Learn to solder- The basics of soldering for dummies.

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(C) Igor Majorov, 1996 (R) Sergey Romanov and Fedy Savin, 1997 ────────────────────────── Let's take a simple soldering iron in hand. To get started, let's prepare it for work: The tip (the very tip of the soldering iron) should be silver. If this is not the case, then we take a file or file and carefully clean it. Then, we take a file and give the tip the shape of either a "blade" if you need to solder two wires, or a "needle" or "cone" for working with the board, for example. (see fig.) Now we turn on the soldering iron in the network, wait until it heats up, and successively touch the sting (dip the sting) first to the rosin, and then to the tin, and so that the tin evenly covers it. After that, wipe the sting on a piece of cloth. Everything. The soldering iron is now ready to go.The next step is proper soldering.Usually, for beginners, after the first soldering, they get something sealed with a PIECE of tin. Do not be afraid if you get the same result. Skill comes with experience ... To begin with, let's try to solder together two "single-core" wiring, of which in bulk in any house. For good soldering, we first enroll the wires about 5 mm in length. For this, a sharply sharpened cutting tool such as a surgical scalpel, knife, nippers, or, at worst, sharp scissors is most often used ... Carefully, trying not to cut your fingers, remove the insulation from the wiring. It's okay if the first time, instead of stripping the insulation, you bite the wire whole. A few tries, and you will definitely succeed. After removing the insulation, scrape the exposed part, for example with a knife. The part should shine more. So, the wire is stripped. Now it must be "tricked" or "tinned" - and so, and so they say. We take the stripped wire and press it into the rosin for a short time with a hot soldering iron, and then take it out. After that, having melted a small piece of tin with a soldering iron, again touch the end of the wire, which has been degreased with rosin, and slightly rotate it around its axis so that the tin evenly covers the stripped area. We carry out the same operation with the second wire. Then, putting the "tinned" wires on top of each other, we touch them with a hot soldering iron, having previously dipped it in canin. Everything. Now we take away the soldering iron and let the wires cool down, in no case blowing on them - this deteriorates the quality of the soldering. A few words about how you need to solder several wires with yourself:-Correct wire soldering. -Incorrect wire soldering.Now let's talk about how to handle the printed circuit board and its elements. The printed circuit board is a sheet of foil-coated getinax or textolite, on which the conductive tracks are etched. There are holes (holes) on the board, where the circuit elements will then be soldered, well, that is, all sorts of details. Usually these holes are already tinned, so there are no special problems. But if you come across a "left" board, then before installation, printed conductors and contact pads must be prepared for soldering - cleaned of oxide film and impurities. If a lot of time has passed since the production of the board and the metal coating has darkened (oxidized), then first you need to clean it to a shine with a fine-grained skin, and then rinse thoroughly with alcohol (optional). After degreasing, a thin layer of rosin flux is applied to all contact pads of the board with a brush. (Composition,%: Rosin - 15-18, the rest is alcohol; Rosin - 6, Glycerin - 14, ethyl alcohol - everything else). Well, if you did not have anything from the composition of the flux, you do not need to get upset, you can just take a little tin with the tip of the soldering iron, then we press it a little into the rosin and quickly (until the rosin evaporates) we touch the place that needs to be tinned with a sting, and a little after waiting, we remove it. That place is getting dirty. If your hole is filled with tin, it means you took too much of me on the sting. The latter method requires a good amount of training. Radioelements and microcircuits also need to be prepared for installation and soldering. To do this, their conclusions (legs) are shaped (they are given the desired shape), cut to the required length, if required, cleaned and tinned. Forming can be done with tweezers, mini pliers or other similar tools / tools. Since the adhesion of the foil to the board is not high and decreases with heating, try to keep the soldering iron from heating the board for more than 5 seconds. For soldering boards, a low melting point solder should be used: POSK 50, POS 61, etc. Soldering iron power - no more than 35-40 W. The soldering iron should have a needle-shaped tip (although this is at your discretion), sharpened and tinned. Soldering of all elements of the circuit is carried out as well as soldering of 2 irradiated wires, ie. insert the legs of the parts into the required holes and heat them one by one.

