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An apartment, and especially a private house, needs regular maintenance and repair work. A home handyman has to be a generalist, capable of performing many different tasks. Therefore, masters want to master as many technologies as possible.

One of the most in-demand skills is the ability to perform welding work. Practice shows that electric welding is best suited for beginners - the technology is simple and accessible to anyone who wants to learn how to use it. Before you start mastering the method, you should familiarize yourself with the theoretical aspects of the issue, don’t you agree?

All the necessary information is described in detail in our article. We described the principle of operation of electric welding and indicated which device is best to choose for working at home. In addition, the article provides a step-by-step technology for welding parts, methods for making seams, and also lists possible defects in joints.

Electric is one of the welding methods when an electric arc is used to heat and subsequently melt metals. The temperature of the latter reaches 7000°C, which is much higher than the melting point of most metals.

The electric welding process proceeds as follows. To form and maintain an electric arc, current is supplied from the welding device to the electrode.

During the welding process, the base metal and the metal core of the electrode are melted and mixed, forming a strong and unbreakable weld (+)

When the electrode rod touches the surface to be welded, welding current flows. Under its influence and the influence of the electric arc, the electrode and the metal edges of the elements being welded begin to melt. From the melt, as welders say, a weld pool is formed, in which the molten electrode is mixed with the base metal.

Molten slag floats to the surface of the bath, which forms a protective film. After the arc is turned off, the metal gradually cools, forming a seam covered with scale. After the material has completely cooled, it is cleaned off.

Non-consumable and consumable electrodes can be used for welding. In the first case, filler wire is introduced into the melt to form a welding seam, in the second this is not required. To form and subsequently maintain an electric arc, special equipment is used.

What do you need to weld at home?

To carry out the work, you will first need a welding machine. There are several varieties of it.

Let's decide which one to give preference to.

. A distinctive feature is the ability to generate electrical energy and use it to create an arc. It will be useful where there is no current source. It has impressive dimensions, so it is not very convenient to use.
Welding transformer. The device converts alternating voltage supplied from the mains into alternating voltage of a different frequency, which is necessary for welding. The devices are easy to operate, but have significant dimensions and react negatively to possible surges in mains voltage.
Welding rectifier. A device that converts the voltage supplied from the mains into the direct current necessary to form an electric arc. They are compact and highly efficient.

For work at home, an inverter-type rectifier is preferable. They are usually called simply inverters. The equipment has very compact dimensions. When working, it is hung on the shoulder. The principle of operation of the device is quite simple.

It converts high frequency current into direct current. Working with this type of current ensures the highest quality weld.

The welding generator can operate in the absence of a network. It generates the current itself. The system is very cumbersome and quite difficult to work with.

Inverters are economical and operate from a household network. In addition, it is better for a beginner to work with them. They are extremely easy to use and provide a stable arc.

The disadvantages of inverters include higher cost than other devices, sensitivity to dust, moisture and power surges. When choosing an inverter for home welding, pay attention to the range of welding current values. The minimum value is 160-200 A.

Additional features of the equipment can make the job easier for a newbie.

Among these pleasant “bonuses” it is worth noting:

Hot Start– which means an increase in the initial current supplied at the moment the welding arc is ignited. This makes it much easier to activate the arc.
Anti-Stick– automatically reduces the welding current if the electrode rod is stuck. This makes it easier to pull off.
Arc Force– increases the welding current if the electrode is brought to the workpiece too quickly. In this case, sticking does not occur.

In addition to any type of welding machine, you will need electrodes. It is best to select their brand using a special table, which indicates the type of material being welded.

You will also need a welding helmet. The best one is the one that goes on the head. Models that need to be held in the hand are extremely inconvenient.

When working with welding, you only need to wear a protective suit. A special mask will protect your eyes from ultraviolet radiation and splashes, a thick suit and canvas gloves will prevent burns.

The mask may have a simple tinted glass or a so-called “chameleon”. The latter option is preferable, since when an arc appears, the glass automatically darkens.

It is necessary to work only in special clothing that protects from splashes and ultraviolet radiation. This could be thick cotton overalls, boots or high boots, canvas or rubberized gloves.

Electric welding technology

It is better to learn how to properly weld parts using electric welding under the guidance of experienced welders. If for some reason this does not work out, you can try it yourself. First you need to properly organize your workplace. This is very important, since welding is a high-temperature and therefore fire-hazardous process.

To work, you need to choose a workbench or any other base made of non-flammable material. Wooden tables and similar products are strictly prohibited. It is advisable that there are no flammable objects near the place where welding will be carried out.

Be sure to place a bucket of water near you to eliminate possible fires. In addition, you need to determine a safe place where the remains of used electrodes will be stored. Even the smallest of them can cause a fire.

You can find welding electrodes of different diameters on sale. The required rod size is selected based on the thickness of the metal being welded

For the first independent seams, you need to prepare an unnecessary piece of metal and select electrodes for it. Experts recommend using 3 mm rods in such cases. The smaller diameter is used for welding thin sheets, which are inconvenient to learn from. Larger diameter electrodes require high power equipment.

