Private welder lessons. Manual Arc Welding Technique

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People living in own house who have a summer house 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, you should not be afraid. Everything can be learned, including electric welding. The most important thing is to get acquainted with the theory and practice a little. And very soon you will get seams no worse than a professional welder.

Preparation for work and selection of electrodes

Before you start learning to cook with electric welding, you should prepare the required tools and protective equipment. 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: the 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, about 30-40 A will fall on 1 mm of the electrode. If you work with a welding inverter, then 3 mm of the electrode will correspond to 80 A. When the current rises to 100 A, it will already be possible to cut metal.

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

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

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

Do not hope that you can learn how to cook with electric welding “for 1 electrode”. Prepare at least a pack of electrodes. They are relatively cheap, but you can get plenty of practice.

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Step-by-step instructions for working with electric welding

To begin, attach the ground 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. After choosing the optimal electrode position, sweep the workpiece at a speed of approximately 7-10 cm per second. If a characteristic crackle and sparks appear, everything is 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 be melted. It is necessary to try to maintain this gap and at the same time move the electrode horizontally.

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

If the electrode sticks, then it clear sign too little current. Therefore, it needs to be slightly increased. Practice varying the current until you find a value where the length of the arc between the workpiece and the end of the electrode is 3-5mm.

After you have learned how to strike the arc and keep it steady, you can learn how to weld a bead. Clamp the arc and begin to smoothly move the electrode along the welding seam, i.e. horizontally. During such movement, it is necessary to make movements with an amplitude of about 2-3 mm, as if “raking up” the molten material to the arc crater. This is how a beautiful seam is created with a barely visible waves deposited metal. The seam is characterized by a sufficiently high reliability.

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How to make different seams?

However, the seam discussed above is not the only one available. Before proceeding to the study of different seams, you need to remember that the main condition for high-quality welding is the competent maintenance and movement of the arc. If the arc is too long, then the molten metal will begin to oxidize and nitride, its drops will splatter over 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, doing forward movement along the axis of the electrode. In this case, the arc length will be maintained in the normal state. 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.

With the longitudinal movement of the electrode along the axis of the seam, the so-called. thread welding roller, discussed earlier. The thickness of such a seam depends on what diameter the electrode used has and how fast 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 too narrow. To create a strong connection, it is usually not enough. For this reason, moving the electrode along the axis of the seam, you need to make one more movement, but already across.

You can get a seam of the desired length due to the transverse movement of the electrode. In this case, reciprocating oscillatory movements are performed. In each specific case, the width of these oscillations is determined in 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, a suitable arc movement should be selected in such a way that the edges of the joined products are melted with the formation of the required amount of deposited metal and a weld of a given shape.

In a private house, in a country house, in a garage and even in an apartment - everywhere there are many jobs that require metal welding. This need is especially acute during the construction process. Here, especially often, something is required to be welded or cut off. And if you can still cut off with a grinder, then there is nothing to reliably connect metal parts except for welding. And if the construction is done by hand, then welding work can be done independently. Especially in those places where the beauty of the seam is not required. About how to cook by welding, we will tell in this article.

The basics of electric welding

Welded metal joints today are the most reliable: pieces or parts are fused into a single whole. This happens as a result of exposure to high temperatures. Most modern welding machines use an electric arc to melt metal. It heats the metal in the impact zone to the melting point, and this happens in a small area. Since an electric arc is used, welding is also called electric arc.

It's not quite The right way welding)) At a minimum, you need

Types of electric welding

An electric arc can be formed by both direct and alternating current. Welding transformers are welded with alternating current, inverters with direct current.

Working with a transformer is more complicated: the current is alternating, therefore the welded arc “jumps”, the apparatus itself is heavy and bulky. Still a lot of annoying noise, which emits during operation and the arc and the transformer itself. There is one more nuisance: the transformer strongly “sets” the network. Moreover, significant voltage surges are observed. This circumstance is very unhappy with the neighbors, and your Appliances may get hurt.

Inverters mainly operate from a 220 V network. At the same time, they are small in size and weight (about 3-8 kilograms), operate quietly, and have almost no effect on voltage. Neighbors won't know you've started using a welding machine unless they see you. In addition, since the arc is called direct current, it does not jump, it is easier to mix and control it. So if you decide to learn how to weld metal, start with a welding inverter.

Welding technology

For an electric arc to occur, two conductive elements with opposite charges are required. One is the metal part and the other is the electrode.

