How to solder correctly with a soldering iron: soldering technique, tips and instructions for beginners. How to properly solder with a soldering iron using rosin How to solder small parts with a soldering iron

Let's say we need to solder aluminum - how? Not everyone knows that rosin only takes copper and its alloys. Everything else needs to be soldered using special fluxes, acids, and solders. Even steel lends itself to this science, if you approach it wisely. Let's see how to solder correctly with a soldering iron.

Process characteristics

Inside the soldering iron there is a heating element of a certain power. It is usually placed in an insulating jacket made of ceramic or other heat-resistant material. This is necessary so that all the heat goes inside where the sting is located. The main difference between soldering irons is power and shape. Depending on this, the master decides what exactly should be used.

You need to understand that this tool is often used in electronics. In this case, it is very important not to exceed the power dissipation of relatively fragile resistors, microcircuits, and capacitors. If this happens, then all the work must be redone. With the difference that you will have to buy the damaged element in the store. This is why it is so important to learn how to solder correctly.

It is difficult to say exactly what power will be required in this case. Usually radio amateurs focus on size.

Soldering iron power

First, the power of the soldering iron is assessed. It is clear that getting a 100 W unit into the motherboard is simply dangerous. To do this, it is wiser to purchase a 20 or at least 50 W soldering iron. Please note that not every soldering iron is powered from a 220 V network. There are many examples of non-compliance with this rule. The manufacturer is guided by simple logic: a low-power soldering iron requires a twisted spiral, which introduces large losses at a frequency of 50 Hz. Therefore, it is logical to switch to direct current. In this case, inductance no longer plays a big role. If you plug a low-power DC soldering iron (far right in the photo) into a 220 V AC network, the product will burn out. However, the Chinese produce quite small soldering irons (second from left). The one shown in the photo has a power of only 40 W and is powered from a standard outlet. Finally, by default, 100 W soldering irons were produced in the USSR (far left). The question arises - how to determine the power and supply voltage? This is the main difficulty because often the soldering iron does not have distinguishable symbols. If you take the Chinese one, then there is a red and white sticker on it (see photo) with information, and the one with a wooden handle has the power indicated on the plug. In addition, the protective casing of the 100-watt soldering iron is marked accordingly. Even GOST is indicated there, so you can glean a lot of information from the documentation. So, a powerful 100 W soldering iron allows you to work with rough and large parts, and is also indispensable for hard solders (but more on that below).

Section of the sting

Very often the size of the tip (metal rod for soldering) plays a role. For example, a 100-watt soldering iron has a solid copper stick. If you need to solder something thinner, then change the tip. It is with this particular soldering iron that you simply pull it out, but where to buy a spare one is another question. For example, stings are sold in special stores for radio amateurs and can cost a decent amount. For example, a Chinese 40 W soldering iron with an excellent tip cost 40 rubles (FixPrice), while a tip of this kind alone can cost 300 rubles separately. In this regard, you will have to think for yourself about what and where to buy. The fastening system is also different. For example, with a DC soldering iron it is unscrewed, but with a Chinese soldering iron it is held on with screws (like the one with a wooden handle). Moreover, the material itself may vary. Bulky tips of 100-watt soldering irons are usually made of copper, while more modest and miniature ones are made of an alloy of non-ferrous and ferrous metals. In any case, both of them allow you to work with all solders that can be melted.

Before work, the soldering iron tip is cleaned of waste materials and oxide film with a file or needle file. It is clear that this is not the only way. For example, dissimilar fluxes can be used for the same purposes. In this regard, we believe that it is time for readers to learn how a part is prepared for soldering.

How the surfaces of the part and the tips are prepared for the soldering process using fluxes

The surface of any metal (with some exceptions) is covered with an oxide film. As a result, the solder simply does not adhere. A group of substances whose purpose is to remove the oxide film from the surface are called fluxes. They come in solid and liquid forms, and are also sold mixed with solder in the form of pastes. The first category includes rosin and some other substances. Liquid fluxes are often acids or salt solutions. The base can be alcohol or other liquids.

It is important to understand that a different composition is used for each case. The only difference is the price, which you should try to save on. When exposed to high temperatures and rosin, the oxide layer is removed from the surface of the copper wire. In addition, varnish insulation, if any, dissolves (this is typical for transformer windings). At the same time, the flux improves the wettability of the surface. Due to this, the solder spreads without problems, and then sticks and hardens. This creates a moderately elastic, elastic and durable contact. That is why soldering is used not only by radio amateurs, but also by many other professions. Including car repairs.

So, for each type of surface, its own flux is sold. For example, steel is etched with hydrochloric acid, and zinc chloride is often used. It should be understood that after the soldering process the surface is cleaned, otherwise its destruction will continue. They get rid of flux residues with brushes, emery, and often wash the area of ​​acid action with a weak solution (5%) of soda, and then with hot and cold water.

Pay attention to wettability: to solder aluminum, it is not enough to clean off the top layer with a file. This does almost nothing, because the solder does not spread over the surface. Wetability is poor. After treatment with acid, the balance of power changes radically. As for steel, there are special acids for it (see photo). They even solder cast iron, cutting the edges for solder. First, the surface is treated with flux, after which it is tinned. Then gradually the entire volume is filled flush with the surrounding surface.

Ammonia is often confused with ammonia. The first is ammonium hydroxide (10% solution), and the second is chloride. Both cannot solder wires in their pure form, but they are used to make a wide variety of fluxes. For example, diluting ammonia with water produces hydrochloric acid. Here, over time, every amateur invents his own recipes, many of which can be read in the public domain. You can also solder aluminum with a soldering iron using an aspirin tablet.

What is solder and what types of solders are there?

Solder is a mixture of metals. The main task is to obtain maximum strength and electrical conductivity at minimal cost. Most often you have to deal with tin-lead solders, but zinc ones are also used for soldering aluminum. The melting point of the latter is higher, and this is one of the criteria by which it is customary to differentiate:

• Particularly fusible - melting point below 145 degrees Celsius.
• Low-melting - melting point above 145 degrees Celsius, but below 450.
• Medium melting - melting point above 450 degrees Celsius, but below 1100.
• High melting point - melting point above 1100 degrees Celsius, but below 1850.
• Refractory solders have a melting point above 1850 degrees Celsius.

You have to use the burner somewhere in the upper part of the third group. Because the melting point is too high for a soldering iron to handle. Let us add to this that the electrical conductivity of tin is higher than that of lead, for this reason compositions with a high metal content are more expensive for soldiers. But this is not the only reason. When tinning pots, it is very important to maintain conditions that are harmless to humans. It is clear that in this case there can be no talk of any lead.

