It is very convenient to work in any metal processing workshop if you have a welding machine at hand. It can be used to securely connect metal parts or structures, cut holes, or even just cut the blanks in the right place.

Such useful tool you can do it yourself, the main thing is to get it right in everything, and the skill to make a beautiful and reliable seam will come with experience.

AC output current

At home, in the country, at work, such devices are most often found. Many photos of welding equipment show that it is made by hand.

The most important components for such an apparatus are a wire for two windings and a core for them. In fact, this is a transformer for lowering the voltage.

Wire dimensions

The device will work quite well with an output voltage of 60 volts and a current of up to 160 amperes. Calculations show that for the primary winding, you need to take copper wire section 3, and preferably 7 square millimeters. For aluminum wire, the cross section should be 1.6 times larger.

Wire insulation must be fabric because the wires get very hot during operation and the plastic will simply melt.

It is necessary to lay the primary winding very carefully and carefully because it has many turns and is located in the zone high voltage. It is desirable that the wire be without breaks, but if the required length is not at hand, then the pieces must be securely connected and soldered.

Secondary winding

For the secondary winding, you can take copper, or aluminum. The wire can be either single-core or consisting of several conductors. Cross section from 10 to 24 square millimeters.

It is very convenient to wind the coil separately from the core, for example, on a wooden blank, and then collect transformer steel plates into a finished, reliably insulated winding.

stranded wire

How to do stranded wire suitable section for the welding machine? There is such a way. At a distance of 30 meters (more or less, depending on the calculations), two hooks are securely attached. Between them, the required amount of thin wire is stretched, from which a stranded conductor will be composed. Then one end is removed from the hook and inserted into an electric drill.

At low speeds, the wire bundle twists evenly, its total length will decrease somewhat. Clean the ends of the wire (separately each core), tin and solder well. Then insulate the entire wire, preferably with a textile-based insulating material.

Core

Good performance is shown by home-made welding machines based on transformer steel cores. They are recruited from plates with a thickness of 0.35-0.55 millimeters.

It is important to choose the right size of the window in the core so that both coils fit in it, and the cross-sectional area (its thickness) is 35-50 square centimeters. Bolts are installed at the corners of the finished core, and everything is tightly tightened with nuts.

The primary winding consists of 215 turns. To be able to regulate welding current of the finished apparatus, conclusions can be drawn from winding on 165 and 190 turns.

All contacts are mounted on a plate of insulating material and signed. The scheme is as follows: the more turns of the coil, the greater the current at the output. The secondary winding consists of 70 turns.

inverter

You can assemble another welding device with your own hands - this is an inverter. It has a number of positive differences from the transformer. The very first thing that catches your eye is its light weight. Just a few kilos. You can work without removing the device from your shoulder. Then, working direct current, this allows you to create a more accurate seam, and the arc does not jump so much. Easier for beginner welders.

Parts for assembling such a device are sold in stores and on the market. You just need to know the label. The quality of the transistors requires special attention because they are in the most stressed area of ​​​​the inverter design circuit. To cool the device, forced ventilation is used in the form of cooling radiators and exhaust fans.

Thus, if you compile a catalog of home-made welding machines, you will get a long list of transformers of various designs, inverters, semi-automatic welding machines and automatic machines. Such devices allow you to work with cast iron and steel, aluminum and copper, stainless steel and thin sheet iron.

The reliability and durability of their work depends on the accuracy of calculations, the availability of materials, parts, correct assembly, as well as compliance with safety rules at all stages of the creation and operation of such devices.

Photo of a welding machine at home

No work with iron can do without a welding machine. It allows you to cut and connect metal parts of any size and thickness. A good solution is to do welding with your own hands, because good models are expensive and cheap ones are of low quality. To implement the idea self-manufacturing It is necessary for a welder to acquire special equipment that allows you to hone the quality skills of a specialist in real conditions.

Types and characteristics of the tool

After all the necessary conditions for the preparatory stage are successfully met, it becomes possible to make a model of the welding device with your own hands. Today there are many circuit diagrams, according to which the device can be manufactured. They operate in one of the following ways:

• Direct or alternating current.
• Pulse or inverter.
• Automatic or semi-automatic.

It is worth paying attention to the apparatus belonging to the transformer type. An important characteristic of this device is its operation on alternating current, which allows it to be used in domestic conditions. AC devices are capable of providing the nomenclature quality of welded joints. A unit of this type can easily find its application in everyday life. when servicing real estate located in the private sector.

In order to assemble such a device, you must have:

• About 20 meters of cable or wire of large cross section.
• High magnetic permeability metal base to be used as the core of the transformer.

The optimal core configuration has a U-shaped rod base. In theory, a core of any other configuration can easily fit, for example, a round shape taken from a stator that has become unusable. But in practice, winding the winding on such a base is much more difficult.