We start by stripping the area of metal where the seam will be located. There should be no rust or any contamination.

After the part is prepared, take the electrode and insert it into the clamp of the welding machine. Then we take the “grounding” clamp and firmly attach it to the part. Let's check the cable again. It should be tucked into the holder and well insulated.

Now you need to select the operating current power for the welding machine. It is selected according to the diameter of the electrode. We set the selected power on the panel of the welding equipment.

The next step is igniting the arc. To do this, you need to bring the electrode to the part at an angle of about 60° and very slowly move it along the base. Sparks should appear. As soon as this happens, lightly touch the part with the electrode and immediately raise it to a height of no more than 5 mm.

The welding inverter is ready for use. Two cables are connected to it: one with a clamp for the electrode, the second with a grounding clamp

At this moment, an arc flashes, which must be maintained throughout the entire operation. Its length should be 3-5 mm. This is the distance between the end of the electrode and the workpiece.

When maintaining the arc in working condition, you need to remember that during operation the electrode burns out and becomes shorter. If the electrode gets too close to the workpiece, sticking may occur. In this case, you need to slightly swing it to the side. The arc may not ignite the first time. Perhaps there is not enough current, then it needs to be increased.

After the novice welder has learned to ignite the arc and keep it in working condition, you can begin to weld the bead. This is the simplest of all operations. We light the arc and begin to very smoothly and carefully move the electrode along the future seam.

At the same time, we perform oscillatory movements resembling a crescent with a small amplitude. We seem to be “raking” the molten metal towards the center of the arc. This way you should get an even seam that looks like a roller. There will be small wave-like metal sagging on it. After the seam has cooled, you need to knock the scale into it.

Arc welding techniques - welding methods

To get a high-quality seam, you need to learn how to maintain and then move the arc. The length of the electric arc especially affects the quality. If it is more than 5 mm, then it is considered long.

In this case, nitriding and oxidation of the molten metal occurs. It splashes out in drops, making the seam porous and not strong enough. If the arc is too short, lack of penetration may occur.

The electrode rod can move along different trajectories. With experience, each welder chooses “his own” option, or more often a combination of several movements

Various techniques are used to perform welding. Let's look at the main ones in detail.

Option #1: Bottom Butt Joints

The most common and simplest way to connect parts. For metal thicknesses up to 0.8 cm, double-sided welding is used. For connections made of metal thinner than 0.4 cm, only one-sided welding is performed.

For work, electrodes are selected whose diameter is equal to the thickness of the metal. If it exceeds 8 mm, welding is carried out with cutting edges. In this case, the cutting angle is about 30°.

Welding is performed in several passes. It is advisable to use removable pads made of steel or copper to avoid burns. The first pass is performed with a small diameter electrode, no more than 4 mm.

When making the first seam, its accuracy and penetration depth are very important. After applying it, there should be no fused metal behind the edges.

For the second and all subsequent passes, larger diameter electrode rods are used. They are chosen for high-quality filling of the recess formed between the edges.

The electrode is slowly moved along the seam, performing oscillatory movements, as if rocking the electrode from side to side, in order to completely fill the voids with molten metal.

Option #2: Bottom Corner Joints

Experienced welders claim that good results can be achieved by welding corners “in a boat”. This means that the parts to be connected are installed at an angle of 45° or other.

This ensures the highest quality penetration of the product walls, and the danger of undercutting and lack of penetration is reduced. This welding method allows welding of large cross-section seams to be deposited in one pass.

Craftsmen remind that when welding a T-type corner joint, the electric arc should be ignited only on a horizontal plane (+)

There are two types of boat welding - symmetrical and asymmetrical:

The inclination of the parts is 45°. The likelihood of sagging or undercutting one of the walls is minimal. Welding of reverse and direct polarity is carried out at maximum current values. When carrying out reverse polarity welding, the length of the electric arc should be minimal.
Tilt of parts at an angle of 60° or 30°– asymmetrical “boat”. This option is very convenient if work is carried out in hard-to-reach places, since the amplitude of movement of the electrode is small. The welder directs the arc to the very root of the seam, and care must be taken that it does not go beyond the boundaries of the future seam. It is also not allowed to deposit too much metal in one pass.

Corner joints can be T-type, so you need to learn how to weld metal correctly and without errors using electric welding in several passes.

The use of one pass is only possible when welding simple structures with sides that form an angle of 45° in a fillet weld. The diameter of the electrode in this case cannot exceed the thickness of the metal by more than 0.15-0.3 cm.

Standard multi-pass T welding is performed as follows. For the first pass, an electrode with a larger diameter is taken than those selected for subsequent passes. For example, an electrode is used whose dimensions vary from 0.4 to 0.6 cm.

Some welds are made in multiple passes. In this case, the size of the electrode for the first pass and for all subsequent passes is different.

