How to choose a welding machine for home and garden – expert reviews

Sooner or later, each of us faces the need to weld two dissimilar metals. You can entrust this process to professionals who provide such services, or you can buy a welding machine and do all the necessary work yourself. There are a great many characteristics that you should pay attention to when choosing a welding machine – here is the power source, the principle of operation of the converter, input and output voltage, as well as many other features, and all of them need to be given close attention before buying. However, first things first.

The best manufacturers of welding machines – which company to choose

Regardless of whether you use a welding machine on a daily basis or the need for it arises from time to time, preference should be given to products of well-known manufacturers, who are a kind of trendsetters in this market:

1. Daewoo

2. Aurora

3. DeWatt

4. Hitachi

5. Bosch

6. Fronius

The products of the above-described concerns are used by a great many people around the world, they are known and appreciated, they are trusted by welding professionals. By choosing a specific model from the range of these manufacturers, as well as having studied the reviews of buyers who have worked with this or that welding machine, you will have at your disposal a proven device that will conscientiously perform its own characteristics for a long time.

The principle of operation and the device of the welding machine

Despite the differences in appearance and in their own characteristics, the principle of operation of welding machines is almost always the same. Its active element is an electric arc with a temperature of more than five thousand degrees. It arises as a result of the interaction of the welding electrode and the surfaces to be welded, as a result of which the edges are melted and a new strong crystal lattice of metal is created.

In order to weld two metals, a ground (negative wire) is connected to them. The positive wire is connected to the electrode holder, as a result of which an electric arc inevitably occurs during the welding process. By melting both metal surfaces and adding special welding additives formed from the melting of the electrode, the welder makes a new, neat and durable metal seam.

Any welding machine consists of the following main components:

1. Powerful double-winding transformer;

2. Diode bridge and a set of chokes, capacitors and other structural elements;

3. Current and voltage control console;

4. Connecting wires;

5. Special clamps for fixing the positive and negative wires;

In order to obtain a high-quality seam, special requirements are imposed on the current passing during welding. First, it must have a high frequency, power and low voltage. For this purpose, a transformer is used that converts the incoming alternating current and corrects its parameters until such time as they become suitable for operation.

Types of welding machines

Welding transformers

Devices, the type of which is entirely consistent with the above. They are suitable for welding a wide variety of steel types and allow you to obtain a high-quality and durable seam. Devices of the transformer type are among the cheapest, a similar principle of operation can be found both among portable models intended for domestic use and among professional industrial models. The latter are distinguished by their significant dimensions and weight.

Advantages

• Low price;

• A wide variety of models to suit any budget;

• They give a high-quality and durable seam;

• Allows you to weld steel with any characteristics;

disadvantages

• Noisy work;

• Insufficient quality welding of cast iron and alloy steel;

Welding inverters

Structurally, these devices are similar to their transformer counterparts, however, they contain additional elements that can significantly improve their characteristics. First of all, we are talking about a diode bridge, which is installed at the output from the secondary winding of the transformer and serves to rectify the electric current and 'clean it'. Welding inverters can easily cope with work of any complexity, including quite jewelry, like creating one-piece plumbing systems. In addition, the high frequency output current allows you to work not only with iron and steel, but also with cast iron, ensuring decent welding quality.

Advantages

• Compact size and light weight;

• Power source – household network 220V;

• Allows you to adjust the output current to any frequency;

• Allows you to achieve the highest quality and uniform seam;

• Versatile;

disadvantages

• High price;

• Expensive repairs in case of breakdown;

• Complex design that increases the likelihood of device failure;

Semi-automatic welding machines

The device of these devices includes all the components of the above classes, due to which the output current is 'clean', has a minimum of interference, amperage and low voltage sufficient for comfortable operation. The difference here lies in the way the welding material is fed and the gas cloud is created. The electrode here is in the form of a thin rolled wire fed continuously using a special device, so that the welder can make a weld of almost any length. The gas required for welding is supplied through a special channel through a nozzle located next to the electrode.

Advantages

• Versatility – semi-automatic machines allow you to cook both rough metals and work with thin body parts of cars;

• The welds obtained are easy to process;

• Complete absence of slags during the execution of work;

• The possibility of obtaining a seam of any length;

• High quality welded seam;

disadvantages

• Bulky;

• High cost of welding wires

• Expensive enough;

Welding machine selection parameters

Power supply

According to this parameter, all welding machines can be divided into two conventional categories – household and industrial. The former are designed to operate from a 220V network, the latter are three-phase models operating from a voltage of 380 volts. Of course, you will not be able to connect a three-phase device to a regular household outlet.