The cross-sectional area for a core belonging to a home-made household welding machine is 50 cm 2. This will be enough to use rods from 3 to 4 mm in diameter in the installation. The use of a larger section will only lead to an increase in the mass of the structure, and the efficiency of the apparatus will not become higher.

Manufacturing instructions

For the primary winding, it is necessary to use a copper wire with high heat resistance, since during welding it will be exposed to high temperatures. The wire used must be selected according to fiberglass or cotton insulation designed for stationary use in the high temperature zone.

For the winding of the transformer, it is not allowed to use a wire with PVC insulation, which, when heated, will instantly become unusable. In some cases, insulation for the transformer winding is made independently.

To perform this procedure, you need to take a blank made of cotton fabric or fiberglass, cut it into strips about 2 cm wide, wrap the prepared wire with them and soak the bandage with any varnish that has electrical properties. Such insulation in terms of thermal characteristics will not yield to any factory analogue.

Coils are wound according to a certain principle. First, half of the primary winding is wound, followed by half of the secondary. Then proceed to the second coil using the same technique. To improve the quality of the insulating coating between the layers of the windings, fragments of strips of cardboard, fiberglass or pressed paper are inserted.

Hardware setup

Next, you need to configure. It is produced by turning on the equipment in the network and taking voltage readings from the secondary winding. The voltage on it should be from 60 to 65 volts.

Precise adjustment of the parameters is carried out by reducing or increasing the length of the winding. To obtain a qualitative result, the voltage on the secondary winding should be adjusted to the specified parameters.

To primary winding the finished welding transformer is connected to the VRP cable or the SHRPS wire, which will be used to connect to the network. One of the outputs of the secondary winding is fed to the terminal, to which the “mass” will subsequently be connected, and the second is fed to the terminal connected to the cable. The last procedure is completed and the new welding machine is ready for operation.

Small unit production

For the manufacture of a small welding machine, an autotransformer from a Soviet-style TV is easily suitable. It can be easily used to obtain a voltaic arc. In order for everything to work out correctly, graphite electrodes are connected between the terminals of the autotransformer. This simple design allows you to perform several simple jobs using welding, such as:

• Making or repairing thermocouples.
• Warm up to maximum temperature high carbon steel products.
• Hardening of tool steel.

A home-made welding machine, created on the basis of an autotransformer, has a significant drawback. It must be used with extra precautions. Without galvanic isolation from the electrical network, it is a rather dangerous device.

The optimal parameters of an autotransformer suitable for creating a welding machine are considered to be an output voltage in the range from 40 to 50 volts and low power from 200 to 300 watts. This device is capable of delivering from 10 to 12 amperes of operating current, which will be sufficient when welding wires, thermocouples and other elements.

As electrodes for a do-it-yourself mini welding machine, you can use leads from a simple pencil. Holders for improvised electrodes can serve as terminals that are on various electrical appliances.

For welding, the holder is connected to one of the terminals of the secondary winding, and the workpiece to be welded to the other. The handle for the holder is best made from fiberglass washer or other heat-resistant material. It should be noted that the arc of such a device operates for a rather short time, preventing the autotransformer used from overheating.

The welding machine is a fairly popular device among both professionals and home craftsmen. But for domestic use, sometimes it makes no sense to buy an expensive unit, since it will be used in rare cases, for example, if you need to weld a pipe or put up a fence. Therefore, it would be wiser to make a welding machine with your own hands, investing a minimum amount of money in it.

The main part of any welder working on the principle arc welding, is a transformer. This part can be removed from an old, unnecessary household appliances and make a homemade welding machine out of it. But in most cases, the transformer needs a little refinement. There are several ways to make a welder, which can be both the simplest and more complex, requiring knowledge in radio electronics.

To make a mini welding machine, you will need a couple of transformers taken from an unnecessary microwave oven. A microwave is easy to find with friends, acquaintances, neighbors, etc. The main thing is that it has a power in the range of 650-800 W, and the transformer in it is working. If the stove has a more powerful transformer, then the device will turn out with higher current rates.

So, a transformer removed from a microwave oven has 2 windings: primary (primary) and secondary (secondary).

Resale has more turns and a smaller wire cross section. Therefore, in order for the transformer to become suitable for welding, it must be removed and replaced with a conductor with a larger cross-sectional area. To remove this winding from the transformer, it must be cut on both sides of the part with a hacksaw.

This must be done with special care so as not to accidentally touch the primary winding with a saw.

When the coil is cut, its remains will need to be removed from the magnetic circuit. This task will be much easier if you drill the windings to relieve the stress of the metal.

Do the same with the other transformer. As a result, you will get 2 parts with a primary winding of 220 V.

Important! Don't forget to remove the current shunts (shown with arrows in the photo below). This will increase the power of the device by 30 percent.

For the manufacture of the secondary, you will need to purchase 11-12 meters of wire. It must be multi-core and have cross section of at least 6 squares.

