanks to this capacitor, a reliable and at the same time smooth arc burning will be provided. If you are limited in finances or cannot find such a capacitor, replace it with C1 = 50 μm x 160 V. Only in this case it is necessary to install a capacitor already in the positive half-current circuit.
It is recommended to install a paper capacitor with a capacity of 160 microfarads and an operating voltage of 500 V. It is recommended to install MBGI, MBGO capacitors, etc. in the primary circuit. Thanks to this element, power surges will be smoothed.Back to table of contents
Build a semi-automatic do-it-yourself
Automatic welding semiautomatic device with electronics is useful in any household. It works in a protective environment of carbon dioxide. Such a unit is indispensable for welding thin-sheet metal, repairing vehicle bodies and other similar works.
It is assembled from available materials, components and parts. It is necessary to have minimal skills in metalworking and turning.
If you encounter any difficulties with radio and electrical equipment, it is better to immediately contact an experienced radio amateur to save time and avoid difficulties.
Figure 4. Schematic of a semi-automatic welding machine with electronics.
The schematic diagram of such a unit is shown in the following image: Fig. four.
This diagram contains the following notation:
- Position a - throttle.
- Position b - welding transformer.
- Position in - rectifier.
- Number 1 shows the magnetic cores.
- Position 2 - textolite. In the case of a transformer, it is an insulating tape.
- Number 3 - bus or wire.
- Position 4 - diode VL200. It will take 2 pieces.
- Number 5 - diode B200. Also need 2 pieces.
- Under number 6 is a section of dual radiators in the amount of 2 pieces.
- Position number 7 is assigned to studs with washers and nuts. A total of 4 sets.
Features of the homemade semi-automatic
Schematic diagram of the semi-automatic.
Each thyristor of such a device will work only if there is a corresponding half-period of the line voltage of the anode. The welding transformer in such a scheme has no particular differences from other similar devices. The primary winding make 220 turns of copper wire. The best wire diameter is 1.9 mm. It is desirable that he was in glass cloth insulation. 56 turns of a tire or a multicore cable with a cross section of 60 mm2 will suffice for the secondary winding.
Each rectifier bridge diode is recommended to be equipped with a radiator with a heat transfer area of 200 cm2. This will improve cooling. Before starting work with such a welding machine, move the guides to the rollers as far as possible and tighten them with nuts. Then pass through the guides, the mechanism, the torch and the tip of the welding wire. Screw the tip into the burner channel, then put on the protective cover. Last you need to tighten a screw. Connect a hose from a carbon dioxide bottle with a reducer to a pneumatic valve. Using a pressure reducer, set the gas pressure to 1.5 atm. Turn on the power, adjust the wire feed speed with resistor R7 and get to work. When working with such a homemade semi-automatic, use a wire with a diameter of 0.8-1.2 mm.
After a few small workouts, you can get welds with quality no worse than you would get when working with factory-assembled equipment. But homemade units cost much more profitable than ready-made solutions. Have a good job!