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Building a house or renovating it often requires welding. Every time to seek help from professionals is long and expensive. Moreover, most of the work does not require any prohibitively high qualifications. However, you have to pay decent money. If you are planning a construction or repair, you have a large dacha or house, it will be cheaper for you to do all (or almost all) welding work yourself. And we will tell you how to choose a welding machine for home and garden.
Electric welding machine for home and garden, types, advantages and disadvantages
Both at home and at work, electric welders are most often used. For the most part, household models operate on a 220 V network, but you can also find devices that are powered by a three-phase 380 V network. Some of them cook on direct current, some on alternating current.
Transformer welding machines
Welding transformers produce alternating current at the output. Their design is simple and reliable: two step-down transformers with the ability to adjust the output current. The adjustment is not very precise and its range is small. And this is one of the drawbacks. This unit rarely breaks down, but it weighs a lot: even a household model that is not the most powerful will drag on a couple of tens of kilograms. Industrial models can weigh hundreds of kilograms or even more.
About two decades ago, electric welding was only on “trances”. Today, this is far from the case: sources of direct welding current have become more widespread. And all because of the shortcomings of the transformer welding machine. The current it gives out is alternating, its polarity is constantly changing. When welding, this is expressed in the fact that the arc “jumps”, which causes a large number of sparks. At the same time, the arc is difficult to control, obtaining a high-quality seam is possible only with a highly qualified welder. But even under this condition, they are used only for welding ferrous metal: the adjustment possibilities are limited, fine tuning is almost impossible in general, which limits the scope of their use.
Another significant drawback: during operation, especially when the arc is ignited, the voltage in the network sags significantly. Such jumps do not like modern electronics, which we have more than enough both in the house and in the country. Therefore, for home use, transformer welding machines are bought very rarely. Even though they are reliable and inexpensive. If someone has them, they stand in the garage or shed as a backup option “just in case.”
Welding rectifiers
In fact, these are the same welding transformers, but they have a rectifier unit at the output. They are sometimes called DC welding transformers. They give out direct current, which is why the arc is more stable, it is easier to work, but experience is still needed, albeit to a lesser extent than on transformers. Their disadvantage: power loss on the rectifier, but this is compensated by a constant arc.
The design is reliable, there is nothing special to break: a step-down transformer, a block of rectifiers and adjustments. These are all components of the welding rectifier. The price is a little higher than for transformers. But this type of welder is not popular today. The disadvantages are almost the same: a large mass, power surges during operation. Connecting the welding machine to the household network and working with it will cause voltage drops and, consequently, dissatisfaction with the neighbors.
Welding inverters
Once they hit the market, they were expensive. With the development of technology and the advent of a new element base (IGBT transistors), their characteristics have become better, their weight is less, and the price is lower. Modern household welding inverters can weigh from 3 kg and give out a current of 160-180 amperes, which is enough to work with an electrode of 3-4 mm. Their cost is about 3-6 thousand rubles. Not very much, given the prices for the services of welders.
They give out a stable arc, it is easy to control it. A non-professional can also get a good seam, and even with little practice. The design is such that it allows you to adjust the welding current and voltage in a wide range. This allows you to use the same machine for welding different metals, different thicknesses.
Another important advantage is that inverter welding does not “set” the network. Almost no effect on her. The only condition: the socket for the welding machine must be grounded. The protection class of these units is IP21, which means that they are grounded through the mains. Therefore, the connection of the inverter welding machine to the household network is only through a socket with grounding.
If you need a mobile, lightweight welding machine for home and garden, choose it from welding inverters. It’s easy to learn how to cook with it. You will not become a super-welder soon, but you will be able to do almost all the work around the house or at a construction site yourself after a short period of time.
Welding machine for home and garden: transformer or inverter?
Almost no one has questions regarding which welding machine is better – an inverter or a transformer. Even in a plant where there are good transformers, when inverters appear, they are idle. And for the house there are no questions: inverters are definitely better. And that’s why:
- better weld quality
- dimensions and weight are much less,
- more adjustments, more precise settings;
- it does not affect the network, it “pulls” little electricity.