Welding is carried out smoothly, without transverse oscillatory movements. When performing other passes, they are necessarily carried out. It is important that the vibration amplitude is within the permissible seam width.

Another significant point. When performing T-welding on a fillet joint, the electric arc should always be ignited on a shelf positioned horizontally.

When doing electric welding of corners with your own hands, you can use an overlap type of connection. In this case, the parts to be welded are placed one on top of the other with an overlap. The arc during direct polarity welding should be short, and during reverse polarity welding it should be as short as possible. Direct the arc exactly to the root of the connection.

During the welding process, it is necessary to perform small amplitude reciprocating movements with the electrode. This will allow the entire joint area to be heated evenly. In this case, the weld pool will be evenly filled, and the seam will be convex and full-sized.

Option #3: vertical seams

Seams directed vertically are made only with a short arc. In this case, the working current should be 10% -20% less than when welding parts in the lower position. These requirements are easy to explain.

A lower current strength means that the molten liquid metal will not drain from the weld pool. A smaller arc is more convenient to use.

Welding vertical seams has its own characteristics. They are explained by the fact that in this position, liquid metal can flow down the seam. Therefore, the welding current and electrode angle must be selected correctly

Experienced welders prefer to weld vertical seams from the bottom up. The arc is set on fire at the lowest point of the future seam. After that, a small horizontal platform is prepared, the dimensions of which correspond to the cross-section of the future seam.

Then slowly move the electrode rod up. In this case, movements across the connection must be performed.

They can be in the form of a herringbone, corner or crescent. The last option is the easiest to implement. In addition, it is important to maintain the correct position of the electrode. Theoretically, penetration is best achieved if the rod is positioned perpendicular to the seam, that is, horizontally.

Practice shows that in this position of the electrode rod, liquid metal flows down the seam. To avoid this, the angle of inclination of the rod is chosen within the range of 45°-50°. This is the optimal option for vertical welding. To weld parts in the bottom-up direction, select electrodes whose diameter does not exceed 0.4 cm.

Option #4: Pipeline Details

At home, you often have to remember how to electric weld a metal pipe. A vertical seam is usually made on the side of the part, and a horizontal seam along the circumference. butt welded. All edges must be well boiled.

To ensure that the sagging inside the pipe is minimal, the electrode is brought to the product at an angle of no more than 45°. The seam width should be 0.6-0.8 cm, height – 0.2-0.3 cm.

Pipe welding is carried out using various seams and in different areas. Depending on the wall thickness of the part and its location, the diameter of the electrode and the type of seam are selected

Before starting welding work, the parts to be joined are thoroughly cleaned. The ends of the pipe are inspected. If they are deformed, they are straightened or. Then the edges of the parts are cleaned from the inside and outside to a metallic shine at a distance of at least 1 cm from the edge. Then start welding.

The joint is welded without interruption until it is completely welded. For non-rotating joints of pipes with walls up to 0.6 mm wide, two welding passes are performed, for products with walls from 0.6 to 1.2 cm wide - three passes, for parts with walls wider than 1.9 cm - four passes.

In this case, each subsequent seam is applied only after the scale has been removed from the previous one.

The quality of the first seam is most important. During the process, all blunts and edges should completely melt. There should be no cracks, even the smallest ones. If they exist, they are smelted or cut down. After which the fragment is welded again. Welding of rotary pipes is performed in the same way.

Possible defects in welding joints and seams

Electric welding is a complex process and not always everything goes smoothly.

As a result of operational errors, seams and joints may have various defects, including:

Craters. Small depressions in the weld bead. They may appear as a result of a broken arc or an error in the execution of the final fragment of the seam.
Pores. The welding seam becomes porous as a result of contamination of the edges of the parts with rust, oil, etc. In addition, porosity can appear when the seam is cooled too quickly, at high welding speeds and when working with undried electrodes.
Undercuts. They look like small indentations on both sides of the suture bead. Appear when the electrodes are displaced in the direction of the vertical wall when welding corner joints. In addition, undercuts occur when working with a long arc or when the welding current is too high.
Slag inclusions. There are pieces of slag inside the welding bead. This can happen if the edges are dirty, the welding speed is high or the welding current is too low.

If desired, any home craftsman can master the basics of welding. It is not so difficult. It will require patience, accuracy and, of course, precise execution of all instructions. Everything will be much easier if the process of mastering a new skill takes place under the guidance of an experienced specialist.

In order to be able to carry out work related to connecting elements of metal structures at any time in a home workshop or on a personal plot, it is enough to purchase a modern welding machine and learn how to weld with a welding inverter.

Welding work has long been widespread not only in serious production, but also in everyday life.

Design and advantages of inverter welding machines

The great popularity of inverter equipment among home craftsmen is explained by the fact that with the help of such compact devices, which are also lightweight, it is possible to make high-quality, reliable and accurate welded joints, even without high qualifications.