The percentage of more expensive metals usually appears in the brand name. For example, in PIC (tin-lead solder) it can be 10, 60 or even 90%. In addition, the composition often includes antimony. Its percentage usually appears after a dash, for example, POSS 40-0.5. Antimony is added, like many other impurities, to improve the quality of the solder. In particular, it reduces oxidation of the melt, which leads to a better appearance, and there is no need to protect the joint with varnish. In addition, antimony increases the heat resistance of the compound to temperatures above 100 degrees Celsius.

In Europe, a ban on lead-containing solders is currently being introduced. They are replaced with silver ones, despite the fact that the melting point increases. And the cost increases, of course. But you shouldn’t think that a high price means indispensable quality. Tin is very expensive, but Scott's expedition to the South Pole was lost due to the tin plague in 1912. Strictly speaking, negative changes are possible already at a temperature of four degrees Celsius, but with a decrease the process becomes much worse. Imagine what happens to pure tin in the cold.

Strictly speaking, no one can fully explain the plague process. It is believed that the tin needs to be infected for this, and then the solder seams literally crumble. Scott's expedition took with it barrels of fuel, soldered with the purest metal. Studies have been conducted and it has been found that adding even a small percentage of lead blocks the development of plague. Even POS 90 is not afraid of frost, but is expensive, so POS 40 and lower are usually used in technology, despite its relatively low electrical conductivity.

It should be said that in addition to those listed, copper solders are used in some places. Their melting point is relatively high, so a torch must be used. In this case, flux is usually poured onto the surface (liquid is used less often) for cleaning. Then it all depends on the nature of the task. For example, to solder a cable tip, the first one is clamped in a vice with the bulb facing up, and solder crumbs are poured inside. All this is actively heated by the burner. The cable is then inserted inside, and its outer insulation is melted. It is recommended to cool the place forcibly, for example by blowing.

Soldering process

So, before starting work, you need to prepare a soldering iron. To do this, the sting is cleaned. Dense carbon deposits are removed by chipping with any sharp tool. The photo shows a soldering iron, part of the tip of which has been cleaned with a file. It can be seen that from long-term use the surface has become uneven and bumpy. All this interferes with the soldering process.

Light carbon deposits are removed after heating. For this, the same acids and even rosin are used. The task is to expose the sting. Sometimes, under the influence of fluxes, even a thick crust falls off, which is difficult to grind off.

The wire insulation is stripped to the required distance. The core is then treated with rosin melt or acid. In any case, this is done with a soldering iron, and in many cases a good fume hood will be required. For example, formic acid vapor is often used in industry, but this substance poses a great danger to humans. Therefore, before using any chemical to solder copper wires, carefully search the Internet to see what is said about the safety of such actions. The nature of the influence of formic acid makes your hair stand on end.

If you solder the wires correctly, then already in the process of removing the oxide film you will see how solder is creeping along the surface. This can be seen especially clearly on the reverse side of printed circuit boards. The tracks should be covered with a thin layer of solder. Those who think it will take a long time to worry needlessly worry. Literally, you need to go around the installation with smoking rosin in one fell swoop, and then pick up a little solder, and it will spread on its own over the surface. A typical power supply takes just minutes. Etching a board in copper sulfate takes much longer.

We believe that readers have already realized that soldering aluminum with tin is possible only after removing the oxide film.

To effectively join metal surfaces, it is best to resort to temperature effects. The simplest and most common method is soldering with a soldering iron. In this case, metal materials are joined under the influence of a local increase in temperature and welding at a lower temperature.

In order to correctly connect metal parts using a soldering iron, you need to know the main points that characterize the soldering process. To do this, it will be enough to read the article, watch the video lesson and try to master the technology in practice.

Soldering devices that produce heat are called soldering irons. Depending on the heating method, they are electric, gas, hot air, induction. Most often, electrical devices are used, the power of which is selected for soldering certain materials:

The most energy-intensive soldering irons include hammer devices, the power of which can reach up to 550 W. They can heat up to temperatures of 600C. Hammer soldering irons are used to connect massive parts.

Acoustic soldering iron Small in size, useful for electrical engineers. The device has a low heat capacity, so it is used for fine soldering work.

In addition to the massiveness of metal products, the required power of a soldering iron is influenced by the thermal conductivity of the material being processed. For example, for copper products the device should be heated much more than for working with steel parts.

The optimal required temperature of the tip of the soldering device can be maintained either manually or automatically. Thyristor regulators are used for this.

Preparation for the soldering process

Before starting work, you need to prepare a soldering iron, materials, tools and workplace.

Stand, on which the heated device will be located. On it you will need to place flux, “crocodile” and pieces of foam rubber, which are needed to clean the tip.

Tripod, on which will be placed: a holder for a soldering iron, a bath of rosin, clamps.

Preparing the soldering iron

Before working with a soldering iron, its tip is given a certain form. This is done using a file. The most used shapes are cut and corner. The knife type is used for soldering connector pins or several contacts of microcircuits.

The tip of the working tool should be evenly covered with solder. It will be difficult to solder with a “dirty” tip. Therefore, a cold soldering iron with a file must be cleaned down to the copper from which the tip is made.

After this, the device should be heated and sequentially touch the rosin and then the solder. This should be done several times, ensuring that the tip is evenly covered with solder. After this, you can begin to connect metal parts by soldering.

Flux preparation

Choosing the right flux is the solution to one of the important problems of soldering. It is necessary so that the soldered surfaces do not oxidize during heating. Otherwise, the joint will turn out unstable and loose. It can be damaged very easily. Therefore, the quality of the flux determines the difficulty or ease of the soldering process, and how firmly the material being processed will be connected.

Fluxes must be selected for the material prepared for soldering:

For connections of wires and microcircuits The widely known rosin is used. Externally, this crystalline transparent substance of a red-brown, red, yellow or orange hue is similar to amber.

For soldering hard-to-reach or inconveniently located parts Rosin-alcohol flux is used. To obtain it, rosin must be crushed to the state of sand and dissolved in denatured alcohol or technical alcohol. It is applied to the workpiece with a brush and stored in a tightly closed container.

For galvanized iron flux LK-2 is used, which consists of ammonium chloride, zinc chloride, ethyl alcohol and rosin.

For stainless steel phosphoric acid is used.

Prepare the surface well resistant metals active acid fluxes based on zinc chloride.

For steel soldering Soldering acids and aqueous solutions based on zinc chloride are considered effective fluxes.