Another parameter that you should pay attention to is the operating voltage range, in which the uninterrupted operation of the device is guaranteed. If there is a 230-240V number on the package, it means that the device shows its characteristics only at a stable voltage. Voltage surges and dips will affect its performance. And on the contrary, the 110-240V indicator not only means that the device can work in both American and European networks, but also that it is not afraid of strong voltage drops.

Working current

The parameter that has the most direct impact on the quality of the resulting seam. The dependence here is as follows: the thicker the metals being welded, the more current must be used to obtain a high-quality seam. In order to get at your disposal a universal device that allows you to weld both thin sheets of iron and thick corners, pipes and channels, you need to pay attention to the device, whose operating current range starts from 10-15 Amperes and ends at around 250-300 Ampere, and also has a step-by-step adjustment mechanism.

Power characteristics of the device

The declared power is a parameter that directly affects the ability to operate a particular device in certain conditions. Currently on sale you can find devices whose power varies from 2 to 10-12 kW. One should not think that the higher, the better: a knowingly powerful welding machine, when working in old rooms, can provoke a constant operation of protective equipment in the distribution board of the room, thereby preventing work from being done. In this case, it is required to start up obviously less powerful welding machines, the power characteristics of which do not exceed the maximum that the protective equipment can withstand.

Diameter of the used electrode

The dependence here is similar to the one described above for the current. The thicker the metal, the larger the electrode diameter is required in order to weld the seam efficiently. It is by this parameter that one can indirectly judge by the current characteristics of this or that welding machine, even without knowing its specific parameters. Here you can start from what kind of metal you have to work with – the thinner it is, the thinner the electrodes will have to be used.

Output current characteristics

The secondary winding of a welding transformer is capable of generating several different types of current, which directly affects the performance and functionality of the device:

1. Transformer type welding machines are capable of generating alternating current suitable for welding any metal object;

2. Welding inverters also produce alternating current, but after passing through the diode bridge and filtering, it becomes cleaner, and its frequency increases. This makes it possible to weld fairly thick metals, and also has a positive effect on the quality of the weld;

3. Devices generating direct current or combined options are the most functional, allowing you to cook not only cast iron and alloy steel, but also stainless steel, without deteriorating its operational properties;

Duty cycle characteristics

A parameter that displays the ability of a particular welding machine to operate at maximum power. Due to technical features, the welding machine tends to heat up, due to which its characteristics deteriorate significantly. The parameter, referred to as the duty cycle, displays the amount of time that the welding machine can operate in full cycle mode and at maximum power. For example, if this parameter is declared by the manufacturer as 70%, this means that out of ten minutes of continuous operation, the welding machine is capable of operating at maximum power seven. The remaining time the power is increased mechanically in order to prevent overheating and damage to the device.

Which welding machine to choose

1. For those looking for a welder for plumbing operations and welding water and sewer pipes, it is best to pay attention to a welding inverter capable of delivering a current of up to 200 Amperes and operating in a current range of 150-250 Volts.

2. For those who select welding for car repairs, it is best to buy a semiautomatic welding machine that allows you to work with a wire 0.8-1 mm thick, delivering a current of up to 400 Amperes and operating in the voltage range from 150 to 250 Volts. Cyclicity of work also plays an important role – it should reach 90-100 percent so that the device does not switch off deliberately during the seam;

3. For normal work with metals in a personal plot or a summer residence, an inexpensive transformer device operating from a 220V household network and capable of generating a current of up to 200-250 Amperes is quite enough;

4. Thick-walled devices, boilers and heat exchangers require the welder to use powerful inverter welding machines operating from a single-phase or three-phase network (it all depends on the specific connection point and power source), capable of generating a current of up to 400A. The power of the device must also be appropriate – almost all such models reach 7-8 kW.

How much does the welding machine cost

1. A high-quality inverter can be bought at a price of 6 to 15 thousand rubles. Powerful models designed to work with thick metal are more expensive – their cost can reach 40-50 thousand rubles;

2. Semi-automatic welding machines are much more expensive. Those who plan to repair a car need to have in their pockets from 16 to 150 thousand rubles for a high-quality semiautomatic device;

3. Compact transformers for household use, which can be called universal, are quite affordable for every buyer – the price for the most expensive devices does not exceed 5 thousand rubles;

In the following articles, our experts will tell you how to choose a saw blade, the secrets of choosing a mask for welding and the features of choosing a laser level.

Video for choosing a welding machine

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Attention! This material is the subjective opinion of the authors of the project and is not a purchase guide.