The design of any welding inverter consists of such elements as:

power supply with rectifier unit and filter;
inverter unit that converts direct current into high-frequency alternating current;
transformer for reducing the voltage of high-frequency current;
power rectifier designed to produce direct current at the output of the device;
an electronic unit that performs device control functions.

Innovative technologies implemented in the design of inverters make it possible to obtain high-quality welded joints without any problems. Due to their compactness, such devices do not take up much space, and due to their light weight (5–15 kg), they can be moved anywhere without much difficulty.

If you learn how to work correctly, you can use it to weld any metal structures. Each new inverter comes with instructions, from which the owner of the equipment can glean a lot of useful information: how to properly connect the device, which electrode to choose in order to weld products from a particular metal, etc.

Patterns of electrode movement depending on the type of seam (click to enlarge)

However, often an inverter device falls into the hands of a home craftsman, the instructions for which are not translated into Russian or are missing altogether. It is very important to learn correctly, because if you act at random, it will be difficult to weld metal well. In addition, you may encounter equipment failure.

However, if you follow generally accepted rules, you can work on any model of inverter and effectively solve all the tasks. After carefully studying these rules, watch the training video, which will help reinforce the theoretical material with visuals.

How to prepare equipment for operation

Before you start welding metal, prepare all the necessary equipment to ensure your safety: a welding mask, special clothing made of thick fabric, work shoes and gloves, which should also be made of thick material.

In order for the weld to be of high quality, it is necessary to select the correct electrodes. Their type and diameter are selected depending on the metal from which the parts being joined are made, the thickness of the latter, as well as the welding modes. Since the surfaces of the workpieces to be welded must be thoroughly cleaned, you also need to prepare a brush with metal wire bristles.

Before connecting the inverter to the electrical network, you need to check whether the network parameters correspond to the characteristics of the connected equipment.

These parameters include the strength of the electric current and the voltage value, which must be within the range specified in the passport for the inverter. The device should be connected to the power supply through an automatic circuit breaker, which will prevent equipment breakdown if a short circuit occurs in its electrical circuit or the voltage increases sharply for another reason.

Before starting welding, it is necessary to take care of the condition of the working site. The inverter should be installed on a flat surface, and there should be enough space around its body to ensure free movement of air, due to which the device is naturally ventilated. Do not cover the device body with fabric, which will restrict the flow of air to its ventilation grilles.

The welding process is accompanied by high temperatures and splashing of molten metal, so there should be no flammable, fire or explosive substances on the work site.

After all preparatory activities have been completed and safety requirements have been met, you can proceed to the following actions:

connecting the power cable and ground cable to the corresponding connectors of the inverter;
fixing the mass cable on the parts to be welded (a special clamp is used for this);
connecting the device to the power supply and setting welding operating modes on it;
fixing the electrode in the welding holder.

The sequence and correctness of performing such actions is well demonstrated by the training video. Now that the inverter is connected to the electrical network and the electrode in its holder is ready for use, you can begin welding.

Features of welding work using inverter devices

The first thing you need to do to start cooking with an inverter is to light an electric arc between the surface of the part and the tip of the electrode. To do this, the latter makes a scratching movement along the surface of the workpiece, as a result of which a bright flash should appear. The metal in the arc zone will begin to melt. You can learn how to light an arc correctly and do it quickly by watching a training video.

When performing welding, it is important to monitor the length of the arc, which should approximately correspond to the diameter of the electrode used (in this case, the parts will be evenly melted, which will allow the formation of a high-quality weld). It is necessary to ensure that such penetration occurs evenly throughout the entire welding process.

The quality and reliability of the weld is also influenced by the polarity of connecting the inverter power cable and the ground cable. To choose this polarity correctly, you need to know exactly what material the parts being connected are made of. Most grades of steel and other metals are best welded with direct polarity; only some alloys are combined with reverse polarity.

The design of modern welding inverters ensures smooth and efficient regulation of the operating current, which makes working with such devices simple and comfortable even for novice welders. You can judge that the welding current is selected incorrectly based on a number of factors. So, if it is too small, then the weld seam turns out to be too convex and narrow, and the parts in such cases are poorly fused. If the current is too high, then intense spattering of molten metal occurs, and burns may appear on the surface of the parts being connected.

The choice of welding current depends on the diameter of the electrode you are going to weld with. Thus, when welding metal with a thickness of one to three millimeters with electrodes with a diameter of up to 1.5 mm, the welding current strength is selected in the range of 20–60 A. In the event that larger diameter rods are used, which can be used to weld metal 4–5 mm thick, the strength welding current is selected within 100 A.

While watching a training video or watching the work of a qualified specialist, novice welders are often interested in why slag is knocked off the surface of the finished weld. This is done in order, firstly, to check the quality of the weld, and secondly, to give the finished joint an attractive appearance. A seam cleared of slag shows all the mistakes made during welding.

Of course, you should not expect that novice welders (or so-called dummies) will immediately produce beautiful and high-quality welds. Mastery, including in welding, does not come immediately after familiarizing yourself with theoretical material and watching videos; it is developed only through experience.