You should know that for soldering stainless steels, more active fluxes are required than for processing low-alloy and carbon materials. Cast iron needs to be soldered with high-temperature soldering, so an electric soldering iron will not cope with it.

Soldering solders

Low-melting tin-lead alloys are used for electrical soldering and radio installation work. The most popular solders are POS-61, POS-50, POS-40, PSr-2, PSr-2.5.

It is very expensive to connect parts using pure tin, since it is a valuable material, so it is used quite rarely.

The best soldering quality is obtained after using solders that contain lead. However, this material is harmful.

To avoid holding hot solder in your hand while working, hold it with pliers or place it on a special device.

Before soldering, the surfaces of the parts to be processed are cleaned with sandpaper and degreased with gasoline or acetone. Then they need to be installed and secured in their original position. After this, you can warm up the soldering iron and start soldering in one of two main ways.

When applying solder to parts from a soldering iron, on the device you first need to melt a certain amount of solder, and then bring the tip to the connecting workpieces and press it. At this time, the flux should begin to boil and evaporate. At this time, use the tip of the device to distribute the solder along the joint.

When applying solder to the parts to be joined, first the workpieces themselves are heated using a soldering iron. Once they reach the required temperature, you will need to apply solder to the joint between the part and the soldering iron or onto the part. The melting solder will begin to fill the joint.

The choice of connection method depends on the nature of the work being performed. The first method is suitable for soldering small parts, and the second for connecting large products.

When working with a soldering iron, you must comply with some requirements:

1. It is good to warm up the device and the parts to be connected. If the solder smears and does not flow, then you need to increase the heating temperature of the soldering iron.
2. Residues of acid fluxes must be washed off after soldering. Otherwise, after some time the connection may be destroyed by corrosion. Alkaline substances can be used as a detergent.
3. Do not add too much solder during the soldering process. The seam should be slightly concave. Excess solder is removed by braiding or suction. If the tip of the device has acquired a metallic shine, then there is enough solder. The changed shape of the tip indicates that there is a lot of solder.

Quality junction should shine brightly. Burnt solder appears dull, but is acceptable in some cases. The spongy granular structure of the junction indicates insufficient temperature and an obvious defect.

At the preparatory stage, the wires should be stripped, twisted and tinned:

Solid wires Before soldering, they are cleaned to a shine. After this, they need to be dipped in rosin, connected, heated for a few seconds and solder applied. To ensure reliable insulation, a heat-shrinkable tube is placed on the exposed wire, which should be of a larger diameter. When exposed to high temperatures, it will shrink and form wire insulation.

Connecting wires by soldering is one of the effective methods that requires certain skills. Before connecting wires in this way, they must be properly prepared and tinned. This is required to ensure connection quality. After all, it is known that in a humid environment a process occurs in compounds . Oxidation leads to poor contact between wires and overheating of the connection. To avoid and achieve this, it is necessary to tin all stripped conductors, since in this case lead-tin solders are applied, which reduce the electromechanical potentials of the connected conductors (copper, aluminum).

Let's consider how to tin wires with a soldering iron. Once you figure it out, you will understand that this process is not at all complicated.

Necessary tool for tinning

To work you will need:

• A knife or special tool for stripping insulation from wires.
• Tweezers.
• Soldering iron (soldering station).
• Solder (tin).
• Flux (rosin or solder paste).

Instructions on how to tin wires

Let's look at how to tin wires step by step:

• First of all, the insulating layer is removed from the ends of the wires being connected. To do this, use a knife or a special tool to strip the insulation from the wires. The length of the cleaned section of the wire, depending on the specific situation, is 10-50 mm.
• Use the tip of a knife to clean the wire until it shines. This is necessary to remove the remaining insulating layer and oxides from the metal core. If the wire consists of many thin copper strands, before such stripping, the tip of the wire must be fluffed, giving it the appearance of a fan. After stripping, it is twisted into one core.
• The soldering iron is heating up. Before work, you need to make sure that the soldering iron tip is clean. If necessary, it is cleaned of oxides with a file or needle file and wiped on a wooden board.
• Next, the stripped sections of the wires are heated with a soldering iron.
• To distribute it evenly over the soldering iron tip, touch it to the rosin, then to a piece of solder. The sting is brought close to the wire that needs to be tinned. If the wire is sufficiently hot, the solder will be evenly distributed over the surface of the wire bundle.
• To increase the efficiency of the operation, you can lightly rub the sting along the wire from different sides. To protect against burns, the wire is held with tweezers or pliers.
• The melted rosin should envelop the entire contact surface of the wire. If the wire is thoroughly stripped, the tinning process occurs quite quickly.
• Make sure that the tip of the wire is covered with an even layer of solder. If the harness has poorly processed areas, the tinning procedure is repeated again.

One of the most reliable methods of connecting wires is soldering. This is a process in which the space between two conductors is filled with molten solder. In this case, the melting temperature of the solder must be lower than the melting temperature of the metals being connected. At home, soldering is most often used with a soldering iron - a small device powered by electricity. For normal operation, the power of the soldering iron must be at least 80-100 W.

What you need for soldering with a soldering iron

In addition to the soldering iron itself, you will need solders, rosin or fluxes; it is advisable to have a stand. While working, you may need a small file and small pliers.

Rosin and fluxes

To get a good connection between the wires, it is necessary to clean them of contaminants, including oxide film. While mono-cores can still be cleaned manually, multi-core conductors cannot be cleaned properly. They are usually treated with rosin or flux - active substances that dissolve contaminants, including oxide film.

Both rosin and fluxes work well, but fluxes are easier to use - you can dip a brush into the solution and quickly process the wires. You need to put a conductor in rosin, then heat it with a soldering iron so that the molten substance envelops the entire surface of the metal. The disadvantage of using fluxes is that if they remain on the wires (and they do), they gradually corrode the adjacent sheath. To prevent this from happening, all soldering areas must be treated - the remaining flux must be washed off with alcohol.

Rosin is considered a universal remedy, and fluxes can be selected depending on the metal you are going to solder. In the case of wires, this is copper or aluminum. For copper and aluminum wires, use LTI-120 flux or borax. A homemade flux made from rosin and denatured alcohol (1 to 5) works very well, and it’s also easy to make with your own hands. Add rosin to the alcohol (preferably dust or very small pieces of it) and shake until dissolved. Then this composition can be used to treat conductors and strands before soldering.