The electrodes that are used for manual arc welding are a metal core coated with a special protective compound. There are also graphite and carbon non-metallic welding electrodes, but they are used for special work and are unlikely to be useful to a novice welder.

When an electrode and metal of different polarity touch, an electric arc occurs. After its appearance, in the place where it is directed, the metal of the part begins to melt. At the same time, the metal of the electrode rod melts, being transferred with an electric arc to the melting zone: the weld pool.

How is a weld pool formed? Without understanding this process, you will not understand how to weld metal correctly (To increase the size of the picture, click on it with the right mouse button)

In the process, the protective coating also burns, partially melting, partially evaporating and releasing some hot gases. Gases surround the weld pool, protecting the metal from interaction with oxygen. Their composition depends on the type protective coating. The molten slag also coats the metal, helping to maintain its temperature. In order to properly weld by welding, it is necessary to ensure that the slag covers the weld pool.

The weld is obtained by moving the bath. And it moves when the electrode moves. This is the whole secret of welding: you need to move the electrode at a certain speed. It is also important, depending on the required type of connection, to correctly select its angle of inclination and current parameters.

As the metal cools, a slag crust is formed on it - the result of the burning of protective gases. It also protects the metal from contact with the oxygen contained in the air. After cooling, it is beaten with a hammer. In this case, hot fragments scatter, therefore eye protection is required (wear special glasses).

How to weld metal

Learning how to properly hold the electrode and move the bath is not enough for a good result. It is necessary to know some subtleties of the behavior of the joined metals. And the peculiarity lies in the fact that the seam “pulls” the parts, which can cause them to warp. As a result, the shape of the product can be very different from what was intended.

Electric welding technology: before starting the seam, the parts are connected with tacks - short seams located at a distance of 80-250 mm from each other

Therefore, before work, the parts are fixed with clamps, ties and other devices. In addition, tacks are made - short transverse seams laid through several tens of centimeters. They fasten the parts, giving the product a shape. When welding joints, they are applied on both sides: in this way, the resulting stresses are compensated. Only after quiet preparatory measures begin welding.

How to choose a current for welding

It is impossible to learn how to cook by electric welding if you do not know which current to set. It depends on the thickness of the parts to be welded and the electrodes used. Their dependence is presented in the table.

But with manual arc welding, everything is interconnected. For example, the voltage in the network has dropped. The inverter simply cannot supply the required current. But even under these conditions, you can work: you can move the electrode more slowly, achieving good heating. If this does not help, change the type of electrode movement - several times passing through one place. Another way is to put a thinner electrode. By combining all these methods, a good weld can be achieved even under such conditions.

Now you know how to cook by welding. It remains to develop the skills. Choose a welding machine, buy electrodes and a welding mask and start practicing.

To consolidate the information, watch the video tutorial on welding.

Welding inverters (with their own low price in 7-10 thousand) forms high-quality seams, even if they are in the hands of beginners. Of course, the work will turn out good if you follow simple rules. All of them are described in the article. However, before work, beginners need to read the instructions for the device. There are usually several useful tips as well as safety precautions. Remember that everyone can learn to weld metal.

How a welding inverter works

Welding inverter - a tool for welding metal. It got its name from the fact that it converts alternating current into direct current. And although the inverter efficiency is about 90%, its power consumption is low, so you don’t have to worry about high electricity bills.

Most of all welding inverter operates on a 220 volt network, some types - from 380. At the same time, it is possible to work at low voltage: a 3 mm electrode, for example, can be used at 170 volts.

It is much easier to weld with an inverter, compared to a transformer or rectifier. In addition, even a beginner can hold the arc. That is why most people learn the art of welding on it.

Preparation for work

What electrodes to use

The electrode is a rod made of metal, which is coated with a special coating - a slag mixture. Gas-forming substances are sometimes added to it. Coating will protect the molten metal from oxidation.

The rod is selected depending on the type of metal to be welded. For example, to work with carbon or stainless steel, you will need the UONII electrode grade. There are also universal electrodes. These include the ANO brand. They are used in reverse and direct current any polarity.

The electrodes are also divided by diameter, which varies from 1.6 mm to 5 mm. The size is selected depending on the thickness of the metal being welded: the larger it is, the larger the diameter. A table may come in handy when working with a welding machine.