How to choose the right welding inverter and electrodes for it

Correctly selected electrodes play a big role in the formation of a high-quality and reliable welded joint. It is impossible to learn how to choose them from a video; to do this, you should adhere to generally accepted recommendations and the following principles.

When working with medium and low carbon steels, carbon electrodes are used.
Alloy steels are welded using electrodes produced in accordance with GOST 10052-75 and 9466-75.
For welding cast iron products, OZCh-2 grade products are used.

Classification of electrodes by type and purpose (click to enlarge)

Comments:

People who live in their own home, have a dacha or at least a private garage, periodically face the need to carry out welding work. As a rule, they use the services of professional welders. However, many, if they want to save money or simply out of interest, cook on their own, using specialized equipment for this. If you are one of those people who like to do everything on their own, but you have never had to work with electric welding before, there is no need to be afraid. You can learn everything, including electric welding. The most important thing is to familiarize yourself with the theory and practice a little. And very soon you will produce seams no worse than those of a professional welder.

Preparation for work and selection of electrodes

Before you start learning to weld with electric welding, you should prepare the required tools and protective accessories. Prepare the following:

welder's mask;
protective clothing and gloves;
hammer for removing slag;
electrodes;
metal brush;
welding machine.

Protective clothing must be made of dense material.

Before starting work, remember one simple rule: electrodes must be selected in accordance with the thickness of the metal, and the current must be set according to the selected electrode. The calculation is extremely simple. For example, you are using a welding transformer.

In this case, 1 mm of electrode will account for about 30-40 A. If you work with a welding inverter, then 3 mm of electrode will correspond to 80 A. When the current increases to 100 A, it will already be possible to cut metal.

The place for welding work should be convenient for you. There are no special requirements for it. Be sure to bring a bucket of water to your workplace.

Prepare everything you need for work, as well as the workpieces themselves. Thoroughly clean the weld seams using a metal brush. Until you have experience, if possible, position workpieces using a vice or clamps.

In order to understand the technology of working with electric welding, first practice welding beads on a flat area. In this case, it is best to use 3 mm electrodes - the most popular and universal option.

You should not hope that you will be able to learn how to weld with electric welding “with 1 electrode.” Prepare at least a pack of electrodes. They're relatively cheap, but you'll get plenty of practice.

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Step-by-step instructions for working with electric welding

To begin, attach the work clamp to the workpiece and insert the electrode into the holder. Next, you will need to light the arc. To make everything simpler and clearer, while working, imagine that the electrode is a pencil. It will need to be installed at an angle of about 70 degrees to the workpiece. Having chosen the optimal location of the electrode, move it across the workpiece at a speed of approximately 7-10 cm per second. If a characteristic crackling sound and sparks appear, everything has been done correctly.

Next, at approximately the same angle, you will need to touch the workpiece and immediately lift the electrode so that a gap of 3-5 mm is obtained. As a result, the arc will begin to burn. In this case, both the metal of the workpiece and the arc itself will melt. You must try to maintain this gap and at the same time move the electrode horizontally.

If the electrode begins to stick, shake it from side to side, tearing it away from the workpiece, and re-ignite the arc.

If the electrode sticks, this is a clear sign that the current is too low. Therefore, it needs to be increased slightly. Practice, change the current until you find a value at which the arc length between the part and the end of the electrode will be 3-5 mm.

Once you have learned how to strike an arc and maintain it in a stable state, you can learn how to build a bead. Clamp the arc and begin to smoothly move the electrode along the welding seam, i.e. horizontally. During such movement, you need to make movements with an amplitude of about 2-3 mm, as if “raking” the molten material towards the arc crater. This is how a beautiful seam with barely visible waves of deposited metal is created. The seam is quite reliable.

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How to make different seams?

However, the seam discussed above is not the only one available. Before moving on to studying different seams, you need to remember that the main condition for high-quality welding is proper maintenance and movement of the arc. If the arc is too long, the molten metal will begin to oxidize and nitrate, its drops will be splashed across the surface, and the seam will have a porous structure.

The principle of electrode welding.

The movement of the arc can be carried out in 3 main directions. In the first case, translational motion occurs along the axis of the electrode. In this case, the length of the arc will be maintained in normal condition. It depends on the melting rate of the electrode. As it melts, the distance between it and the weld pool will increase. To prevent this, move the electrode along the axis. Due to this, the arc will have a constant length.

When the electrode is moved longitudinally along the axis of the seam, the so-called thread welding bead discussed earlier. The thickness of such a seam depends on the diameter of the electrode used and how quickly it moves. The width of the roller in most cases exceeds the diameter of the electrode by 2-3 mm. The bead is already a weld, but it is too narrow. It is usually not enough to create a strong connection. For this reason, when moving the electrode along the axis of the seam, you need to make another movement, but this time across.