Solders for soldering copper wires with a soldering iron use POS 60, POS 50 or POS 40 - tin-lead. For aluminum, zinc-based compounds are more suitable. The most common are TsO-12 and P250A (made of tin and zinc), grade A (zinc and tin with the addition of copper), TsA-15 (zinc with aluminum).

It is very convenient to use solders that contain rosin (POS 61). In this case, there is no need to pre-treat each conductor in rosin separately. But for high-quality soldering, you must have a powerful soldering iron - 80-100 W, which can quickly heat the soldering area to the required temperatures.

Auxiliary materials

In order to properly solder wires with a soldering iron, you also need:

Alcohol may be required to wash off the flux, and electrical tape or heat-shrinkable tubes of various diameters for insulation. These are all the materials and tools without which soldering wires with a soldering iron is impossible.

Soldering process with an electric soldering iron

The entire technology of soldering wires with a soldering iron can be divided into several successive stages. All of them are repeated in a certain sequence:

That's all. In the same way, you can solder two or more wires, you can solder a wire to some contact pad (for example, when soldering headphones, you can solder the wire to a plug or to a pad on a headphone), etc.

After you have finished soldering the wires with a soldering iron and they have cooled down, the connection must be insulated. You can wrap electrical tape, put it on, and then heat up the heat shrink tube. When it comes to electrical wiring, it is usually recommended to first screw on a few turns of electrical tape, and then put a heat-shrinkable tube on top, which is heated.

Differences in technology when using flux

If active flux is used rather than rosin, the tinning process changes. The cleaned conductor is lubricated with the compound, and then heated with a soldering iron with a small amount of solder. Further everything is as described.

Soldering twists with flux - faster and easier

There are also differences when soldering twists with flux. In this case, you can not tin each wire, but twist it, then treat it with flux and immediately start soldering. The conductors don’t even need to be cleaned - the active compounds corrode the oxide film. But instead, you will have to wipe the soldering areas with alcohol to wash off the remnants of chemically aggressive substances.

Features of soldering stranded wires

The soldering technology described above is suitable for monocores. If the wire is multi-core, there are nuances: before tinning, the wires are untwisted so that everything can be dipped in rosin. When applying solder, you need to make sure that each wire is covered with a thin layer of solder. After cooling, the wires are twisted into one bundle again, then you can solder with a soldering iron as described above - dipping the tip into the solder, heating the soldering area and applying tin.

When tinning, multi-core wires must be “fluffed”

Is it possible to solder copper wire to aluminum

Aluminum cannot be combined directly with other chemically active metals. Since copper is a chemically active material, copper and aluminum are not joined or soldered. The point is too different thermal conductivity and different current conductivity. When current passes, aluminum heats up more and expands more. Copper heats up and expands much less. Constant expansion/constriction to varying degrees leads to the fact that even the best contact is broken, a non-conducting film is formed, and everything stops working. That's why copper and aluminum are not soldered.

If there is such a need to connect copper and aluminum conductors, make a bolted connection. Take a bolt with a suitable nut and three washers. At the ends of the connected wires, rings are formed according to the size of the bolt. Take a bolt, put on one washer, then a conductor, another washer - the next conductor, a third washer on top and secure everything with a nut.

There are several other ways to connect aluminum and copper lines, but soldering is not one of them. You can read about other methods, but bolted is the simplest and most reliable.

Every radio amateur or DIY repairman will sooner or later be forced to pick up a soldering iron and try it. The quality of the work performed and even the performance of the product will directly depend on many factors, which you must know about before starting work.

Proper use of a soldering iron

Despite the apparent simplicity of working with a soldering iron, it is very desirable to have initial skills in high-quality work and be able to correctly use solder with rosin.

Soldering is done using a variety of solders. The so-called solder in a rosin reel is perhaps the most popular. When performing work related to soldering, solder is used. The amount of tin and lead it contains is 60 and 40%, respectively. This alloy melts at 180 degrees.

What is needed to work with a soldering iron:

• the soldering iron itself;
• solder;
• rosin.

Heated solder will create a sufficient internal bond with metals such as copper, brass, silver, etc., if the following conditions are met:

• The surfaces of the parts must be cleaned of oxides.
• The part at the soldering site is heated above the melting point of the solder itself.
• During operation, the soldering area must be protected from exposure to oxygen; various fluxes are used for this purpose. They create a protective film directly above the soldering area.

Tricks and secrets of working with a soldering iron

After the solder has begun to melt, it can already be used for soldering. To do this, you need to cover the soldering iron tip with a thin layer of solder, and then wipe it thoroughly on a damp sponge. This is how the solder and rosin remaining from work are removed. It won’t hurt to get into the habit of wiping the tip with a wet sponge every time after soldering.

Before you start soldering a radio component, you need to prepare it. Its leads should be bent so that the part fits freely into the holes intended for it.

Beginners without experience often touch the soldering area with the tip of the soldering iron tip. And you need to hold the soldering iron so that the contact area between it and the place of soldering is as large as possible, otherwise the place where you need to solder does not heat up enough to hold the parts together.

How to clean a soldering iron tip

When soldering, carbon deposits often appear on the soldering iron. It can be removed with plain water. If you run a soldering iron over a damp cloth, the scale will remain on it, and the tip will become clean again. You need to do this periodically while working with a soldering iron. If the cloth doesn't help, you can use a stiff sponge.

Soldering tip classes

• The tips are removable and coated with nickel.
• Copper stings.

First-class soldering tips are usually used in complex soldering irons, in which it is possible to regulate the temperature.

The stings of the second are the most common.

Types of nickel-plated soldering tips

• A needle-shaped tip - they are used to solder very small radio components, such as SMD. When repairing phones, such a tip is indispensable. It is used on boards with a high density of mounted parts.
• Tip-spatula - used for desoldering and in cases of installation of large radio components. They work with multi-pin microcircuits.
• The tip is in the shape of a drop - it is convenient for them to transfer solder with rosin to the place of soldering, which leads to improved quality of work.
• A tip with a curved shape - most often it is used to solder radio components that are in a copper shell, so that no excess solder remains on the board. It can also be used for regular soldering. The soldering iron heats up to a temperature of 290-300 C.

When working with a soldering iron, you must always keep it perfectly clean. New soldering tips are usually hammered to create fine nicks on the surface. Subsequently, they are carefully trimmed with a file to give the tip the most correct shape.

Then the tip should be tinned using solder with rosin. That is, cover with a thin layer of solder, dipping it in rosin.

How to cool a soldering area

The metal tweezers used to hold the radio component also work as a heat sink during the soldering process. You can also use a special alligator clip for this purpose.

