As with other work, soldering parts has its own secrets and features. Some people think: everything is simple - turn on the soldering iron, take solder, rosin and solder as much as you like!

But if you look at everything in order, it turns out that it is not so simple. Knowing how to solder correctly is a kind of art and experience comes with time. In order to solder well and efficiently, you need to know some basic soldering secrets, which will be discussed in this article.

Good soldering iron

Of course the first thing you need is soldering iron. There are many different cheap soldering irons on the market today. Most of them operate from a ~ 220V network and do not control the heating temperature of the tip. On more expensive ones there is a regulator, when the soldering iron gets hot, the voltage decreases and the temperature of the soldering iron is maintained the same.

There are many circuits for regulating the temperature of a soldering iron, so you can use a simple regular soldering iron through a voltage regulation circuit.

One of the secrets of high-quality soldering is cleanliness of the soldering iron tip and its heating. If the tip is dirty, it will be difficult for them to work - the solder will melt, but will not stick to the surface of the tip. The tip must be cleaned and tinned - covered with a thin layer of solder. They do it like this. Warm up the soldering iron and clean its tip with a file or sandpaper. Dip the tip into the rosin and then touch it to a piece of solder. In a layer of molten solder, move the tip along a wooden stick (or along a stand) so that its entire surface is covered with a layer of solder. Over time, the tip will become covered with a dark oxide coating, which interferes with soldering. Then tin him again.

For fine work, you need a soldering iron with a thin tip, especially if you are working with surface-mounted SMD components.

Usually a soldering iron with a power of 30 to 40 W is enough for general work. You should hold the soldering iron while soldering for about 3 - 4 seconds to avoid overheating of the radio elements.

Additional tools and accessories

Besides the soldering iron, there are a few other things that I consider necessary for good soldering. Of course, one of which is solder. Solder is a low-melting metal alloy that is used to solder wires and leads of parts. For radio installation, tin-lead solders, which are an alloy of tin and lead, are more often used. The melting point of solder is 180 - 200 ° C. They are designated by three letters - POS (tin-lead solder), for example: POS-40, POS-60 numbers are the tin content as a percentage. I prefer POS-60 (60/40) solder - this is the most common solder. It is composed of 60% tin and 40% lead with flux in the center of the solder.

Fluxes- These are antioxidant substances. They are used to ensure that parts or conductors prepared for soldering do not oxidize during soldering. Without flux, solder may not stick to the metal surface. Solder comes in a variety of diameters and you can use whichever you prefer depending on what you are soldering. Personally, I like the thin 0.56mm stuff for most jobs. To be able to solder in hard-to-reach places, it’s a good idea to stock up on the liquid flux mentioned above. You can prepare the flux yourself: to do this, grind rosin into powder and pour it into boric alcohol or glycerin. While stirring the solution with a stick, add rosin until a thick paste is obtained. This rosin is applied to the soldered areas with a thin stick or brush.

Be sure to follow safety rules when working with solder: wash your hands after soldering warm water with soap, do not inhale the steam from the melted solder! This rule applies to all types of solder!

Remember that soldering releases harmful tin and lead fumes. Under no circumstances should you lean over the soldering area and inhale fumes. In summer, try to solder near an open window; in winter, ventilate the room more often. It would be nice to have a hood above the workplace!

Soldering iron holder

You should have a convenient holder for your soldering iron. There are stands along with cleaning the soldering iron tip.

Another tool I use often is a vacuum solder sucker. I believe this is one of the inexpensive and the best ways release the part from the solder.

Of course, there are other things that will help with soldering, such as a well-lit work area, snap-on tweezers, etc. I have some grooves and holes drilled into a piece of wood to allow for example a potentiometer shaft to be pressed down and held while soldering, and also for soldering wires etc.

For example, I solder a part and then cut off their protruding leads. Of course, some will first cut to size and then solder the parts, and this may look neater and more convenient. But I think trimming after soldering is faster and easier. Use good sharp nippers for this so as not to damage the tracks.