A seam of the required length can be obtained by transverse movement of the electrode. In this case, reciprocating oscillatory movements are performed. In each specific case, the width of these fluctuations is determined individually. First of all, it is influenced by the size and position of the seam, the shape of the groove, the characteristics of the working materials, as well as the requirements for the welding joint itself. In most cases, the width of the seam does not go beyond 1.5-5 diameters of the electrode used.

When working with electric welding, the appropriate arc movement should be selected in such a way that the edges of the joined products are fused to form the required amount of deposited metal and a weld of a given shape.

In the modern world, welds are found almost everywhere, in every industry. But many owners resort to the services of specialists. But you can easily acquire this skill yourself, especially since the welding process is very exciting; you may be drawn from welding an ordinary garage to making an openwork fence. It’s not difficult to learn how to cook; just understand the nuances and you can safely move on to the welding process.

Before you begin any training and understand how to properly weld with electric welding, you need to stock up on certain accessories. For welding you need to purchase:

Welding machine - electric welding.
Set of electrodes. Their diameters vary and must be selected depending on the density and thickness of the metal section. Necessary for supplying current to the welding seam. For beginners, you can purchase rods with a heating and easily melting composition.
Long sleeve rubber gloves. It is recommended to wear suede ones.
Mask with a darkened light filter.
Thick clothes.
A hammer needed to knock down slag (glassy material).
Brush for cleaning seams.
Transformer – used to convert direct current to alternating current. It is used, as a rule, when there is no need for a high-quality weld.
Rectifier.

Instead of a transformer and rectifier, for a beginner you can use a simpler mechanism - an inverter. It is very convenient and versatile. They can be used to weld both aluminum alloys and durable steel alloys. It also comes with a pair of wires with clamps attached to them. An electrode is inserted into one end, and the parts necessary for welding are attached to the other.

When welding, do not forget about safety measures.

Before starting welding work, it is necessary to prepare the working surface. To do this, you need to remove rust from surfaces by treating it with sandpaper, a grinder or sandpaper. If you ignore this procedure, problems may arise when igniting the arc.

Electric welding process technology

Welding is a process cultivated under the influence of high temperatures. Under its influence, the treated surfaces melt, forming a so-called bath in which the base metal is mixed with the metal core of the electrode.

The size of the resulting pool can be different, depending on the initial type of welding, position to the surface, speed of arc movement, and so on. On average, the welding width can be 0.8 - 1.5 cm, height 1 - 3 cm, and depth about 0.6 cm.

Oxygen, when combined with metal, can have an undesirable effect on the joining of the seam, which is why the electrode is covered with a special coating, which, when melting, forms a zone of gas in the arc area and above the molten pool, into which air does not enter. This is why the metal does not interact with oxygen. In addition, slag forms on top of the seam, which also prevents the interaction of the alloy and oxygen. At the final stage, it is cleaned with a brush.

Arc striking training

Before any type of activity you need to gain experience. Likewise in the welding process, before you start alloying several metals, you need to practice making beads on an unnecessary sheet of metal. To do this, you need to clean the rusty surface and dirt on it.

The electrode is then clamped into the welding machine holder (inverter). Next, in order to deliver current to the melting zone, you just need to scratch. Or you can also do it with tapping movements.

After the completed electric arc is created, the electrode is directed to the workpiece. It is worth noting that the gap between the electric arc and the metal surface should be the same throughout the entire gap, but not less than 0.3 cm and not more than 0.5 cm.

Important! If the gap between the arc and the metal is changed, the electric arc will break, and the welding seam will be defective and unsightly.

The electric rod is usually held at an angle of 71 degrees. It can be tilted forward or backward, as is more convenient for the master. In the future, the tilt can be changed depending on the convenience of the master or on the specifics of welding.

And also at this training stage, it is necessary to feel the required electric welding current in order for the supply to be carried out stably. If the current strength is small, then the electric arc will go out, and if, on the contrary, it is large, then the metal will begin to melt. Welding skills can be gained through trial and error.

Weld seams depending on welding speed

Correct movements with the electrode

After training with rollers, which after hard training should turn out approximately smooth and beautiful, you can begin training welding seams. It is at this stage that you can understand how to correctly lay perfect seams using electric welding. This stage is already within the capabilities of beginners who have gotten good at using rollers, felt the required current strength, the distance between the gaps, etc.

For a welded seam, you must first prepare the equipment, as described above (light an electric arc). A distinctive feature from the previous stage is that this time the master’s hand moves not in a straight line, but along an oblique path, making light oscillatory movements with a small amplitude. It looks as if the master is moving hot, melting metal from one edge of the welded element to the other.

The movement can be different and can be a zigzag, looping or reminiscent of repeated bends similar to Christmas trees and sickles.

There are trajectories produced in three directions:

Progressive. The electrode moves along its axis. For this purpose, maintaining a stable electric arc length will be sufficient.
Longitudinal. This is one of the thinnest types of seams. It looks like a thread. In order to apply it, it is necessary to maintain a height that depends on the speed at which the electric rod moves. In order to secure the resulting seam, it is necessary to make transverse directions of movement.
Oscillatory. This trajectory helps to obtain the required seam width. They can be done by making oscillatory movements of the hand. The height of the vibration wave is selected based on the size of the desired joint.