Secrets of soldering with a soldering iron

To obtain a good result when soldering, you must correctly use solder with rosin and flux. This is a low-melting alloy of a special metal that is used to solder the leads of parts and wires.

• The best solder is tin in its pure form. But such metal is too expensive to be used for soldering. Therefore, when working with radio components, so-called lead-tin solders are used.
• Lead with tin. In terms of soldering strength, these solders are no worse than pure tin. They melt at a temperature of 170-190 degrees. It is customary to denote such solders by the abbreviation “POS” - tin-lead solder. The number after these letters in the designation means the share of tin, expressed as a percentage. It is better to use POS-6O solder.

• Fluxes are substances that have antioxidant properties. They are used to prevent oxidation of the soldering area. If you don't use flux, the solder simply won't stick to the metal surface.

Types of fluxes

When working with radio components, fluxes that do not contain acid are used. For example, rosin. Bow rosin for lubricating musical instruments is also sold in stores. It can also be used for soldering. But metal utensils are soldered using solder without rosin. To repair it you will need zinc dissolved in hydrochloric acid. It is also impossible to solder radio components with such solder, since over time it will destroy the soldering.

If you need to solder in hard-to-reach places, you need to have liquid flux. You can make it yourself. Rosin is crushed into powder and poured into acetone or ethyl alcohol. After mixing the solution, you need to add more rosin until you obtain a thick, mushy mass. Such liquid rosin should be applied to soldering areas with a brush or stick. However, there is a nuance - to work with printed circuit boards, the flux must be more liquid. For hard-to-reach places, you can also use wire solder with rosin, which is much more convenient.

When working with various fluxes, it is necessary to take into account that those that contain acetone are very toxic. Therefore, when working with them, it is necessary to avoid getting vapors into the respiratory tract. It is better to solder near a window if it is summer, and in winter it is better to ventilate the room in which the work is being carried out. After finishing work, be sure to wash your hands with soap and warm water.

solder with rosin

An important condition for successful soldering is maintaining the cleanliness of the surfaces that need to be soldered. Be sure to clean the soldering areas until they shine. Then the parts need to be placed on a piece of rosin and warmed up. The melted rosin will help the solder spread evenly over the conductor or part that needs to be soldered. You can carefully rotate the part while moving the soldering iron tip over it so that the solder spreads in an even layer over the surface.

If you need to tin a conductor that is soldered into a board, then after cleaning the soldering area with sanding paper or a knife, you need to bring a piece of rosin, and then smoothly distribute the solder as evenly as possible, using a soldering iron.

The quality of soldering is also affected by how correctly the wires or contacts of the parts are connected during soldering. They should be pressed tightly together and then bring the soldering iron to the prepared conductors, touching it. After the heated solder has spread over the surface, filling even small gaps between them, the soldering iron should be removed.

Continuous soldering time should be no more than five seconds. After this period of time, the solder will harden and the parts will be firmly connected. However, to prevent the soldering from breaking, the parts should not be moved for 10-15 seconds after soldering is completed. Otherwise the connection will not be strong.

If work is done with transistors, then their terminals must be protected so as not to overheat. It is better to hold them either with pliers or tweezers, thereby dissipating heat.

When soldering radio components, you should never twist the ends of the parts. If you need to resolder parts or replace conductors, you need to think about this in advance, before starting installation. It is best to solder the ends of the parts at a short distance from each other, and not in one place.

Knowledge of how to solder correctly is needed not only by radio amateurs and electrical installation specialists. Every home handyman has to deal with the need for soldering when repairing electrical appliances.

Preparing the soldering iron for use

Before soldering with a soldering iron, you should properly prepare it for work. In everyday life, an electric soldering iron with a copper tip is most often used, which, during storage and use, gradually becomes covered with a layer of oxide and is subject to mechanical damage. To obtain a solder joint of good quality, the soldering iron is prepared for use in the following sequence:

1. Using a finely cut file, clean the working part of the tip to a length of 1 cm from the edge. After cleaning, the tool should acquire a reddish color, characteristic of copper, and a metallic luster. During stripping, the tip is given a wedge-shaped, beveled, cone-shaped shape in order to solder what the master needs.
2. Plug in the soldering iron and heat it to operating temperature.
3. The tip must be tinned and covered with a thin layer of tin - the same solder used to solder the connected conductors. To do this, the tip of the tool is immersed in rosin, and then a piece of solder is passed along it. You should not use a solder rod with rosin inside for tinning a soldering iron. To distribute the solder evenly, rub the working edges against a metal surface.

During operation, the half-plate will burn and wear off, so the soldering iron will have to be cleaned and tinned several times during the soldering process. You can clean the tip with a piece of sandpaper.

If the master uses a tool with a nickel-plated, non-burnable rod, it will have to be cleaned with a special sponge or damp cloth. They tin such a sting in molten rosin, running a piece of solder over it.

Soldering can only be learned on the job, but before that it is advisable to become familiar with the basic operations.

Fluxing or tinning

The traditional and most affordable flux is rosin. If desired, you can solder with a solid substance or its alcohol solution (SKF, Rosin-gel, etc.), as well as TAGS flux.

The legs of radio components or chips are covered with half-milk at the factory. But to get rid of oxides, you can tin them again before installation, lubricating them with liquid flux and covering them with an even layer of molten solder.

Before processing with flux or tinning, copper wire is cleaned with fine emery cloth. This removes the oxide layer or enamel insulation. Liquid flux is applied with a brush, and then the soldering area is heated with a soldering iron and covered with a thin layer of tin. Tinning in solid rosin is done as follows:

• melt a piece of the substance on a stand and heat the conductor in it;
• feed the solder rod and distribute the molten metal evenly over the wire.

Correctly soldering massive copper, bronze or steel parts should be done using active fluxes that contain acids (F-34A, Glycerin-hydrazine, etc.). They will help create an even layer of poluda and firmly connect parts of large objects. Tin is applied to large surfaces with a soldering iron, spreading solder evenly over them. After working with active flux, acid residues should be neutralized with an alkaline solution (for example, soda).

Preheating and temperature selection

It is difficult for beginners to determine at what temperature the tool can start working. The degree of heating should be selected depending on the type of material:

• soldering microcircuits requires heating no higher than +250°C, otherwise the parts may be damaged;
• large individual radio components can withstand heating up to +300°C;
• Tinning and joining of copper wire can occur at +400°C or slightly lower;
• massive parts can be heated at the maximum power of the soldering iron (about +400°C).