Welding machine for manual electric arc welding can weld all kinds of steel
The only fly in the ointment is the price: it is higher than for transformers. But there are good brands that cost a little. For example, Resanta inverters. For professional use, they are hardly suitable, but as a welding machine for the home or for giving, they showed themselves very well. Prices for household modifications (140-160 Amperes) $ 110-130.
Welding machines (semi-automatic)
These are more complex and much more productive devices. It is based on one of the welding current sources described above, plus a welding wire feeder, torch and control unit. Welding on such devices is carried out in a shielding gas environment, metals are connected using a special soldering wire. This allows you to easily connect parts made of thin metal, as well as weld non-ferrous metals. For the home, such equipment is unlikely to be in demand, and they are often used in car repair shops for body repairs.
Semi-automatic welding machines can work in two MIG / MAG modes. MIG – welding with the supply of inert gases. It is used when joining stainless steel to preserve alloying metals in the composition of steel. MAG mode – when active gases are supplied to the melting zone, protecting the metal from interaction with atmospheric oxygen. Some models can also work in MMA welding mode – manual arc. This mode in semi-automatic machines is convenient when connecting thin metals. When welding thick parts, this equipment shows low productivity, so for these cases it is more profitable to take devices for manual electric arc welding.
It is not difficult to work with them: there is an automation unit that controls the process. The seam is beautiful and even, there are no problems with the occurrence of an arc at all. Even if very thin sheets of metal (0,5-0,8 mm) are welded, they are not “led” and the seam does not pull. For these purposes, they are ideal.
How to choose an electric welding machine
If you have decided on the type of welding machine (transformer, rectifier, inverter, automatic machine or generator), you must choose a model. There are several key parameters that will make this process easier:
- Supply voltage: 220 V or 380 V. For everyday life, welders operating from 220 V are usually taken. All types of welding machines, except for inverters, are quite demanding on its characteristics. It is only inverters that can operate in the range of 180-250 V without problems. For the rest, protection is triggered when it rises (they turn off), and when it decreases, the parameters drop dramatically. Three-phase devices for 380 V, as a rule, are more powerful and reliable, but they are also more expensive (minimum – about 20-30 thousand rubles). They are often purchased for production, for large service stations. For welding “for yourself” with your own hands, the power of these units is excessive.
- output current. If you choose a welding machine for home and summer cottages, you will use it periodically, for most work a current of 160-180 Amperes is enough (inverters on this current can work with 3-4 mm electrodes without problems). If you intend to cook thick metal, you do not need more than 190-250 amperes. Industrial models can deliver up to 500 A.
What current should be boiled with different electrodes (general recommendations, select exactly by experience) - Open circuit voltage. Measured on the device without load. It can be from 45 V to 80-95 V. The ease of ignition of the arc depends on this parameter. The higher the open circuit voltage, the easier it is to start welding. Also, the increased characteristics guarantee a more stable arc, which makes welding easier. This parameter is taken into account when choosing the type of electrodes: for some, a small voltage is sufficient for ignition (riutil coating), for others, higher values uXNUMXbuXNUMXbare needed (basic coating).
| Thickness of metal, mm | Electrode diameter, mm |
|---|---|
| 1,2 – 2,0 mm | 1,5 mm |
| 1,5 – 3,0 mm | 2,0 mm |
| 1,5 – 5,0 mm | 2,5 mm |
| 2,0 – 12,0 mm | 3,0 mm |
| 4,0 – 20 mm | 4,0 mm |
| 10 – 40 mm | 5,0 mm |
- The maximum diameter of the electrodes that the unit can work with. This indicator, in addition to the selection of electrodes, also affects the thickness of the metal with which the device can work.