Electrode manipulation

The training also needs to be done on an unnecessary metal sheet. To begin, draw a line with chalk so that it can be seen through the darkened glass of the welding helmet. Next, along this line you need to draw a seam with an electrode along one of the trajectories listed above. After the joint has cooled, the slag is knocked off with a hammer, and a beautiful seam is obtained.

After obtaining these initial skills, you can safely begin welding connecting seams. They come in completely different shapes: horizontal, vertical, angular, butt, overlapping and others. After you feel that your hand is moving more or less confidently and have trained a lot, you can only then try to weld beautiful and delicate seams.

For a visual understanding of the welding process, we recommend watching this video

Thus, you can independently learn the very necessary skill of working with electric welding. To do this, you need to stock up on certain supplies and tools. It is also worth remembering that welding is a very dangerous activity, so when working with it you need special equipment and protective measures (helmet, gloves, clothing). To master this type of work, you must first practice on an unnecessary sheet of metal.

Welding is one of the affordable and reliable ways to firmly connect metal products. In a private house, in a garage or in a country house, there is always work related to welding: repairing a hole in a watering barrel, building a fence, repairing a metal table, and more. Usually they turn to professionals, but if you need to do simple work and the beauty of the seam is not of great importance, then you can do the welding work yourself. It is better if the first lessons are taught by an experienced master, but in some cases you have to learn the basics of electric welding yourself. The simplest, most accessible and popular is electric arc welding, which is why almost all craftsmen whose work is related to metal use it.

What is manual arc welding?

The manual arc welding process involves using an inverter or transformer to create an electric arc between the tip of the electrode and the surface of the metal. The elevated temperature melts the metal and electrode, promoting fusion of the materials. (Fig. 1) The place where the metal is connected to the electrode is called the weld pool. Standard bath sizes:

width 7-15 mm;
length 10-32 mm;
depth 5-6 mm.

The parameters of the weld pool are arbitrary and depend on various factors: welding mode, shape of the edges of the products being welded, speed of movement of the electrode, and others.

When the electrode melts, its coating forms a protective gas layer that prevents the metal from burning through and also protects it from exposure to oxygen. A weld seam is formed, covered with a layer of slag. The slag is subsequently removed using the welder's hammer.

Manual arc welding is very popular due to the advantages:

availability;
available supplies and equipment;
does not require re-adjustment of equipment for welding different materials;
good seam quality.

Tools and protective equipment for welding

For manual welding you will need: a welding machine, consumables in the form of electrodes, a metal brush, a hammer, a chisel and a mask with a light filter (welder mask).

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Welding machines for manual arc welding:

Transformers - work with alternating current. They are heavy, make a lot of noise, form an unstable arc and affect the electrical network, causing voltage surges. Only an experienced welder can make an even weld on a transformer. However, if you learn how to weld on a transformer, then with other devices it will be much easier.

Rectifiers - convert alternating current into direct current, operate on the basis of semiconductor diodes. The rectifier is universal; it can be used to weld a wide variety of metals and use any electrodes. Unlike a transformer, a rectifier produces a stable arc, which makes the welding process easier.

Welding inverters are compact in size, have automated settings, and are quieter than transformers. This device converts alternating current into high power direct current.

Advantages:

accuracy of settings;
multifunctional;
forms a stable arc;
does not depend on voltage surges;
Works with any types of electrodes.

All these advantages provide an even, high-quality seam.

Flaws:

need to be frequently cleaned of dust;
Do not work at temperatures below -15°C.

Some useful tips:

If you are just starting to learn welding in practice, then it is better to start with an inverter. It's much easier and more convenient to work with
Don't forget the hammer and chisel you'll need to knock the slag out of the seam. Next, the seam is cleaned with a wire brush.
We must not forget about protective equipment. You must have a welding mask with a light filter that protects your eyes.
The suit should be canvas, with long sleeves. The trousers are smooth, without cuffs. It is better to choose shoes that are as closed as possible, for example, leather.
Another attribute is canvas or suede gloves or mittens of sufficient length.
It also doesn’t hurt to take care of fire safety, for example, prepare a bucket of water.

Preparation for the process

Before starting work, you need to prepare the welding machine:

Check the voltage and frequency values, the data must match both in the network and on the device body;
If there is a voltage selection mode, it is better to set it right away, then set the current value. The power parameter must correspond to the electrode number, that is, the diameter.
Check the cable insulation. Securely fasten the grounding clamp.
Check all cables, whether they are insulated, connections, plugs.
Insert the electrode into the holder, which can be screw or spring. Be sure to make sure that the electrode is held tightly.

For example, an inverter has two cables. One is connected to the part, the second holds the electrode. They are supplied with different current values: plus – to the part, minus – to the electrode with “straight polarity”. In some cases, it is necessary to cook in the “reverse polarity” mode, that is, plus on the electrode, minus on the part.