Many models of instruments have a thermostat, and it is easy to determine the degree of heating. But in the absence of a sensor, it is worth keeping in mind that a household soldering iron can be heated to a maximum of +350... +400°C. You can start working with the tool if the rosin and solder melt within 1-2 seconds. Most POS grade solders have a melting point of about +250°C.

Even an experienced craftsman will not be able to solder correctly with a soldering iron that is not heated enough. With low heat, the solder structure becomes spongy or granular after solidification. Soldering does not have sufficient strength and does not ensure good contact between the parts, and such work is considered a defect.

Working with solder

When heated sufficiently, the molten solder should become flowable. For small jobs, you can take a drop of alloy on the tip of the tool and transfer it to the parts to be joined. But it is more convenient to use thin wire (rod) of different sections. Often inside the wire there is a layer of rosin, which helps to properly solder with a soldering iron without distraction from the process.

With this method, a hot tool heats the surface of the connected conductors or parts. The end of the solder rod is brought to the tip and pushed a little (1-3 mm) under it. The metal instantly melts, after which the remainder of the rod is removed, and the solder is heated with a soldering iron until it acquires a bright shine.

When working with radio components, you need to take into account that heating is dangerous for them. All operations are performed within 1-2 seconds.

When soldering connections of single-core wires of large cross-section, you can use a thick rod. When the tool is heated sufficiently, it also melts quickly, but you can distribute it over the surfaces to be soldered more slowly, trying to fill all the grooves of the twist.

The ability to solder in modern life, saturated with electrical appliances and electronics, is as necessary as the ability to use a screwdriver. There are many methods for soldering metals, but first of all you need to know how to solder correctly with a soldering iron. This seemingly simple action has a lot of subtleties and nuances - starting with the choice of tool and ending with safety measures when working with it.

General issues

Metals are used; they tend to spread over the surface if they are in molten form. This is facilitated by the forces of gravity and moderate tension. This property allows you to connect multiple parts. They are covered with a layer of solder, fixing the elements in a certain position.

It would seem that everything is elementary: I melted the metal and covered the place where the parts were attached. In practice, a more complex situation is observed, because it is important that the part is both durable and conductive of electric current. Ideally, the layer should be thin, but with maximum coverage.

To better spr When performing this operation, you need to consider the following points:

The ability to do this correctly is the key to success. Everything is not so complicated, because there are many universal options with which you can easily solve most current soldering problems. All the necessary information is contained on the labels, so before purchasing any brand, carefully read what is written there.

Typically, fluxes are needed for etching and removing the oxide film. In addition, their use is an excellent way to protect against corrosion. Without them, it is difficult to imagine complete preparation for soldering, because if the parts are not tinned, then high-quality joints will not be achieved. As a rule, these substances are mixtures of salts, alkalis and acids.

There are two types of fluxes:

The choice is made based on the specific goals to be achieved. It is better to have both varieties in your arsenal.

Fixation is carried out using solders. As a rule, lead-tin grades (PLS) are used. After the marking there must be a number indicating the concentration of tin. The more impressive this indicator, the higher the resistance to mechanical stress and electrical conductivity. The melting point is lower. The lead in the compound is needed for hardening. Without it, tin will not be able to maintain its uniformity.

There are special types of solders on sale that do not contain lead (BP). It is replaced by indium or zinc. The big advantage of such compounds is the lack of toxicity. The melting point is higher, but the strength is much greater.

You can find low-melting grades. These are Wood and Rose solders. They spread at a temperature of 90−110 degrees. Such connections are used when creating and repairing equipment.

The variety of types of work and the conditions in which they are performed has given rise to several types soldering equipment.

Selecting a soldering iron tip

This part of the structure varies in shape and material from which it is made. The most primitive option is the awl-shaped sting. There are many variations: blade, cone, bevel, etc. When choosing a shape, you need to have an idea of ​​the work that will be performed by this tip. It is important to purchase something that will provide the maximum area of ​​contact with the surface.

Typically the material used is copper, to which various impurities are added (for example, chromium or nickel). This allows for improved performance properties. In particular, durability is significantly increased.

A tip without a coating quickly becomes unusable. It has to be cleaned periodically and tinker. To level out this flaw, it is recommended to forge this element and grind it to give it one shape or another.

In various situations, this tool can be used with a number of features that are worth paying attention to. Not only the final quality, but also the degree of feasibility of the operation as a whole depends on this.

Soldering wiring

The ends are dipped in flux and then passed over them with a tip moistened with the same solution. It is important to shake off excess wires. Don't neglect this if you want to achieve a quality connection and flawless functioning.

When the preliminary stage is completed, we twist the wires and warm them up with a small amount of solder. All free space must be filled with the molten mixture.

If multi-wire conductors are involved, you can do without tinning. The ends are simply wetted and fixed without pre-treatment with a sting. This operation is not performed inside switchboards, as the risk of corrosion is high. In addition, such structures do not belong to the detachable category.

Electronics repair

Correct approach can only be achieved experimentally. If you have never done such work, use the help of a specialist who will tell you how to how to use a soldering iron in this case, it is important that someone controls and deposits on time edits into the process. But if we are talking about standard printed microcircuit, even those who picked up the instrument for the first time can handle it.

Easiest to solder small output elements. We first fix them with some viscous substance in the holes. Press the tip tightly on the back side to warm it up. Then we introduce solder into the soldering area (there should not be too much of it).

If the output element is loose, first moisten it with flux. With this technique, a small drop of tin is transferred from the soldering iron to the leg. The substance flows down, filling the hole.

Large parts

Cable sleeves, tanks and dishes have a high heat capacity, so the process service and the connections look a little different.

First, we achieve complete immobility. This is done using clamps or plasticine (wax). Then spot welding is performed.

Next stage - tinning. It is performed at the fixation sites. It is important to approach this process with the utmost care.

Then the free space is filled with solder. Special compounds are used that are characterized by their refractoriness and the ability to maintain tightness over a long period of time.

If you have to make a large seam, the role of a soldering iron can be played by a copper hatchet heated over a fire. This is all, what is needed for soldering in such cases.

Important points

Working with a soldering iron is not as simple as it might seem. The development of this skill will significantly expand the range of operations and technician, which you can use.

What do we need for soldering? Of course, a soldering iron (ideally a soldering station), tin solder, rosin, ideally solder wire, which is a long, thin tin tube wound on a reel, similar to a wire, in the cavity of which there is rosin. Those. when soldering, in this case, we do not need, as in the old fashioned way, to lower the tip of the soldering iron, now into the rosin, now into the solder, but all this happens simultaneously at one point. More on this below...