If you are soldering radio components that are sensitive to overheating, use a heat sink. This could be regular tweezers, duckbills, or pliers. Hold the leg of the radio component while soldering. If you need to solder the ends of two tinned conductors, press them tightly together and apply a soldering iron with a drop of solder at the end of the tip to the point of contact. As soon as the soldering area warms up, the solder will spread and fill the gaps between the conductors. Using a smooth movement of the soldering iron, distribute the solder evenly over the entire soldering area. The duration of soldering should not exceed 3-5 s, especially for radio components that are sensitive to overheating (transistors, microcircuits, diodes, zener diodes...) after which the soldering iron is removed. The solder will quickly harden and firmly hold the parts together; at this time, you must ensure that the parts or conductors do not move for 10 s. To speed up the cooling, you can blow, at the same time we will blow the solder fumes away from us.

Board mounting features

During the installation of structures, it is necessary to resolder conductors or replace parts. This must be taken into account during installation. Thus, the ends of parts connected according to the diagram with a common conductor should be soldered not at one point, but at some distance from each other. It is not recommended to twist the ends of the parts around the conductor.

If you are making a board with a large number of components, first think about the order so that all the radio components fit on it. Consider the size of the parts as well as the heat generated during operation. Do not place other components, especially electrolytic capacitors, close to heated radio elements. If necessary, leave space for the radiator.

Soldering wires

If you are soldering a stranded wire, first remove the required piece of insulation from it, twist the wire strands, and then tin the solder.

If you will be tinning varnished wire (PEL, PEV), clean this area with sandpaper or a pocket knife and apply a piece of rosin. Using a smooth movement of the soldering iron, distribute the solder evenly over the surface to be tinned.

Places of conductors and parts intended for soldering must be cleaned to a shine. The thoroughly stripped conductor is placed on a piece of rosin and heated well with a soldering iron. The rosin will quickly melt, and the solder on the soldering iron will spread over the conductor. By turning the conductor and slowly moving the soldering iron tip along it, achieve uniform distribution of solder over the surface of the conductor.

I could add a few more tips, but I hope that you found something useful for yourself and will soon give useful tips for beginners. 🙂

Now pick up a soldering iron and make your dreams come true, impress your friends with your interesting electronic DIY projects!

Zotov A., Volgograd region.

P O P U L A R N O E:

What is a radio receiver? A radio receiver is a device for receiving electromagnetic waves with subsequent conversion (demodulation) of the information contained in them, which can then be used.

Circuits for radio receivers on microcircuits look more attractive - they are easier to manufacture compared to circuits on transistors and have better technical characteristics.

Soldering requires some skill, but the process is not particularly difficult. This is why many are interested in how to properly solder microcircuits. Exposing various metal structures to temperature to hold them together is the most effective technology. Bonding metal workpieces using a local increase in temperature and surfacing at a lower temperature is soldering. This process is most similar to the surface connection of structures that are melted.

The soldering station allows you to set the temperature with an accuracy of 1°C.

How to choose a soldering iron?

A soldering iron is a soldering device that is capable of emitting heat. Such designs can have a power from 15 to 30 W. With their help you can solder blanks of various boards and microcircuits. Tools that have more power are used exclusively for soldering an XLR connector or re-soldering a joint of thick wires.

For an electrical engineer who works with office equipment, an acoustic soldering iron will be a useful tool. Such a device is characterized by low heat capacity, small dimensions and excellent performance. The device can be used to perform fine soldering (for example, assembling various schemes). You can also find professional soldering irons of large sizes on sale, which in most cases are used to connect cables for calibration. Using similar products you can also perform stained glass work.

The soldering iron must have a grounding plug with three guides. Such a device allows you to prevent voltage dissipation along the path of current passage in the structure. Heat will be generated by closing the current in the tip, which is made of steel wire. For a novice electrical engineer, a device with a range of 15-30 W is suitable, but one should take into account the fact that a device with a power of 15 W may not be enough to secure even ordinary audio wires. If you plan to work in a car, it is recommended to purchase a 40 W design, which can cover large areas and provide a fast connection. For cars, in most cases, additional attachments are purchased to make the soldering process easier.