The welding site must also be prepared. It is necessary to clean the metal surface from any dirt, rust, scale, oil. Most weld defects are caused by a poorly prepared surface. Before welding, electrodes must be checked for integrity: its coating must be uniform, without chips. It is also often necessary to dry or calcinate consumables.

Another important question: what current to set. The higher the current, the more stable the arc, but a very high value can burn through the metal. The set current directly depends on the electrode number and the thickness of the part. For horizontal welding, you can focus on the following amperage values: (Table 1)

For vertical welding, the values should be reduced by 15%, for ceiling seams - by 20%. However, in practice, many other factors interfere with the welding process, so the correct amperage can only be determined experimentally.

How to cook correctly?

Welding begins with ignition of the arc. There are two ways to ignite an arc:

Touch. The electrode is held at an angle of 60°, then the end of the electrode touches the metal and immediately raises the electrode to a distance of 3-5 mm. An arc is formed.
Scratching. The tip of the electrode is quickly passed along the surface of the metal and then quickly raised by 2 mm.

It is optimal to maintain an arc length of 5 mm. If you bring it too close, the electrode will stick, but a long arc does not cook the metal and creates a lot of splashes. If sticking occurs too often, it means that the current is not enough and you should add more. The length of the arc can be controlled by sound: if the sound is smooth, monophonic, then the length is constant, but if sharp sounds with pops are formed, then the length is too long.

As soon as the welder catches the arc, he begins welding. The electrode is slowly and smoothly moved horizontally, performing light oscillatory movements. If suddenly the arc breaks or the electrode burns out before the seam is completed, then you need to continue working correctly. At the end of the seam a depression (crater) is formed. You need to step back about 12 mm from it and light the arc. Moving slowly forward, carefully weld the crater and continue welding the seam.

As a rule, they are welded in several layers:

parts up to 6 mm thick in two layers;
workpiece 6-12 mm - in three layers;
parts with a thickness of more than 12 mm - 4 layers.

The trajectory of the arc is divided into types:

Translational - the electrode simply moves along the axis of the electrode;
Longitudinal - for forming a thin thread seam;
Transverse - oscillatory movement of an electrode of a certain width (Fig. 2)

Usually the master combines all three trajectories. At the same time, it is necessary to control the distance between the electrode and the surface, since the electrode burns out and decreases in length. You also need to monitor the condition of the bathtub, its size, in order to increase or decrease the speed of movement in time.

It must be remembered that it is impossible to weld parts immediately with a continuous seam, this will lead to distortion of the metal. Two workpieces are connected with clamps or in another way, then spot seams are made at a distance of 8-25 cm from each other, depending on the length of the seam. It is recommended to make spot welds on both sides to avoid stress on the metal. And only then start making the main seam.

Types of seams

Connecting seams are:

T-bars;
butt;
corner;
overlapping

Based on their location, welds are divided into: ceiling, horizontal, and vertical. (Fig. 3)

The horizontal seam is the simplest; the electrode is lowered to the bottom at an angle of 60-70 degrees. (Fig. 4)

Vertical seam - the electrode is guided vertically from bottom to top or top to bottom. It is better to hold the electrode at an angle of 45-50° down from the vertical position so that the metal does not drain. It is advisable to make the seam in one pass. (Figure 5).

The ceiling seam is the most difficult. The weld pool is located at the top, above the welder and turned upside down. The electrode moves towards itself, over a very short arc. It is advisable to cook with 3-4 mm electrodes (Fig. 6)

Basic mistakes of newbies

To learn how to cook correctly, you need not only to know the basics, but also what common mistakes beginners make:

The electrode is moved too quickly, which results in an uneven seam with uncooked areas; (Fig. 7)
Moving the electrode too slowly leads to burning in the metal and the formation of holes (Fig. 8);
Incorrect current supply: a very high current can burn through the metal, and an insufficiently strong current may not weld the seam and will cause the electrode to stick to the surface.
An incorrectly chosen angle can lead to an uneven and flat seam.
Incorrect gap between electrode and metal. If it is too small, then the workpiece metal does not heat up well. An arc that is too long results in a shapeless, weak seam (Fig. 9).

In general, the speed of movement of the electrode must correspond to the current strength; the greater it is, the higher the speed of movement of the electrode should be.

Features of welding thin sheet metals

Welding thin sheet metals is more difficult, since such metal is easier to burn through. It is recommended to do the following:

Cook in reverse polarity mode, the current is minimal.
The shorter the length of the seam, the less warping, so they weld with an intermittent seam, sometimes moving to another joint area.
When butt welding, a minimum gap between the edges is achieved.
In overlap welding, the sheets are pressed tightly against each other during welding to prevent gaps.
If the metal thickness does not exceed 1.5 mm, it is recommended to use semiautomatic welding machines with wire, since conventional electrodes will burn through the workpiece.

Manual arc welding is a complex process, but with due diligence you can learn this business.