To make a welding machine, for each transformer you will need to wind 18 turns (6 rows in height and 3 layers in thickness).

Both transformers can be wound with one wire or separately. In the second case, the coils should connect in series.

The winding should be made very tight so that the wires do not hang out. Next, the primary windings need connect in parallel.

To connect the parts together, they can be screwed to a small piece of wood board.

If you measure the voltage on the secondary of the transformer, then in this case it will be equal to 31-32 V.

With such a home-made welder, metal 2 mm thick is easily welded with electrodes with a diameter of 2.5 mm.

It should be remembered that cooking with such a home-made apparatus should be done with breaks for rest, since its windings are very hot. On average, after each used electrode, the device should cool down for 20-30 minutes.

Thin metal with a unit made from a microwave will not be able to cook, as it will cut it. To adjust the current, a ballast resistor or choke can be connected to the welder. The role of a resistor can be performed by a piece of steel wire of a certain length (selected experimentally), which is connected to a low-voltage winding.

AC Welder

This is the most common type of apparatus for welding metals. It is easy to make at home, and it is unpretentious in operation. But the main disadvantage of the apparatus is large mass of step-down transformer, which is the basis of the aggregate.

For home use, it is enough that the device produces a voltage of 60 V and can provide a current of 120-160 A. Therefore, for primary, to which a 220 V household network is connected, a wire with a cross section of 3 mm 2 to 4 mm 2 is required. But the ideal option is a conductor with a cross section of 7 mm 2. With such a cross section, voltage drops and possible additional loads will not be terrible for the device. From this it follows that for the secondary you need a conductor having a diameter of 3 mm. If you take aluminum wire nickname, then the calculated cross section of copper is multiplied by a factor of 1.6. For resale a copper bus with a cross section of at least 25 mm 2 is required

It is very important that the winding conductor is covered with rag insulation, since the traditional PVC sheath will melt when heated, which can cause an interturn short circuit.

If you did not find a wire with the required cross section, then it can be make your own from several thinner conductors. But at the same time, the thickness of the wire and, accordingly, the dimensions of the unit will increase significantly.

First thing, the basis of the transformer is made - the core. It is made of metal plates (transformer steel). These plates should have a thickness of 0.35-0.55 mm. The studs connecting the plates must be well insulated from them. Before assembling the core, its dimensions are calculated, that is, the dimensions of the “window” and the cross-sectional area of ​​​​the core, the so-called “core”. To calculate the area, use the formula: S cm 2 \u003d a x b (see figure below).

But it is known from practice that if a core is made with an area of ​​​​less than 30 cm 2, then it will be difficult to obtain a high-quality seam with such an apparatus due to a lack of power reserve. Yes, and it will heat up very quickly. Therefore, the cross section of the core must be at least 50 cm 2 . Despite the fact that the mass of the unit will increase, it will become more reliable.

To assemble the core, it is better to use L-shaped plates and place them as shown in the following figure until the thickness of the part reaches the required value.

At the end of the assembly, the plates must be fastened (at the corners) with bolts, then cleaned with a file and insulated with fabric insulation.

Now we can start transformer winding.

One caveat should be taken into account: the ratio of turns on the core should be 40% to 60%. This means that on the side where the primary is located, there should be fewer turns of the secondary. Due to this, at the start of welding, the winding with more turns will be partially switched off due to the occurrence of eddy currents. This will increase the current strength, which in a positive way affect the quality of the seam.

When the winding of the transformer is completed, network cable connects to a common wire and to a branch of the 215th turn. Welding cables are connected to the secondary winding. After that, the contact welding machine is ready for operation.

DC device

To cook cast iron or stainless steel, an apparatus is required direct current. It can be made from a conventional transformer unit, if its secondary winding connect rectifier. Below is a diagram of a welding machine with a diode bridge.

Scheme of a welding machine with a diode bridge

The rectifier is assembled on D161 diodes, capable of withstanding 200A. They must be installed on radiators. Also, to equalize the current ripple, you will need 2 capacitors (C1 and C2) for 50 V and 1500 uF. This circuit also has a current regulator, the role of which is performed by the inductor L1. Welding cables are connected to contacts X5 and X4 (direct or reverse polarity), depending on the thickness of the metal to be joined.

Computer power supply inverter

It is impossible to make a welding machine from a computer power supply. But using its case and some parts, as well as the fan, is quite realistic. So, if you make an inverter with your own hands, then it can easily be placed in the PSU case from the computer. All transistors (IRG4PC50U) and diodes (KD2997A) must be installed on radiators without the use of gaskets. For cooling parts, it is desirable use a powerful fan, such as Thermaltake A2016. Despite its small size (80 x 80 mm), the cooler is capable of 4800 rpm. The fan also has a built-in speed controller. The latter are regulated using a thermocouple, which must be mounted on a radiator with installed diodes.