You can purchase all the necessary components at your nearest radio store.

If you do not have a soldering station, which is initially ready for soldering immediately after switching on, but a regular soldering iron, then before work (especially if it is new) you need to prepare it in a special way - tin it, otherwise it will not solder. Now let’s look at what “tinning” means.

How to tin a soldering iron?

Take a file and apply it flat to the cut of the soldering iron tip. Now we sharpen in the same plane, periodically looking at the tip, until it becomes flat, smooth and shiny.

After this, we lower the heated tip into rosin and immediately into solder (into tin). There will be almost no solder sticking to the tip, so immediately after this procedure we apply the tip to a small board, preferably of natural origin (not chipboard), preferably spruce or cedar (resinous), but in principle, any will do, you’ll just have to mess around longer.

So, we repeat this procedure (rosin > solder > board) until the cut of the tip, prepared in advance with a file, made of yellow - with a bluish tint of heated copper, becomes silvery and shiny from the solder evenly covering it. This is what is called “tinning”, in this case a soldering iron.

This is what a tinned soldering iron tip should look like:

Now we will learn to solder wires (after tinning it) to a brass tin, also tinning it from the beginning. We dip the soldering iron tip into rosin, then into solder, and immediately, with the plane of the tip parallel to the plane, we bring it close to our brass test subject, without allowing the rosin to evaporate, we press it, then we rub it in, we grind, in general, we tin. If the rosin has evaporated or spread, we repeat the process, and gradually, gradually our tin is covered with high-quality solder adhering to it. If the material is clean or without strong oxides, then such tinning occurs quickly.

If solder wire is used, then we lean the tip of the soldering iron against the tin, and bring the tip of the solder wire to the point of contact, trying to touch more of the tinned part of the soldering iron, and rub it against this part so that the tin and rosin enrich the contact point.

How to tin a wire?

Now let's tinker with the wiring. We carefully remove the insulation just enough so that we have enough space for soldering, and for the location of the heat-shrinkable tube (or other insulator) so that later no short circuits (short circuits) arise...

It is easier to tin the wire, because Usually, the metal under the insulation is clean, not oxidized. We dip it in rosin, placing the tip of a heated soldering iron on top of it and slowly pull the wire out from under the soldering iron after the rosin melts and starts smoking. This is done, as you probably understood, so that the molten rosin envelops the contact part of the wire. Now we enrich the soldering iron tip with solder, touching the tin, and bring the tip to the rosin adhering to the wiring.

If the wire is copper and clean, tinning will occur immediately.

How to solder a wire?

We have a tinned experimental brass tin and a tinned wire, which we now have to connect, seal with heated solder and then cool in order to forever maintain their electrical connection, which we do by bringing the tinned part of the wire to the tinned part of the tin.

We bring the soldering iron tip enriched with solder to the place of their contact so that the solder covers the tinned parts of the soldered parts well. This will be facilitated by the rosin involved in the process. If something doesn't go well, dip into it. Once the parts are in the molten solder, try not to move them anymore. You can lightly blow on the solder area until the shine of the solder darkens slightly, indicating that the solder has hardened.

And probably the final touch - you can also dip a small paint brush into the solvent and wash off the remaining rosin in the soldering areas.

Soldering is a technological operation that makes it possible to obtain a permanent connection of elements from different materials, which is ensured by the introduction of solder with a relatively low melting temperature.

There are several rules that explain how to solder correctly and get good results when working with such a tool.

Hand tools used in tinning and soldering allow the parts and flux to be heated, and also melt the solder and then apply it to the contact areas of the elements being soldered.

The main types of soldering irons are represented by several designs:

• A tool with a nichrome heater in the form of a wire spiral that passes alternating mains or direct/alternating current values ​​of low voltage.
• Modern models are distinguished by temperature control of the tip heating using a built-in temperature sensor. The design of the device can be supplemented with special insulators that reduce heat loss and increase heat transfer.
• A tool with a ceramic rod heater that is triggered when voltage is applied to the contact group. This type belongs to the category of the most advanced devices, characterized by fast heating and a long service life, as well as having a wide range of temperature and power level control.
• Induction tool carries out heating through the coil part of the inductor, and the tip is characterized by the presence of a ferromagnetic coating, which contributes to the production of a magnetic field and heating of the core. Maintaining the required temperature on the tip is carried out automatically and does not require a temperature sensor or any control electronic device.
• Impulse tool It works by pressing and holding the special “Start” button in this position, which is responsible for the almost instantaneous heating of the tip to optimal operating temperature values. Domestic designs of this type are characterized by the presence of a circuit in which the copper wire tip is part of an electrical circuit that also contains a frequency converter and a high-frequency transformer. The most modern pulse models have power and temperature control, which allows you to equally successfully solder small electronic elements and fairly large parts.
• Gas tool belongs to the category of practical and autonomous devices, and the combustible gas with which the device is refilled serves as a heat source for sufficient heating of the tip. The absence of a nozzle allows this type of soldering iron to be used as a traditional gas burner.

Self-contained cordless tool

Of course, a large hot-air and infrared soldering tool cannot be regarded as a worthy competitor to traditional household electric soldering irons, but it has many advantages of use:

• heating of the soldering area is carried out by means of a hot air jet, which is ejected by the nozzle of the soldering station;
• the standard temperature regime of focused air heating is about 100-500 °C;
• Depending on the type of air pressure, the devices can be represented by turbine and compressor stations.

In infrared soldering stations, heating is carried out under the influence of infrared radiation at a wavelength in the range of 2-10 microns.

The old soldering irons, which were popular until recently and heated over a regular open fire, are no longer necessary today, however, a simple DIY design can sometimes serve as a replacement for expensive equipment.

Types of solders and fluxes

Solders are materials used in soldering and having a melting temperature lower than those of the metals being joined. For this purpose, tin, lead, cadmium, copper, nickel, silver and some other types of alloys are used:

• soft solders with a melting temperature within 300 °C are represented by tin-lead alloys, antimony solders for soldering galvanized or zinc elements, tin-lead-cadmium solders for soldering products that are ultra-sensitive to overheating, tin-zinc and lead-free solders;
• Hard solders with a melting temperature above 300 °C are usually represented by copper-zinc, copper-phosphorus and silver solders with different types of additives.