My relationship with radio and microelectronics can be described by a wonderful anecdote about Leo Tolstoy, who loved to play the balalaika, but could not. Sometimes he writes the next chapter of War and Peace, and he thinks "trendy-brandy trendy-brandy ...". After courses in electrical engineering and microelectronics at my beloved Moscow Aviation Institute, plus the endless explanations of my brother, which I forget almost immediately, in principle, I manage to assemble simple circuits and even come up with my own, good now, if I don't feel like messing around with analog signals, amplifications, pickups, etc. you can find a ready-made micro-assembly and stay in the more or less understandable world of digital microelectronics.

To the point. Today we will talk about soldering. I know that many beginners who want to play with microcontrollers are intimidated by this. But, firstly, you can use
So, we are almost there. I write everything in such detail, because, honestly, for me it was a breakthrough. As I accidentally discovered, all that is needed for soldering simple components is a soldering iron, the most common one with a sting in the form of an awl:

And solder with flux inside:

It's all about the process. You need to do this:

• The part is inserted into the board and must be secured (you will not have a second hand to hold).
• A soldering iron is taken in one hand, and a solder wire in the other (it is convenient if it is in a special dispenser, as in the picture).
• Take solder on a soldering iron NO NEED.
• Touch the tip of the soldering iron to the soldering point and heat it. Usually, it is 3-4 seconds.
• Then, without removing the soldering iron, with your other hand touch the tip of the solder wire with flux to the soldering point. In reality, all three parts touch at this place at once: the soldering element and its hole on the board, the soldering iron and the solder. A second later, "pshshshshsh" occurs, the tip of the solder wire melts (and a little flux flows out of it) and the required amount goes to the place of soldering. After a second, you can remove the soldering iron and blow.

The key point here, as you already understood, is the supply of solder and flux directly to the soldering point. And the flux "built-in" in the solder gives it the required minimum amount, reducing clogging of the board to a minimum.

It is clear that the waiting time in each phase requires at least minimal practice, but no more. I am sure that any beginner using this technique will solder Maximite himself in an hour.

Let me remind you the main signs of good soldering:

• A lot of solder does not mean quality contact. A drop of solder at the point of contact should cover it on all sides, without any potholes, but not be an excessively huge bulb.
• The color of the solder should be closer to shiny, not matte.
• If the board is double-sided and the holes are not plated, it is necessary to solder using the specified technology on both sides.

It is worth noting that all of the above refers to the soldering of elements that are inserted into the holes on the board. For soldering planar parts, the process is a little more complicated, but real. Planar elements occupy less space, but require a more accurate location of the "patches" for them.

Planar elements (of course, not the smallest ones) are even easier to solder in some way, although for homemade devices you will already have to etch the board, since there will be no special convenience from using planar elements on the breadboard.

So, a small, almost theoretical bonus about soldering planar elements. These can be microcircuits, transistors, resistors, capacitors, etc. I repeat, at home there are objective restrictions on the size of elements that can be soldered with an ordinary soldering iron. Below I will give a list of what I personally soldered with an ordinary 220V soldering iron-awl.

For soldering a planar element, it will no longer be possible to use solder on the go, since it can "come off" too much, "pouring" several legs at once. Therefore, it is necessary to preliminarily tin the spots where the component is planned to be installed. Here, alas, it is no longer possible to do without liquid flux (at least I did not succeed).

You drip a little liquid flux onto a patch (or patch), take quite a bit of solder onto the soldering iron (you can do it without flux). For planar solder elements, very little is generally needed. Then lightly touch the tip of the soldering iron to each patch. Some solder should come off it. More than necessary, each patch will not "take".