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Using a soldering station

Before starting work, remember correct location chips: the key (circled in red) should be located near the beveled corner of the square.

In order to ensure autonomy, you will need to use a soldering station. This design is a device in which the machine is connected to an alternating current source. This device can emit power up to 80 W. Working with the design may require a little experience, but experts believe that soldering is much easier with such a device.

The main advantages of soldering installations are the following:

1. It is possible to control the temperature with an accuracy of 1°C.
2. Such a device is capable of soldering even complex workpieces made of aluminum, of stainless steel, ordinary steel and other materials.
3. The design allows you to solder the cable onto several RCAs.
4. The design can be used for a long period of time.
5. In this way, complex microcircuits can be easily made from polypropylene.

To remove the microcircuit, you need flux and a hair dryer with a temperature of 360 degrees.

However this system has some disadvantages, among which the following are significant:

1. High price.
2. Difficulty at work. IN in this case you must have work experience.
3. High energy consumption.

The purchase of a soldering station should also be considered if you plan to solder devices from a mobile phone.

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How to choose the right solder?

Before soldering any workpiece, you will need to choose the right solder. Only a few solders can be used to work with electrical appliances.

To solder contacts on a computer board or speaker, you should use rosin. This substance is used for soldering thin connections, copper wires, small contacts, etc. If rosin is used in electronics, then acids can remove contacts on the board and damage the main elements of the microcircuit.

For most electrical circuit boards, solder with a diameter of 0.5-1 mm is used. Thick parts can be used to connect large elements. Solder the circuit small sizes such a part will not be able to due to its large size.

During the soldering process, the solder will heat up and radiate various connections. Such gases are harmful to human health.

Therefore, you need to work in a ventilated area.

You should also be wary of exposure to hot solder; it is important to use protective equipment: masks, gloves and respirators.

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How to solder correctly with a soldering iron: sequence of actions

Items that will be needed:

• soldering iron;
• sponge;
• water;
• soap solution;
• thick cardboard or paper;
• napkin;
• insulating tape;
• wire.

It is very difficult for a beginner, but it is possible to gain fundamental knowledge. The sequence of actions in this case will be as follows:

1. First of all, the tip is tinning. You should always clean the tip of the tool you are using. Tinning is the process of coating the working element of a soldering iron with a thin layer. This process can help in thermal exchange between the material being processed and the solder.
2. After this, heating is carried out. At this stage, you should warm up the tool, and then check the uniformity of heating of the solder. If this is not done, the tool may become corroded.
3. Next, the workplace is prepared. The sponge is moistened with water and placed next to the soldering iron. If the solder spreads, you should place cardboard or thick paper.
4. Lubrication is performed. The tip must be thoroughly coated with solder. Next, the coating is checked. If there is excess solder, it will need to be removed with cardboard.
5. The upper part is covered with solder, the safety of the base is checked. The tip of the tool used is wiped with a rag to remove any remaining flux. Next, you need to prepare a sponge with a special solution. All actions should be performed quickly until the solder dries.

Step-by-step development of soldering skills

At first glance, those who have recently begun their acquaintance with electronics face simple task– learn to solder correctly.

It would seem that everything is simple - take a soldering iron, solder, rosin, and you can start assembling some interesting device. But to collect electronic homemade product, you need to have high-quality and reliable soldering skills.

Performance of any electronic device primarily depends on the reliability of electrical connections, including soldered ones. High-quality soldering skills come with experience. Therefore training is necessary . Where to start?

To learn how to solder, you first need to familiarize yourself with the theory. This will take a little time now and save it in the future. Here's what you need to know to start mastering soldering skills.

Minimum kit for soldering: soldering iron, solder, rosin, soldering iron stand.