Fluxes are organic and inorganic substances or mixtures that allow the removal of oxides from the surface being soldered, protecting it from the negative effects of the external environment and actively reducing surface tension, as well as significantly improving the spread of liquid solder:

• depending on the temperature range of activity, all mixtures and substances are represented by low-temperature and high-temperature fluxes;
• Depending on the nature of the solvent, the fluxes used are aqueous and non-aqueous;
• depending on the nature of the activator that determines the action, fluxes can be acidic, rosin and halide, hydrazine and fluoroborate, aniline and stearic, as well as boride-carbon dioxide;
• depending on the mechanism of action, fluxes perform protective or chemical functions, have an electrochemical and reactive effect;
• Depending on the state of aggregation, solid, liquid and paste-type fluxes are used in soldering.

The simplest and cheapest type of flux that has a low leakage current is pine rosin.

This chemically passive type of flux is very widely used and has moderate solubility in alcohols with glycerin.

Auxiliary materials

The most famous, high-quality and popular, but quite expensive fluxes of foreign origin include IF-8001 Interflux, IF-8300 BGA Interflux, IF-9007 Interflux BGA and FMKANC32-005.

• Auxiliary materials are represented by components that are not directly included in the solder joints being formed, but take part in its formation:
• soldering fluxes - auxiliary materials that remove oxides from the surface of soldered materials and solder, as well as prevent their formation;
• stop pastes and stop coatings are auxiliary materials used to prepare the surface of structural elements and applied to soldered areas where the use of liquid solder is undesirable;

solders are auxiliary materials represented by special refractory or low-melting alloys, which depends on the metals included in the composition.

Synthetic adhesives and acetones, most often used in electrical installation work, are fire hazardous and harmful auxiliary substances, so their use will require strict compliance with fire safety and sanitary standards.

The main auxiliary materials for soldering are represented by solders and fluxes, as well as gaseous media that facilitate the application of stop materials to coatings.

Soldering temperature

The temperature regime of soldering is one of the most important points when a solder performs work, and has a direct impact on the quality of metal joints. Moreover, this indicator should exceed similar indicators of complete tinol melting.	Type of solder used			Chemical composition
	Melting temperature	Zinc	Copper
Silver	64	36	–	PMC-36
825 o C	37	53	10	PSr-10
830 o C	25	30	45	PSr-45
730 o C	46	54	–	PMC-54
880 o C	35	40	25	PSr-25
780 o C	4	26	70	PSr-25

According to the theory of the work being carried out, before the gap is filled and distributed in all joints, the solder must completely melt, therefore the temperature regime of the tinol liquidus is the lowest used for high-temperature soldering. At the same time, all soldered elements must heat up more strongly.

Preparing the soldering iron for use

The first connection of a new soldering iron to the electrical network is accompanied by the release of smoke from the body, which is caused by the burnout of varnish and fats that got into the tool during the assembly or preservation process. It is for this reason that the first switching on is carried out in well-ventilated rooms or outdoors.

The tip of the purchased soldering iron must be given an optimal and convenient shape using a soldering iron, so its end is heated and forged. As a result of this simple procedure, maximum compaction of the copper occurs and the overall service life of the tool is extended.

The most commonly used and universal ones are the angular tip and the “cut” one, and the knife-shaped form is used somewhat less frequently in work.

Preparing parts for soldering

Cleaning of contaminated surfaces is carried out using mechanical or chemical methods:

• the first option involves cleaning the surface with a file, a metal brush, a grinding wheel or sandpaper, as well as the use of sandblasting machines followed by blowing with a stream of compressed air;
• the second option is based on removing grease, rust and scale with gasoline, trichlorethylene and various alkalis with mandatory subsequent rinsing under hot and cold water.

Scale and rust must be removed by etching with a sulfuric acid solution, after which the product is washed and flux is applied to hard-to-reach areas. Soldering complex assemblies involves fixing them using studs, bolts or special devices.

Surfaces that should not have solder after soldering must be coated with a graphite or chalk-based aqueous paste.

Tinning

If there is no special protective coating on the soldering iron tip, the process of tinning or covering it with a thin tin layer is mandatory. For this purpose, the soldering iron tip is brought to operating temperature, after which it is dipped in rosin, and the completely molten solder is carefully and thoroughly rubbed over the surface of the tip. You can also moisten a piece of cloth in a solution based on zinc chloride and wipe it on a heated soldering tip, then rub a mixture of molten solder and rock salt into the surface.

The process of tinning a new soldering iron

Tinning allows you to protect the device from corrosive changes and unreasonably rapid wear, therefore it is performed during the first turn on of the tool after the smoke ceases to be emitted.

Soldering technique with a soldering iron

There are several main methods of soldering using a soldering iron, which differ in technological solution:

• low-temperature soldering can be carried out manually and semi-automatically, using a wave of liquid solder or by immersion in a container filled with molten solder;
• high-temperature soldering is performed using gas torches and high-frequency currents, as well as in the process of exothermic work.

Different types of soldering irons

The main stages of soldering include preparing the parts, fluxing or tinning, heating the parts to be soldered, and carefully applying solder to the soldering area. The so-called soldering without the use of solder is quite in demand. For example, soldering titanium and copper does not require auxiliary materials, but is based on a phenomenon such as contact melting.

Cold soldering is a defect and is characterized by the lack of formation of a strong solder joint, therefore it has a grainy structure and dull color.

Soldering with rosin

Colophon resin, a brittle and glassy amorphous substance of dark red or light yellow color, is widely used as a flux.

The simplest is SKF, or alcohol-rosin flux, which is as easy as possible to use.

The heated soldering iron is lowered into rosin and covered with solder, which is applied to the surfaces to be soldered.

The parts installed in the desired position are soldered while working with them using a soldering tip coated with solder and rosin.

Soldering with acid

Phosphoric acid is often used in soldering as a flux to join carbon or low-alloy steels, nickel and copper alloys. The mechanism of action is the dissolution of the metal oxide film, solder and further loosening with the flux floating to the surface.

The use of phosphoric acid is preferred when joining more complex materials than silver and copper.

Soldering safety precautions

When using a soldering tool, measures are taken to prevent injury from electric current and gas mixtures, molten salts and metals.

The use of induction soldering requires compliance with safety rules when operating any electrothermal devices.

During the soldering process, special means for individual protection of the eyes, respiratory system and skin must be used.

Working with explosive and fire-hazardous auxiliary materials requires particularly strict adherence to safety precautions.

Conclusion

Soldering is a popular and absolutely safe process only if all relevant technological rules and certain precautions are observed. To obtain high-quality soldering, it is important not only to choose the right tool and auxiliary materials, but also to take into account the operating principle of the soldering iron and methods of preparing surfaces.