Advice! It is recommended to drill several additional holes in the PSU case for better ventilation and heat dissipation. The overheating protection installed on the radiators of the transistors is set to operate at a temperature of 70-72 degrees.

Below is a circuit diagram of a welding inverter (in high resolution), according to which you can make a device that fits in the PSU case.

The following photos show what components a homemade inverter welding machine consists of, and how it looks after assembly.

electric motor welder

To make a simple welding machine from the stator of an electric motor, it is necessary to select the motor itself that meets certain requirements, namely, that its power is from 7 to 15 kW.

Advice! It is best to use a 2A series motor, as it will have a large magnetic circuit window.

You can get the right stator in places where scrap metal is accepted. As a rule, it will be cleaned of wires and after a couple of blows with a sledgehammer it will split. But if the body is made of aluminum, then in order to remove the magnetic circuit from it, stator needs to be annealed.

Preparation for work

Place the stator with the hole up and place bricks under the part. Next, stack the wood inside and set it on fire. After a couple of hours of roasting, the magnetic core will easily separate from the body. If there are wires in the housing, they can also be removed from the grooves after heat treatment. As a result, you will receive a magnetic circuit cleaned of unnecessary elements.

This blank should be well saturate with oil varnish and let it dry. You can use a heat gun to speed up the process. Impregnation with varnish is done so that after removing the screeds, the package does not spill.

When the blank is completely dry, using the grinder, remove the ties located on it. If the ties are not removed, they will act as short-circuited turns and take power from the transformer, as well as cause it to heat up.

After cleaning the magnetic circuit from unnecessary parts, you will need to make two end caps(see picture below).

The material for their manufacture can be either cardboard or pressboard. You also need to make two sleeves from these materials. One will be internal, and the second - external. Next, you need:

• install both end plates on the blank;
• then insert (dress) the cylinders;
• wrap all this structure with keeper or glass tape;
• impregnate the resulting part with varnish and dry.

Transformer manufacturing

After carrying out the above steps, it will be possible to make a welding transformer from the magnetic circuit. For these purposes, you will need a wire covered with fabric or glass-enamel insulation. To wind the primary winding, you need a wire with a diameter of 2-2.5 mm. The secondary winding will require about 60 meters of copper bus (8 x 4 mm).

So, the calculations are done as follows.

1. 20 turns of wire with a diameter of at least 1.5 mm should be wound on the core, after which 12 V must be applied to it.
2. Measure the current flowing in this winding. The value should be about 2 A. If the value is greater than the required, then the number of turns must be increased, if the value is less than 2A, then reduced.
3. Count the number of turns you get and divide it by 12. As a result, you will get a value that indicates how many turns you need per 1 V of voltage.

For primary winding a conductor with a diameter of 2.36 mm is suitable, which needs to be folded in half. In principle, you can take any wire with a diameter of 1.5-2.5 mm. But first you need to calculate the cross section of the conductors in the coil. First you need to wind the primary winding (at 220 V), and then the secondary. Its wire must be insulated along its entire length.

If you make a tap in the secondary winding in the area where 13 V is obtained, and put diode bridge, then this transformer can be used instead of a battery if you want to start a car. For welding, the voltage on the secondary winding should be in the range of 60-70 V, which will allow the use of electrodes with a diameter of 3 to 5 mm.

If you have laid both windings, and there is free space left in this design, then you can add 4 turns of a copper bus bar (40 x 5 mm). In this case, you will receive a winding for spot welding, which will allow you to connect sheet metal up to 1.5 mm thick.

For case manufacturing metal is not recommended. It is better to make it from textolite or plastic. In places where the coil is attached to the body, rubber gaskets should be laid to reduce vibration and better insulation from conductive materials.

Homemade spot welding machine

The finished spot welding machine has a rather high price, which does not justify its internal “stuffing”. It is arranged very simply, and it will not be difficult to make it yourself.

To make a spot welding machine yourself, you need one transformer from a microwave oven with a power of 700-800 watts. It is necessary to remove the secondary winding from it in the manner described above, in the section where the manufacture of a microwave welding machine was considered.

The spot welding machine is made in the following way.

1. Make 2-3 turns inside the manitoduct with a cable with a conductor diameter of at least 1 cm. This will be the secondary winding, which allows you to get a current of 1000 A.
   
   
2. It is recommended to install copper lugs at the ends of the cable.
   
   
3. If you connect 220 V to the primary winding, then on the secondary winding we will get a voltage of 2 V with a current strength of about 800 A. This will be enough to melt an ordinary nail in a few seconds.
   
   

   

4. Followed by make a case for the device. Good for base wooden plank, from which several elements should be made, as shown in the following figure. The dimensions of all parts can be arbitrary and depend on the dimensions of the transformer.
   