Solders. Properties and characteristics of tin-lead solders.

Recently, lead-free solder (Lead free) has appeared on the shelves of radio stores. It is actively used in the assembly of household radio equipment. Lead-free solder differs in its properties from the widely used tin-lead solder. Read about lead-free solders.

Also during the soldering and assembly process you will need an installation tool.

After easy reading of the theory, you can safely start soldering. To practice your skills, you can solder a cube. At first it may seem that this is a simple matter, but in fact it is not.

Cube soldered from copper wire

We take copper wire with a cross-section of about 1 millimeter. If the wire is varnished, then you must first remove the insulation. It is better to do this with a pocket knife and fine sandpaper. The surface of the wire must be thoroughly cleaned so that the remaining varnish coating does not interfere with the tinning of the conductor. Even small areas of varnish insulation accidentally left after stripping will prevent further tinning. Next we tin the copper wire. You can read about tinning wires.

In the tinning process, you can use liquid flux, for example, LTI-120. Sold in tubes at radio stores. It can be equipped with a brush or a dispenser (like a pipette for applying flux in a drop).

LTI - 120

Liquid flux dries quickly. Therefore, some people dry it slightly to give it a thicker consistency.

To facilitate the process of soldering two conductors at the required angle, you can use a “third hand”. The third hand is a very useful device. It will help protect your fingers from accidental burns that can be caused by holding parts or conductors with your fingers.

If you can’t buy such a device, then something similar can be assembled using alligator clips and a few metal parts.

Soldering radio components.

You can practice soldering radio components at printed circuit boards ah from faulty equipment. An old unnecessary TV, for example, type 3USTST, is suitable for these purposes. A huge number of such televisions were stamped in Soviet time. On the printed circuit boards of such TVs, all radio components are mounted using the through-hole mounting method - THT (from English - Through Hole Technology).

The vast majority of modern radio equipment uses SMT or mixed mounting (SMT + THT). Dismantling radio elements from printed circuit boards assembled using the SMT method is complicated by the fact that SMD elements (capacitors, diodes, resistors) are very small in size and special equipment is required to solder them. That's why practice soldering all kinds of radio components With printed circuit boards, it is easier to start with boards made using the through-hole method.

If there are no particular difficulties with soldering conventional radio components, you can begin training your skills in soldering SMD elements. In modern electronics, mounting radio components on the surface is very popular and this trend will continue - the parts will become smaller and smaller.

To solder SMD components, it is advisable to acquire a hot air soldering station.

Read more about hot air soldering station.

It is very difficult to desolder SMD elements from a board with a regular soldering iron, and multi-pin parts like microcircuits are generally unrealistic, so a hot air soldering station is simply necessary. It simplifies the process of mounting and disassembling multi-terminal planar microcircuits, miniature SMD transistors, resistors and capacitors. If you are involved in radio electronics and plan to master electronics repair and, for example, cell phone repair, then do not doubt that a hot-air soldering station will be useful to you.

Also, do not forget about safety rules. It is advisable that the room in which soldering occurs is ventilated. Try not to inhale rosin fumes.

Do not overheat the PCB. This will prevent it from swelling and delamination. It is also worth protecting your eyes and face. It is not uncommon that the leads of parts spring back under the influence of elastic forces, spraying droplets of liquid solder in all directions. A similar situation occurs when a printed circuit board overheats, when the copper traces peel off and liquid solder splashes around the sides. Try to avoid such cases!

An ounce of practice is better than tons of instructions!

First, let's look at the soldering process. Soldering is the process of forming mechanical and electrical contact between metal surfaces, capable of withstanding significant mechanical loads. Soldering is formed when high temperatures(from 180 to 250 ° C) soldered surfaces and molten tin. For high-quality soldering, it is not enough to heat one surface with tin and lean another against it: required condition formation of reliable contact - equal temperatures of the surfaces being soldered. Naturally, this can only be achieved with the help of the right tool.