The thicker the rod, the more power the inverter welding machine must have. Therefore, for beginners, a diameter of no more than 4 mm is suitable; thin metal can be welded with an electrode and in 2 mm.

Polarity and value of welding current

The thickness to which the metal can be melted directly depends on the set current strength. The arc power is also determined by this indicator. The size of the electrode determines the required current strength.

Depending on the surface, the value of the welding current is selected. On horizontal surfaces it is maximum, on vertical surfaces it is less by about 15%, on overhanging surfaces it is 20%.

A household type welding machine can deliver up to 200 amperes. On the professional instrument values ​​go up to 250 or more. The direction in which the current flows will determine the polarity. On the inverter, it is possible to change the polarity.

As you know, the current moves from minus to plus. Therefore, the "+" terminal heats up more. This feature allows for high-quality metal welding. In the event that the parts to be welded are thick, then the positive terminal is connected to one of the parts. This method is called direct polarity.

A negative terminal is attached to thin products. This method connection is called reverse polarity.

Welding instruction

Welding basics

Before proceeding directly to the welding of metal products, you need to study the main design features of the inverter welding machine. They are shown in the diagram.

The inverter itself has average weight: up to 7-8 kg. A high-quality tool has a ventilation grill on the side of the metal case, which prevents the transformer from overheating.

There is an on/off button on the back panel. On the front there are two connectors: "+" and "-". A cable is connected to them, at one end of which there is an electrode, and at the other - a clamp. The cables themselves must be of sufficient length and flexible.

Step-by-step instruction telling how to cook with an inverter.

1. Inverter welding begins with the preparation of protective equipment. At your disposal is a welding mask, a thick jacket, rough but not rubber gloves.
2. Select an electrode. If you are a beginner, then do not use a rod thicker than 4 mm. On the front panel, adjust the right force current. Wait a little; If you bring the electrode directly to the metal, sticking will occur.
3. We fasten the clamp (it is also called the mass terminal) to the metal surface.
4. The arc is ignited. Then we bring the electrode to the metal and touch it a couple of times. Thus, the rod is, as it were, “activated”. The distance at which the electrode is held is usually equal to its diameter.
5. The rod during welding can move according to such schemes.

Arc ignition at the beginning of welding + (Video)

Striking the arc is the first step, and beginners have problems with it. First, the rod is tapped a little on the metal so that the grease is removed from it. Then a method similar to lighting a match is applied. The electrode is led over the surface of the product and slightly touches it. If suddenly the rod sticks to the metal, it is either sharply removed from the side, or the inverter is completely turned off.

You need to strike until a bright arc appears. To prevent the arc from disappearing, keep the electrode at a distance of 4 mm from the metal.

How to move the electrode during welding + (Video)

The electrode can only move along certain trajectories. They have already been shown. If you move the electrode only straight, the seam will come out discontinuous. The speed of its movement affects the properties of the seam. If you move quickly, the seam will be narrow and not convex, if slowly - wide and convex. In the place where the seam will end, the electrode is delayed for 3-4 seconds.

How to form a weld and avoid defects + (Video)

An uneven seam, most often, is formed when the electrode moves too fast. Speaking about creating an even and high-quality seam, you need to introduce the concept of a weld pool. The weld pool is that part of the metal that is in a liquid state during welding. Filler material enters this part. The appearance of a pool is a good sign that the welding is proceeding correctly.

The contour of the bath is located under the surface of the metal part. The bath forms a good seam if the welding arc passes evenly and to a great depth into the workpiece. It is necessary to ensure that the seam does not go down, but remains at the level of the surface. good connection it is easier to create if you make circular movements with the electrode. In this case, the bath should be distributed in a circle.

When seaming corners, remember that the tub moves with heat. Adjust the force of the arc to control the dimensions of the tubs.

The seam will not be too convex if you keep the electrode close to the vertical position. If you tilt the rod (for example, by 45˚), then the seam will begin to emerge. And when the electrode is very close to the horizontal position, the bath begins to diverge, and the seam is bent. Therefore, the optimal tilt angles are from 45˚ to 90˚.

Arc gap control

The arc gap is the distance between the metal surface and the electrode. The gap at each stage must be the same so that the welding is of high quality and without defects.

If the gap is small, then the weld will turn out to be too convex, and the material itself will not fuse well. This happens because the product cannot heat up. With a large gap, the welding arc will move from side to side, and the seam will come out crooked and fragile. The correct gap shown in the figure will give good penetration and a smooth seam.