Take the element with tweezers. Firstly, it is more convenient, and secondly, the tweezers will remove heat, which is very important for planar elements. Attach the element to the soldering point, holding it with tweezers. If this is a microcircuit, then you need to hold it by the leg that you are soldering. For microcircuits, the heat sink is especially important, so two tweezers can be used. You hold the part with one, and attach the other to the soldered leg (there are tweezers with a clip that you do not need to hold with your hands). With the other hand, you again apply a drop of liquid flux to the soldering point (it may get a little on the microcircuit), with the same hand you take the soldering iron and touch the soldering point for a second. Since the solder and flux are already there, the leg to be soldered will be "immersed" in the solder applied at the tinning stage. Then the procedure is repeated for all legs. If necessary, you can drip in liquid flux.

When you buy a liquid gumboil, buy a liquid for cleaning the boards. Alas, with liquid flux, it is better to wash the board after soldering.

I must say right away that I am never a professional, and not even an advanced amateur in soldering. I did all this with an ordinary soldering iron. Pros have their own methods and equipment.

Of course, soldering a planar element requires a lot more skill. But it's still quite possible at home. And if you do not solder the microcircuits, but only the simplest elements, then everything is still simplified. Microcircuits can be bought already soldered into pads or in the form of ready-made assemblies.

Here are pictures of what I personally successfully soldered after a little workout.

This is the simplest type of enclosure. These can be put in pads, which are the same in terms of soldering complexity. These are simply soldered according to the first instruction.

The next two are harder. Here it is already necessary to solder according to the second instruction with a neat heat sink and liquid flux.

Elementary planar components, such as the resistors below, are quite easy to solder:

But there is, of course, a limit. This good is already beyond my abilities.

As a curtain, a couple of cheap but very useful things to buy in addition to a soldering iron, solder, tweezers and wire cutters:

Good luck in soldering! The smell of rosin is cool!

The ability to solder in modern life saturated with electrical appliances and electronics, as necessary as the ability to use a screwdriver and plunger. There are many methods of soldering metals, but first of all you need to know how to solder with a soldering iron, although in domestic conditions other methods are feasible and may also be needed. To help those wishing to master the technology of manual adhesive work, this article is intended.

Note: soldering of propylene and other plastics here we do not touch. This, in fact, is not soldering - in the technical process there are no mandatory components for adhesive work, solder and flux. Technologically, plastics soldering is closer to low-temperature contact welding... The same goes for cold soldering- joining parts with conductive glue.

Soldering metals with solder is quite difficult physicochemical process, but in work it comes down to fairly simple techniques and operations. In order to solder correctly, without wandering in the wilds of theory, the rules for the production of adhesive work must be followed exactly . This especially concerns the choice of the soldering method, solder and flux, depending on the type of parts to be joined and the requirements for the soldered joint. The main part of the presented material is devoted to the description of these and other details, without which a strong seal will not work.

Note: If you want to quickly solder something, you can watch an in-depth video tutorial on the basics of soldering for beginners below. But keep in mind that it will not replace the rest of the text. In adhesive work, the rule “do it this way, it will turn out so” does not always apply. And in a well-established production, it happens that you have to rack your brains - but what if it turns out wrong? Or, what needs to be done to make it all the same, if there is not something that is supposed to do so.

Video: how to learn to solder - a lesson for beginners

What is soldering?

Do-it-yourself soldering at home comes down to the following technological operations:

• The brazed surfaces are cleaned of dirt, corrosive crusts, etc.
• Cleaned to a shine, i.e. to the absence of visible traces of oxides;
• They are covered with a flux - a substance that removes oxide residues and does not allow oxidation of surfaces in the further process. For fluxing for tinning, it is preferable to use not liquid or solid fluxes, but flux-pastes;
• Then the surfaces are tinned - molten solder is applied to them (an alloy specially designed for soldering), while it spreads out with a thin film and chemically combines with the base metal;
• The parts are pre-connected mechanically: by twisting, squeezing with tweezers, pliers, in a vice, clamp, etc.
• Another flux is applied to prevent the oxidation of the solder under heating;
• Solder is applied with warming up (possibly already different) until a weld of a given quality is obtained;
• If soldering was carried out with a soldering iron with a tinned tip (see below), at the end it is cleaned and covered with an inactive flux. In order for the soldering to be of high quality, a regular soldering iron must be stored with a fluxed tip!