Important note: low temperature of the soldering iron tip will soften the solder but not melt it. The result is cold soldering (you can tell by the grainy structure of the contact). Overheated tip - excessive evaporation of solder. Both defects lead to scattering/delamination of the contact after some time of operation.

We must not forget about the temperature limits of electronic components: soldering at a temperature of ~ 250°C should not take more than 10 seconds. This is a time-tested law: integral components can easily be burned out.

To summarize the above, we will determine the requirements for soldering equipment for a radio amateur:
1. It is advisable to purchase not just a soldering iron, but a soldering station. Would you say more expensive? Yes, but not by much. Prices for good soldering stations start from 800 rubles. More expensive than a soldering iron on the radio market? But what are the advantages: adjustable heating range (the likelihood of burning out components is reduced); maintaining a constant temperature of the tip (the tip does not burn out - the cost of consumables is reduced); important feature all soldering stations - the presence of a stand for a soldering iron (a necessary thing) and a bath for a cleaning sponge - if you don’t want to buy a station, you will look for these things separately.
2. The power of the soldering iron is a thing that largely determines the quality of soldering. When soldering printed circuit boards, a soldering iron with a power of 25-40 W is sufficient. Personally, I have been using stations with a power of 40 W for 10 years and have no problems. Of course, when soldering wires with a cross-section of 10 mm, even 100 W will not be enough for you - but here we are talking about soldering boards.
3. Supply voltage - in Russia the standard voltage is 220 ±10% V, 50 Hz. If you want to solder while connecting to the power supply, buy a soldering iron/station with such power. For soldering in a car or in places where it is difficult to find an outlet, you can find a soldering iron with a power supply of 12/18/24 V or gas soldering irons.
4. An important parameter when soldering boards is the shape of the tip. Nowadays a wide range of tips is offered for soldering irons/stations - spatula, cone, needle, etc. Which one to choose is up to you: it’s convenient for everyone to solder with what they’re used to. I use spatulas of different sizes.
5. An important parameter is the durability of the tip. You can find heat-resistant tips that are not afraid of prolonged overheating. Convenient, but expensive.
6. It is impossible not to mention antistatic soldering stations. If you are willing to pay more than $100 for a soldering station, you will receive antistatic protection (useful when soldering field elements and other capricious items). There is no such money - don’t be upset - you can modify the station / soldering iron yourself: grounding the tip helps in most cases. This is, of course, not the antistatic agent that is found in fancy stations, but it helps no worse.

Well, have you got yourself some soldering equipment? Next step - Consumables. You will need flux - to remove oxides from contact pads of boards and component leads, and solder.

Flux selection- a separate question. Your grandfather soldered with rosin - smile indulgently - there was no other before. Why rosin is bad - rosin, alcohol rosin flux belong to the category of active fluxes. The main disadvantage is that at high temperatures not only the metal oxide is removed - the metal itself is also removed. Look at the tip of your grandfather's soldering iron - everything is full of potholes, black and jagged. This is the effect of rosin. Another main disadvantage is cleaning the board after soldering with rosin a big problem. The only way to wash off the residue is with alcohol or solvents (and even then, sometimes it’s easier to pick it out with something sharp). Flux residues on the board are not only unsightly from an aesthetic point of view, but also harmful. On boards with small gaps between conductors, the growth of dendrites (in other words, short circuits) caused by galvanic processes on a contaminated surface is possible.

What is the way out? modern market materials, you can find a wide range of fluxes that are washed off with ordinary water, do not destroy the soldering iron tip and provide high quality rations. Such fluxes are usually sold in syringes, which is very convenient for use.

Solder selection. Did your grandfather recommend you a 10mm tin rod? Smile again. Nowadays, solder wire with a cross-section of 1 to 5 mm is used for soldering. The most common are 1.5-2 mm multi-channel solders. Multi-channel means that inside the tin wire there are several channels of flux, which ensures the formation of an even, shiny and reliable solder. Such solder is sold in coils - on, in flasks - in which it is rolled into a spiral, and in reels (the amount of solder in them is such that it will last for more than one year).