How to weld thin metal sheets + (Video)

For welding thin metal, it is preferable to use the reverse connection of the inverter, i.e. "-" is attached to the sheet. In this case, the current strength should be at medium values. It is better to choose an electrode that will have long time melting. The MT-2 model is well suited. It is used by welders for a long time and therefore performed well.

The rod, in the case of thin metal, can be tilted by about 35˚. First, you carefully bring it closer to the metal, then wait for a red spot to appear, turning into a drop. Smoothly move the electrode so that the drop remains the same size. So the seam will be even.

There are an incredible amount of moments when it is required to weld by welding, and this may be required at home, in the country, in an apartment, in a garage, in any high-rise building, in particular, in such areas as construction or repair at home, as well as in plumbing, water supply and sanitation, and more. Hiring specialists to carry out welding work is not a cheap pleasure, and therefore many prefer to boil it themselves necessary elements. How to do it right? Learning how to work with electric welding from scratch is not easy, but it is quite possible, and for this you can attend classes for beginners, purchase a tutorial for dummies, or use the tips below.

To weld metal sheets or pipes, you will need to familiarize yourself with safety precautions, study the work process, carefully follow the technology, or hire a welder such as a trumpeter.

Many people think that it is enough to know how to use electrodes and how to weld seams, however, you need to know all the intricacies of the work, especially regarding the connection of 2 different metals and what kind of electrodes are needed.

Theory is one thing, but it takes a course of practice to start welding on your own various designs without errors and the possibility of leaks. For example, before welding, each element must be fixed with a coupler, clamps and other elements.

Need to know:

• What problems may arise;
• How to avoid defects;
• What is the welding technology of a particular type of elements.

In addition, tacks or, in other words, transverse seams may be required, each of which holds the joint of the joints, and it is advisable to install them at a distance of 10 cm from each other.

Weld Options

Exist different types seams, which may differ among themselves in various factors, in particular, in how the connection of metal products is carried out. These are the very basics of welding that beginners are taught.

The seam can be:

• Butt;
• overlap;
• Tavrovy.

The profession of an electric welder is very difficult and sometimes requires too much investment in strength and energy, since welding of metal products can be carried out even under the ceiling. The classification of the seam can be according to where they are located in space, and they distinguish vertical, horizontal, ceiling types.

Tips: how to learn how to cook with electric welding yourself

It is quite possible to weld a metal structure on your own in 1 day if you know how many electrodes are required, which ones you need to use, and provided that the product is not too large.

And what else you need to keep in mind to learn how to cook on your own:

1. It is important for a welder not only to work correctly, but also to learn the basics, in particular what mode of operation is required for a particular material, since the metal can be steel, alloys, or fabrics such as the color of met.
2. Be sure to study the methods by which you can make a specific seam.
3. It is necessary to correctly approach the choice of electrodes and welding wire.

If initially not required to become a professional the highest category, then you can learn welding yourself if you watch video tutorials, drawings with seams, and also study the advice of professionals. The training will be long, but possibly productive, especially if you gradually try to produce seams, increasing the amount of work experience.

To start welding, you need electrodes and the welding machine itself.

Many people prefer to use a resant, as the technique can withstand prolonged loads, which allows you to quickly bring the matter to an end. At the first try with welding, it is better to use a real inverter, and only then when great experience possibly any other device. With regards to the electrodes, it is advisable to choose "3". They are easy to use, and most importantly, they do not overload the electricity network.

In general, welding equipment is divided into types - transformer, rectifier, inverter. Why popularity remains behind inverters? They are compact, light weight, and very easy to handle for a beginner. At the first steps to learning welding, it is worth taking simpler types of metal and preferably even elements so as not to complicate the task.

Before welding, you need to prepare:

• Bucket with water;
• Hammer for churning slag;
• iron brush;
• A mask that protects the face and neck area;
• Gloves made of special fabric impregnated with a composition to prevent ignition and burnout of the canvas;
• Special clothes with long sleeves.

Do not forget that the welded business is a fire hazard, and therefore it is strictly forbidden to be near combustible or flammable objects in order to exclude serious consequences.

What defects should be aware of in order to make the correct welding seam

Making beautiful seams that look perfect is not so easy, since even a specialist with extensive experience cannot always carry out the process as competently as possible. It all depends not only on whether the rules are followed and whether the angle of inclination of the electrode is correctly chosen, but also on many other factors.