A necessary retreat

Note: in the northern dialects of Russian there are also ludas - underwater stone ridges - and even the sig-ludoga fish, which is found there. But in the canonical Russian, ludas are extremely rare, so they can be ignored.

Stripping

Stripping after cleaning is the first tricky soldering operation. The use of abrasives for it is unacceptable! Their smallest particles, embedded in the metal, cannot be completely removed. Subsequently, they become hotbeds of processes that destroy the seam.

The surfaces for soldering are cleaned with a file, a file, a scraper tool ( different types scrapers) or just with a knife. But best of all, especially if current-carrying wires are being prepared for soldering, immediately cover them with activated flux (see below), and after soldering, carefully remove its remnants. It is convenient to do this with a toothbrush moistened with alcohol.

How and how to tin / solder?

For the following operations, you will need a special electric heating tool: a soldering iron, a case or soldering torch... Soldering at home is most often done with an electric soldering iron with a tinned copper tip. Its device is shown in pos. 1 fig. "For complete happiness" of an amateur solder, rod soldering irons for 16-20 W are needed for microcircuits and printed circuit boards, pos. 2a, 40-50 W (pos.2b), for electric wires and surface-mounted component of radio electronics, and 80-150 W (pos. 2c), for the assembly of small metal structures by soldering.

The device and varieties of electric soldering irons with a tinned copper tip

If you do not intend to work with microchips (phones, tablets, computers) and soldering steel with a thickness of more than 0.5-0.6 mm, you can get by with a set of soldering irons for 25 W (pos. 3a) and 60-65 W, pos. 3 b. Suddenly there will be a need to solder metal profiles with a wall thickness of up to 3-4 mm and / or a thick steel sheet, you will need a 300-400 W radiator-type "ax" soldering iron, pos. 4.

Soldering iron tips low power(pos. 2a, 2b, 3a, 3b) are not initially forged and therefore rather quickly oxidize (burn). To increase their durability, and at the same time to shape them as needed, the rod removed from the soldering iron is hammered with a metal hammer on the anvil of a table vise. There is no need to “scratch” it with a file after that, and it is not necessary, so as not to erase the outer compacted layer of copper. After forging, the tip is immediately coated with an activated flux.

Now you need solid rosin and soft, sufficiently refractory solder (see below): POS-10, POS-30 or POS-40. The soldering iron rod is inserted into place, fixed if there is a retaining screw, and the soldering iron is connected to the network. As the flux boils away during heating, the sting is immersed in rosin so that it does not become bare. When the rosin around the tip begins to bubble, rub it with a solder stick until an even, dense half is obtained on the entire surface of the tip. The thread solder on the spool is not very good in this case, it is for soldering small parts.

While we were preparing the soldering iron, the flux on the soldering surfaces did its job: they are clean under its layer, you can tin it. Here the critical point will be the thickness of the parts:

• Less than 1/8 of the diameter of a soldering iron rod - will warm through to the melting point of the solder in less than 7 seconds. The flux will not have time to boil away.
• More than 1/6 of the same value - they will warm up in more than 10 s, the flux will boil away, the parts will become bare and oxidized.
• 1 / 8-1 / 6 of the diameter of the rod - you need, most often based on your own experience, to tin with low-melting solder under a high-boiling flux. Or use a more powerful soldering iron.