   

   

5. To give the case a more aesthetic appearance, sharp corners can be removed with manual router with an edge moulder mounted on it.
   
   

   

6. On one part of the welding tongs, it is necessary cut a small wedge. Thanks to him, ticks will be able to rise higher.
   
   

   

7. Cut to back wall openings for the switch and mains cable.
   
   
8. When all the details are ready and sanded, they can be painted with black paint or varnished.
   
   
9. From an unnecessary microwave, you will need to disconnect the mains cable and limit switch. You will also need a metal door handle.
   
   

   

10. If you do not have a switch and a copper rod lying around at home, as well as copper clips, then these parts must be purchased.
    
    
11. From the copper wire, cut 2 small rods that will act as electrodes and fix them in the clamps.
    
    

    

12. Screw the switch to the rear wall of the device.
    
    
13. Screw the back wall and 2 posts to the base, as shown in the following photos.
    
    

    

14. Attach the transformer to the base.
    
    
15. Next, one mains wire is connected to the primary winding of the transformer. The second network wire is connected to the first terminal of the switch. Then you need to attach the wire to the second terminal of the switch and connect it to another output of the primary. But on this wire you should make a gap and install in it microwave interrupter. It will act as a welding start button. These wires must be long enough to accommodate a breaker at the end of the clamp.
16. Fasten the cover of the device with the handle installed on the racks and the rear wall.
    
    
17. Fasten the side walls of the case.
    
    
18. Now you can install the welding tongs. First, drill a hole at their ends into which the screws will be screwed.
    
    
19. Next, attach the switch to the end.
    
    
20. Insert the pliers into the housing, after placing a square bar between them for alignment. Drill holes in the pliers through the side walls and insert long nails into them to serve as axes.
    
    

    

21. Attach copper electrodes to the ends of the clamps and align them so that the ends of the rods are opposite each other.
    
    

    

22. To make the top electrode rise automatically, screw in 2 screws and fix the elastic band on them, as shown in the following photos.
    
    

    

23. Turn on the unit, connect the electrodes and press the start button. You should see an electrical discharge between the copper bars.
    
    
24. To check the operation of the unit, you can take metal washers and weld them.
    
    

    

In this case, the result was positive. Therefore, the creation of a spot welding machine can be considered completed.

From the article you will learn what it is to make them with your own hands is quite simple, if you have elementary knowledge in electrical engineering and necessary tools. As a basis for a welding machine, both a ready-made transformer and a home-made one can be taken.

Of course, such designs consume a lot of power, therefore, a strong voltage drop will be observed in the network. This may affect the functioning household electrical appliances. It is for this reason that designs based on semiconductor elements are much more effective. To put it simply, these are devices.

The simplest welding machine

So, the first thing to consider is the simplest designs that anyone can repeat. Of course, these are the devices based on transformers. The design discussed below allows you to work on voltages of 220 and 380 volts. The maximum electrode diameter used in welding is 4 mm. The thickness of the welded metal elements ranges from 1 to 20 millimeters. About that, you now know in full. And you can move from simple to complex.

Despite such excellent characteristics, the manufacture of the welding machine is made from readily available materials. You will need a three-phase step-down transformer for assembly. At the same time, its power should be about 2 kilowatts. It is also worth noting that you will not need all the windings. Therefore, in the event that one of them fails, there will be no problems with further design.

Alteration of the transformer

The bottom line is that you only need to make changes in the secondary winding. To facilitate the task, the article below shows a diagram of the welding machine, its connection to the network is also described.

So, the primary winding does not need to be touched, it has all the characteristics necessary for operation from a 220 volt AC mains. There is no need to disassemble the core, it is enough to disassemble the secondary winding directly on it, and wind a new one instead.

The transformer you have to choose has several windings. Three primary, the same number of secondary. But there are also medium windings. There are also three of them. It is instead of the middle one that it is necessary to wind the same wire that was used to make the primary one. Moreover, it is necessary to make taps from every thirtieth turn. About 300 turns in total should have each winding. Thanks to correct winding wires can increase the power of the welding machine.

The secondary winding is wound on both extreme coils. It is difficult to specify the exact number of turns, since the more, the better. The wire is used with a cross section of 6-8 square millimeters. Together with it, a thin wire is wound at the same time. As power cable you need to use stranded in reliable insulation. That's how they do it by hand.

If we analyze all the structures made using this technology, it turns out that the approximate amount of wire is about 25 meters. If there is no wire with a large cross section, you can use a cable with an area of ​​3-4 square millimeter. But in this case, it must be folded in half when winding.

Transformer connection

The design has a simple welding machine. A semi-automatic device can be made on its basis if one more winding is made to power the electric drive for supplying electrodes. Please note that the output of the transformer will be very high current. Therefore, all switching connectors must be made as durable as possible.