It is worth noting that any training manual has data on defects, which you must familiarize yourself with.

There are critical ones, and there are non-critical ones, that is, those that can be left without additional processing. We learn how to distinguish a high-quality seam from a poor-quality one and why defects occur.

Defects:

1. Lack of penetration is a defect in which insufficient filling of the joint space has taken place. liquid metal, this affects the strength of the connection. The reason may be a weak voltage, too high a speed with which the movement of the electrode is carried out. After the current is corrected and the arc shortened in length, the defect should be eliminated.
2. Undercut This defect indicates the presence of a groove running along the seam. The reason may again be too long an arc, due to which the seam is not just bad, but wide. This leads to incomplete heating of the metal, due to which the edges begin to harden quickly. To fix the problem, it is worth reducing the length of the arc and increasing the current.
3. Burn-throughs are through holes at the joints. The reason is a high current if the electrode is slowly driven, and too large gaps between the ends of the parts. The defect can be eliminated by correcting the welding mode.
4. If pores form on the seam, randomly scattered along the entire length of the joint, then this is due to the presence of a draft in the room, due to which the gas cloud is blown away from the work area, or if the metal is covered with rust.

There are other defects in the form of cracks, or the seam simply bursts, this occurs immediately after the metal has cooled. They can be longitudinal and transverse. Depending on when they formed, they are cold and hot.

Precautions before welding with electrodes

Regardless of where do-it-yourself manual electric arc camping welding is used, safety precautions must be observed, which every welding textbook displays.

Precautions:

1. It is strictly forbidden to use arc welding in the cold and in a room with high humidity.
2. A mask and a protective shield must be present, which will protect the eyes from burns.
3. Clothing should be with special impregnation, from which sparks and drops of hot metal will roll.

Hands should be covered with suede gloves or special canvas mittens. Due to the fact that welding work is carried out at high temperature, and the likelihood of fire is very high, the process should be carried out where there is water or a fire extinguisher nearby.

Nuances for beginners in welding

In the case of welding, there are many tips and even secrets for each master, but there are a number of general guidelines, guided by which, you can carry out work and put seams on almost professional level even when self-taught.

Nuances:

1. Be sure to remember about grounding, namely, there is a special clamp that must be tightly applied to the part.
2. Be sure to check the cable insulation and how carefully it is tucked into the part.
3. As soon as the masses are connected, the current strength is selected, it depends on the type of electrodes and on the material.
4. Before igniting the arc, you need to set the electrode relative to the material at an angle of 60ᵒ.

The principle of operation of welding and the scheme of work are not too complicated. Namely, if you start to slowly drive the electrode over the metal, sparks will begin to form, which indicates the formation of a welding arc. For it to arise, the electrode must be held so that the space between it and the canvas is 5 mm.

During operation, the electrode will burn out, but there is no need to rush to move it.

The speed with which you need to suture depends on what it should be: thin or thick. If the electrode sticks, simply move or tilt it to the side. The reception is simple but effective. It is worth noting that there is such a term as a weld pool, and it can have various sizes. For example, a width of 8-15 mm, a length of 10-30 mm, a depth of 6 mm.

The format depends on:

• Locations - indoors or in space;
• welding mode;
• Configurations of each connected part;
• The size and shape of the edge;
• Arc movement speeds.

Welding techniques can be used to make a boiler for heating or to connect water pipes. There are just a lot of places for using welding equipment, since it is used to build fences, make playgrounds, assemble metal structures of high-rise buildings, install drainage systems, install railings and more.

Having not only the skills to work with welding equipment, but also the appropriate education, you can equip your home or site with all the necessary facilities, as well as get a job prestigious job. Naturally, those welders who have a complete understanding of their work, welding modes, features and nuances of this business are held in high esteem.

How to cook with electric welding (video tutorials)

It is very easy to distinguish a beginner from a professional, as he will not be too hasty and will have to digest the seams more than once. If high-quality welding work is required, but there is not enough experience or knowledge, then it is better to entrust the process to professionals who are able to carry out everything on highest level while providing quality assurance.

Examples of welds (photo)

Manual arc welding with an inverter is one of the most accessible metal welding methods for learning. This requires a minimum of equipment, and budget steels are very cheap. But at the same time, manual welding with an inverter for beginner welders is more difficult compared to welding.