A few general tips for choosing a welding machine. To decide which welding machine is best for your home, start from the tasks that you will need to solve. A transformer is enough for welding ferrous metal. If you need to weld structural or low-alloy steel, you need an inverter. For welding thin or non-ferrous metals – semi-automatic.
Often size is the deciding factor. If you need a portable, portable and compact welding machine, this is an inverter powered by 220 V. It has a very small size and weight. It is easy to carry even just on the shoulder, hanging on the belt. At the same time, it works with a wide range of materials, making it possible to obtain a good seam.
If your power supply is far from ideal, then an inverter welder is also suitable for you: they are not afraid of voltage drops and work even when it drops to 180 V. Some models designed specifically for low voltage work at all at 160 V.
The same devices are also recommended for novice welders: some of them have several useful features that greatly facilitate the work of a beginner in welding:
- Hot Start mode – “hot start” – facilitates the ignition of the arc. At the moment of the start of welding, an additional current pulse is issued to facilitate ignition;
- Anti-Stick – “against sticking.” At the beginning of work, it is difficult for a beginner to choose the right welding parameters. As a result, the electrode “sticks” to the workpiece. When working with transformers and rectifiers, it is not easy to tear it off later. In inverters, the current is automatically reduced, and the electrode can be torn off without any problems.
- Arc Force – increased power. With the rapid approach of the electrode, the current strength increases, preventing the electrode from sticking.
If you are new to welding and decide which is better – an inverter or a transformer – the choice is simple for you: definitely an inverter (read how to choose an inverter welding machine). It has only one drawback: after you learn how to work on an inverter, you will not be able to work on a transformer without retraining. Among other disadvantages: he does not like dust, especially metal. Therefore, next to him it is better not to clean metals and not work with a grinder or grinders. Well, like any electrical equipment, they do not like humidity and are afraid of condensate.
Welding generators
This is a rather complex equipment that combines a generator (gasoline or diesel) and a welding current source. Moreover, welding can be from both direct and alternating current. The equipment is already quite expensive, but it is the best option for those villages or construction sites where there is no electricity yet, or it is very unstable. If your holiday village is not yet electrified, you need a similar unit.
Can conventional electric welding machines be powered by a generator? They can, but if household appliances or other electrics in the network are also powered from it, then they will have to be turned off for the duration of operation: the voltage will “jump”, because of which they can break. There is one more point: welding machines require a generator of a simpler design (they are not so demanding on the characteristics of the power source). Because his scheme is much simpler. As a result, a welding generator costs less than a pair of electric welding + generator.
If you do not have electricity, or there are significant interruptions with it, it is more profitable to buy not a welding machine for your home and / or cottage, but a welding generator.
The choice here begins with the type of generator: gasoline or diesel. Then choose the type of welding current source: transformer, rectifier or inverter. Then there are the usual electric welding parameters described above.
Welding machine for aluminum
A feature of aluminum welding is a low melting point, and, as a rule, a small thickness of the metal. Therefore, ordinary manual welding is not entirely suitable here: experience is required, and not everyone has it. We need welding in a shielding gas environment (semi-automatic in MIG mode) or an argon-arc welding machine (TIG welding). The process of welding aluminum by argon arc welding, see the video.
There are also universal multifunctional welding machines. One such unit can operate in three to five types of welding. But the cost of such wagons is already in the hundreds of thousands. For the home, they are absolutely useless. These are already professional welding machines, and for a wide range of jobs. For example, Multiplaz 4000 operates in the following modes:
- manual electrode welding (MMA)
- argon-arc welding with non-consumable electrode (TIG)
Both of these modes can take place in a shielding gas environment in alternating (AC), direct (DC) or pulsed (pulsating) (PULSE) current modes. He has not just a lot of adjustments, but a lot, the range of parameters is very wide. In addition to all “standard” types of steel, it can cook aluminum, even without pre-treatment, thin stainless steel, titanium. The seam will be very high quality. But whether you need such an installation at home or in the country is a question. Unless you then plan to open a production or earn money by welding.