To make terminals for connecting to the secondary winding terminals, you will need copper tube. It should have a diameter of 10 millimeters and a length of 3-4 cm. It needs to be riveted from one end. You should get a plate in which you need to make a hole. Its diameter should be about one centimeter. Wires are inserted from the other end. Regardless of whether the welding machine is DC or AC, switching is made as rigid and reliable as possible.

It is desirable to clean them perfectly, if necessary, treat them in acid and neutralize it. To improve contact, the second edge of the tube should be slightly flattened with a hammer. The conclusions of the primary winding are best attached to the textolite board. Its thickness should be about three millimeters, it can be more. It is rigidly attached to the transformer. In addition, 10 holes need to be made in this board, each with a diameter of about 6 millimeters. Look at the scheme of the welding machine, how it is connected to the 220 and 380 Volt network.

They need to install screws, nuts and washers. The conclusions of all primary windings are connected to them. In the event that welding is required to work from a 220-volt household network, the extreme windings of the transformer are connected in parallel. The middle winding is connected in series with them. Welding will work ideally when powered by 380 volts.

To connect the primary windings to the mains, you need to use a different scheme. Both extreme windings are connected in series. Only after that, the middle winding is switched on in series with them. The reason for this lies in the following: the middle winding is additional; with its help, the voltage and current in the secondary circuit are reduced. Thanks to this, welding machines made by their own hands according to the above technology work in normal mode.

Manufacture of the electrode holder

Of course, an integral part of any welding machine is the electrode holder. There is no need to buy ready-made, if you can make it from improvised materials. You need a three-quarter pipe, its total length should be about 25 centimeters. At both ends, it is necessary to make small notches, about 1/2 of the diameter. With such a holder, the welding machine will work normally. There is a separate requirement for plastic structural elements - they must be located as far as possible from the transformer and holder.

They need to be done three to four centimeters from the edge. Then take a piece of steel wire with a diameter of 6 millimeters, weld it to the pipe opposite the larger recess. On the other hand, it is necessary to drill a hole, attach a wire to it, which will be connected to the secondary winding.

Network connection

It is worth noting that you need to connect the welding machine in accordance with all the rules. First, you need to use a knife switch, with which you can easily disconnect the device from the network. Please note that do-it-yourself welding machines should not be inferior in safety to analogues manufactured by the industry. Secondly, the cross section of the wires for connecting to the network must be at least one and a half square millimeters. The current consumption of the primary winding is a maximum of 25 amperes. In this case, the current can be changed in the range of 60..120 amperes. Please note that this design is relatively simple, so it is only suitable for domestic use.

Spot welding machine

A spot type welding machine will also be useful. The designs of such devices are no less simple than the previous ones. However, the output current is very large. But it is possible to produce resistance welding of metals up to three millimeters thick. In most designs there is no adjustment of the output current. But you can do it if you wish. True, the whole homemade work becomes more complicated. The need to regulate the output current is eliminated, since the welding process can be controlled visually. Of course, inverter welding machines will be much more efficient. But point ones can do things that no other design can do.

For manufacturing, you will need a transformer with a power of about 1 kilowatt. The primary winding remains unchanged. Only the secondary will need to be redone. And if a transformer from a household microwave oven is used, then you need to knock out the secondary winding, instead winding several turns of large-section wire. If possible, it is better to use a copper bus. The output should be about five volts, but this will be enough for the full operation of the device.

Electrode holder design

Here it is slightly different from the one discussed above. For the manufacture you will need small duralumin blanks. Suitable rods with a diameter of 3 centimeters. The lower one must be motionless, completely isolated from the contacts. As an insulating material, you can use textolite washers, as well as varnished cloth. Any, even the simplest spot welding machine needs a reliable electrode holder, so pay maximum attention to its design.

The electrodes are made of copper, their diameter is 10-12 millimeters. They are firmly fixed in the holder with rectangular brass inserts. The initial position of the electrode holder - its halves are divorced. Springs can be used to give elasticity. Perfect for old cots.

Resistance welding work

It is necessary to connect such welding to electrical network with help circuit breaker. He must have rated current 20 amps. Pay attention to the fact that at the input (where you have the counter) the machine must be either the same in terms of parameters or larger. To turn on the transformer, a simple magnetic starter is used. The operation of a contact-type welding machine is somewhat different from the one discussed above. And now you will find out these features.

To turn on the magnetic starter, it is necessary to provide a special pedal that you will press with your foot to generate current in the secondary circuit. Please note that resistance welding is switched on and off only if the electrodes are fully brought together. If you neglect this rule, then a lot of sparks will appear, as a result, this will lead to burning of the electrodes, their failure. Try to pay attention to the temperature of the welding machine as often as possible. Take small breaks from time to time. Do not allow the unit to overheat.

inverter welding machine

It is the most modern, but more difficult to design. It also uses semiconductor transistors with high power. Perhaps these are the most expensive and scarce parts. First of all, the power supply is made. It is pulsed, so it is necessary to make a special transformer. And now in more detail about what such a welding machine consists of. See the specifications of its components below.