Sting activator. Tip Activator or TipCleaner is sold in very small jars. It is necessary to increase the service life of the soldering iron tip. Before and after each soldering (meaning at the beginning and at the end of work), lower the tip into this jar. It forms protective covering, preventing the formation of soot.

Well, are you ready to solder? The last thing you need is hand tool: knife, wire cutters, pliers. If you need anything else during the work, you will understand for yourself.

Before soldering the board, you need to prepare workplace: take care of a container with low sides and enough large area for debris - bitten off leads and removed braiding. A plastic disposable plate works very well (do not touch it with the tip of a heated soldering iron:). Take care of the lighting too - the light should fall on the board so that the hand with the soldering iron does not cover it.

Now you are a real SOLDERER (though not yet an experienced one, but you are catching up).

Before you start soldering, understand the board. If you did it yourself, most likely it is without solder coatings: bare copper. Before soldering, all contact pads will have to be tinned: cover them with flux and apply tin with a soldering iron so as not to cover the holes in the board. With the right temperature and good flux, the tin from the soldering iron tip itself will “flow” around the entire contact pad as soon as you touch it. You shouldn’t put huge drops of tin on the soldering iron tip: touch the tip to the rod and in a second the required amount will be on the tip.

A tin-plated board - industrially manufactured - eliminates this work, but also costs accordingly.

Is the board ready? If necessary, remove any remaining flux and you can begin soldering.

One of the main mistakes novice radio amateurs make is soldering components and then cutting off the extra length of the legs. At the same time, it is difficult to achieve high-quality contact - increased heat dissipation and complicated access of the tip to the soldering site only worsen the formation of a reliable connection. Shape component leads and trim them before soldering.

As I already noted - when the right technology the tin will “flow around” the contact on its own. Pay attention to the condition of the component leads: gray matte leads are oxidized. You'll have to play around with flux. Be careful - you can burn the component. If you want to avoid trouble, buy components in electronic stores - they are stored properly there.

Knowing how to use a soldering iron is a very useful skill for anyone. It’s the right way to use it, and not just poke it into the solder. To be able to solder well is a real art, which is not acquired immediately, but as a result of practice. A little terminology: solder is a low-melting metal alloy that is used to solder wires and leads of parts. More often, tin-lead solders are used, which are an alloy of tin and lead. In terms of soldering strength, these solders are not inferior to pure tin. Such solders melt at a temperature of 180 - 200 ° C. They are abbreviated as POS (tin-lead solder), followed by a two-digit number indicating the tin content as a percentage, for example: POS-40, POS-60. It’s even better to take the so-called low-melting Wood’s alloy with a melting point of about 70 °C.

Flux is used to ensure that areas of parts or conductors prepared for soldering do not oxidize during soldering. To solder circuit boards, you must use fluxes that do not contain acid. The simplest and most common flux is rosin. It is better to buy natural pine rosin. Much best result You can get it if you stock up on liquid flux. To prepare it, grind rosin into powder and add it to ethyl or boric alcohol. This rosin is applied to the soldered areas with a brush. Having bought a new soldering iron, the tip must be cleaned and tinned - covered with a thin layer of solder. When you first turn on a new soldering iron to the network, the connecting components of the insulation usually burn out - an unpleasant smelling smoke comes out of the soldering iron, so it is better to turn on the soldering iron for the first time in the open air. Now clean the soldering iron tip with a file, then heat the soldering iron again. Dip the tip into the rosin and then touch it to a piece of solder. In a layer of molten solder, move the tip along a wooden stand so that its entire surface is covered with a layer of solder.

When soldering small radio components, it is convenient to have a very thin soldering iron tip, literally a couple of millimeters in diameter. It is not convenient to solder boards with an overheated soldering iron. Moreover, there is a danger of overheating the soldered radio components. It is advisable to equip a soldering iron