Of course, the transformer used in the inverter is much smaller than those discussed above. You will also need to make a throttle. So, you should get a ferrite core, a frame for making a transformer, copper tires, special brackets to fix the two halves of the ferrite core, electrical tape. The latter must be chosen based on the data of its thermal stability. Stick to these tips when making inverter welders.

winding transformer

The transformer is wound over the entire width of the frame. Only under this condition will it be able to withstand any voltage drop. For winding, either a copper bus or wires assembled in a bundle is used. Please note that aluminum wire cannot be used! It can't handle that much density. electric current which is present in the inverter. Such a welding machine for giving is able to help you out, and its weight is extremely small. The coils are wound as tightly as possible. The secondary winding is two wires with a thickness of about two millimeters, twisted together.

They should be isolated from each other as much as possible. If you have large stocks from old TVs, you can use them in the design. It takes 5 pieces, and you need to make one common magnetic circuit out of them. In order for the device to work with maximum efficiency, you need to pay attention to every little thing. In particular, the thickness of the wire of the output winding of the transformer affects its continuity.

Inverter design

To make a welding machine 200, you need to pay maximum attention to all the little things. In particular, power transistors must be mounted on a heatsink. Moreover, the use of thermal paste is welcomed to transfer heat from the transistor to the radiator. And it is recommended to change it from time to time, as it tends to dry out. In this case, heat transfer worsens, there is a possibility that semiconductors will fail. In addition, you need to do forced cooling. For this purpose, exhaust coolers are used. Diodes used to rectify alternating current must be mounted on an aluminum plate. Its thickness should be 6 millimeters.

The connection of the terminals is carried out using an uninsulated wire. Its cross section should be 4 mm. Please note that there is a maximum distance between the connection wires. They should not touch each other, no matter what impact the body of the welding machine experiences. The throttle must be fixed to the base of the welding machine with a metal plate.

Moreover, the latter should completely repeat the shape of the throttle itself. To reduce vibration, it is necessary to install a rubber seal between the housing and the throttle. Power wires inside the device are bred in different sides. Otherwise, there is a possibility that short circuit. It is necessary to install the fan in such a way that it blows all the radiators at the same time. Otherwise, if you cannot use one fan, you will have to install several.

But it is better to fully calculate in advance the installation location of all elements of the system. Please note that the secondary winding must be cooled as efficiently as possible. As you can see, not only radiators need effective airflow. On this basis, it is possible to make an argon welding machine at no cost. But its design will require the use of other materials.

Conclusion

Now you know how to make several types of welding machines. If you have skills in the design of electronic equipment, then it is better, of course, to stop at an inverter welding machine. You will spend time, but at the end you will get an excellent device that is not inferior even to expensive Japanese counterparts. Moreover, its production will cost mere pennies.

But if there is a need to make a welding machine, as they say, on hastily, then it will be easier to connect two transformers from microwave ovens with modified secondary windings. Subsequently, the entire unit can be improved by adding an electric drive for supplying electrodes to it. You can also install a cylinder filled with carbon dioxide in order to weld metals in its environment.

In the arsenal home master there are many tools for all occasions.

The welding machine is an indispensable device for real craftsmen. It can be bought in stores. However, it is much more interesting and cheaper to assemble with your own hands.

Some also have a welding machine, which every craftsman dreams of.

Today it can be purchased in specialized stores. There are many models. Various accessories for the device are sold expendable materials. Is it possible to make a welding machine with your own hands? The answer is simple: it is possible and even necessary!

Types of welding machines

All devices for welding work are divided into gas and electric. Gas installations not quite suitable for home use. They require special treatment, as they are equipped with explosive gas cylinders. Therefore, we should only talk about electrical devices. They are also different:

The welding inventory is economical and ideal for home use.

1. Generators. These installations have their own current generator. Differ in very big weight and the bulky sizes. Not suitable for home assembly and use.
2. Transformers. Such devices can be powered by 220 or 380 volts. They are very popular, especially semi-automatic.
3. Inverters. Very economical fixtures, ideal for the home. Differ in small weight, but rather difficult electronic scheme.
4. Rectifiers. Easy to make and use. Even novice welders can make quality seams. Ideal for DIY assembly.

How to start assembling an inverter apparatus?

To assemble the inverter, you need to select a circuit that will provide the necessary operating parameters for the device. It is recommended to use Soviet-made parts. This is especially true for diodes, capacitors, transistors, resistors, chokes, thyristors and finished transformers. The equipment assembled on these parts does not require complex adjustment. All parts are very compactly located on the board. For the manufacture of the device with your own hands, you can select the following options:

1. The welding machine must work with electrodes up to 4-5 mm in diameter.
2. The value of the operating current is not more than 250 A.
3. Source of power - household network voltage 220 V.
4. Welding current adjustment within 30-220 A.

The welding machine consists of several blocks: a power supply, a rectifier and an inverter.
You can start making an inverter-type welding machine with your own hands by winding the transformer in this order:

To assemble the inventory, you will need a ferrite core.

1. You need to take a ferrite core Ш8х8. You can use W7x7.
2. Primary winding No. 1 consists of 100 turns wound with wire of the PEV 0.3 brand.
3. Secondary winding No. 2 is wound with a wire with a cross section of 1 mm. The number of turns is 15.
4. Winding No. 3 - 15 turns of PEV wire 0.2 mm.
5. Windings No. 4 and No. 5 consist of 20 turns of wire with a cross section of 0.35 mm.
6. To cool the transformer, you can use a 220 V, 0.13 A fan. These parameters correspond to a fan from a Pentium 4 computer.

In order for the transistor switches to work smoothly, they need to be energized after the rectifier and smoothing capacitors. The rectifier unit is assembled according to a simple scheme on the board. All nodes of the welding machine are fixed in the body. Well, if the master’s household has a suitable case from a radio device, then you won’t have to make it from improvised materials.

An LED indicator is placed on the front side of the case, which, with its glow, notifies you that the device is connected to the network. Here you can install an additional switch of any type and a protective fuse. The fuse can be installed on the rear wall, as well as in the case itself. It depends on its design and dimensions. Variable resistance, with which the operating current will be adjusted, is also located on the front side of the case.

If a electrical circuits assembled correctly, everything is checked with a tester or other device, you can test the device.

How to assemble a transformer device?

The process of assembling a transformer welding apparatus is somewhat different from the previous version. He works on alternating current. For DC welding, a simple attachment is assembled to it. To assemble the device with your own hands, you need to get transformer iron for the core and several tens of meters of a thick copper bus or just a thick wire. You can look for these things at the collection points of non-ferrous and ferrous metal, with friends and acquaintances. It is recommended to make the core U-shaped, but it is also possible to make it round, toroidal. Some craftsmen successfully use the stator of a burned-out electric motor as a core. For a U-shaped core, the assembly order can be as follows:

To perform the primary winding, a winding wire is required.

1. Dial the core of transformer iron to its optimal cross section of about 55 square centimeters. You can do more, but the device will be heavy. With a cross section of less than 30 cm², the device may lose some of its qualities.
2. For the primary winding, a special winding wire with a cross section of 5-7 mm² is ideal. It is made of copper, has heat-resistant fiberglass or cotton insulation. This is very important, since during operation the winding can heat up to temperatures above 100 degrees. The cross section of the wire is usually square or rectangular. It is not always possible to find such a wire. You can replace it with an ordinary wire of the same cross section and modify it: remove the insulation, wrap the wire with strips of fiberglass, soak it thoroughly with a special electrical varnish and dry it. The primary winding consists of 200-230 turns.
3. For the secondary winding, you can first wind 50-60 turns. You don't need to cut the wire. It is necessary to turn on the primary winding in the network. Find a place on the wires of the secondary winding where the voltage will be equal to 60-65 V. In order to find this point, you have to unwind or wind additional turns. You can wind aluminum wire, increasing the cross section by 1.7 times.
4. The simplest transformer is assembled. It remains to place it in a suitable case.
5. For the conclusions of the secondary winding, terminals are made of copper. A tube with a diameter of about 10 mm and a length of 3-4 cm is taken. Its end is riveted, and a hole is drilled in it, the diameter of which is 10 mm. At the other end of the tube, you need to insert the end of the wire, cleaned of insulation, and crimp it with light blows of the same hammer. To enhance the contact of the wire with the tube-terminal, notches can be applied to it with a core. Homemade terminals are screwed to the body with M10 bolts and nuts. It is advisable to select copper parts. It is possible, when winding the secondary winding, to make taps every 5-10 turns of wire. These taps will allow you to change the voltage on the electrode in steps.
6. It remains to make an electrode holder. It can be made from a pipe with a diameter of about 18-20 mm. Its total length is about 25 cm. At the ends, 3-4 cm from the end, notches are cut to about half the diameter. The electrode is inserted into the recess and pressed by a spring from a welded piece of steel wire with a diameter of 6 mm. The same wire from which the secondary winding is made is fastened to the other end with a screw and an M8 nut. A rubber tube of suitable inner diameter is put on the holder. It is recommended to connect the device to the home network using a switch and wires with a cross section of 1.5 mm² or more. The current in the primary winding usually does not exceed 25 A. In the secondary winding, it can be from 60 to 120 A. When working, it is recommended to take a break after 10-15 electrodes with a diameter of 3 mm so that the transformer cools down. With thinner electrodes, this can be omitted. In cutting mode, breaks should be taken more frequently.