In the first case, a drop of solder is collected on the tip, transferred to the surface to be soldered, and if:

• The wire is thin - easily, without pressure, move along the bare end with a sting from one and then from the opposite side, until the solder spreads. The wire is held with the tip down. A drop of excess solder that has dripped there is removed with a soldering iron.
• The wire is thick - the sting is moved in a spiral back and forth.
• Flat thin long piece - the solder is applied to the end and the tip is moved along. When the non-tinned edges of the part appear behind the sting, they apply more flux to the underexposed area, collect another drop of solder and continue tinning.
• Longer wider part - same as before. case, but the sting is led by a snake.
• Wide detail - the sting is moved in a spiral from the center to the edges.

For tinning thick parts, take thread solder with flux, the so-called. harpius: this is a thin flexible tube made of solder foil, in the lumen of which is powdered rosin. Tinning begins at the edge of long or in the middle of wide pieces. The end of the harpius is applied to the place where the tinning begins, heated with a soldering iron until it spreads. Sting movements are the same as before. cases. Solder served under the sting as it is spent. Give on the sting - it will stick to it until a large drop forms, which will drain where it is not necessary.

Features of wire soldering

In the preliminary connection of soldered parts, the most problems arise with wires: for this you have to touch them with your hands, which makes the metal surface dirty, and the soldering of the wires, more often than other soldered joints, have to withstand mechanical loads.

Wire strands

Before soldering the wires, they must be properly twisted. The main types of wire twists for soldering are shown in Fig. Each of them has its own purpose:

• Bandage twists connect rigid (thick single-core) current-carrying wires, i.e. through which electric power is transmitted. Especially - external wires. The shroud connection provides sufficient electrical contact even if the oxidized junction is missing or overheated.
• Grooved twists are made on wires in low-melting insulation ( plain PVC, polyethylene), when complete spreading of the solder with minimal heating is required. The flute twists are heated only along the groove.
• Simple twists can be used to connect both single-core and multi-core wires that have just been stripped of insulation (shiny).
• Simple sequential twisting, the so-called. direct British, or simply British, is applicable for connecting live wires of flexible cables with a cross section of up to 1.4 sq. mm, not experiencing regular heavy mechanical stress, for example. electrical extension cords or makeshift.

Electrical wires undergoing regular and / or constant mechanical stress must be stranded. Twist them, as shown in the figure below: the ends are marked out, the "brooms" are pushed into each other and twisted in the British style. Soldered with high-strength low-melting solder, for example. POSK-50 (see below) with an activated flux that does not require removal of residues, also see below.

Parallel (dead-end) twisting of wires with a cross section of over 0.7 sq. mm, it is desirable to solder by immersion in molten solder, see below. Otherwise, you will have to warm up either for a long time, or too powerful soldering iron, which is why the insulation creeps, and the flux boils away prematurely.

Note: single-core tinned wires - terminals of radio electronics parts - it is permissible to solder end-to-end or with a crochet hook, see fig. on right.

What is soldered but not soldered

Flexible coaxial cables and cables for computer networks of the twisted pair type are not intended for soldering. An experienced cable technician who has a complete understanding of the electrodynamics of signal transmission lines, in exceptional cases, can make a sleeve on them. But when performed by an amateur, even if he is an otherwise qualified electronics engineer and installer, the bandwidth and noise immunity of the line will fall below the permissible level, up to a complete loss.

How to clean and preserve a sting

The soldering iron tip is cleaned of solder residues by rubbing against a soft porous or fibrous lining. Foam rubber is most often used, but this is not the best option: it burns and sticks to the sting. The best material for cleaning it is natural felt or basalt cardboard. But even better - a 2-step cleaning, first with a sponge made of metal tape, and then with felt. After cleaning, the soldering iron is turned off, an even hot tip is injected into the solid rosin and wait until it stops bubbling. Then remove the sting and hold the end down to drain the excess rosin. When it cools completely, the soldering iron can be sent for storage.

Solders and fluxes

Now the time has come to choose the correct working solder and flux for it, because soldering, unlike half a day, must not only adhere firmly to the base metal, but also be strong itself. A summary of the information on solders and fluxes of widespread use from the old handbook is given in Fig. With regard to the present time, there is not much to add to it.

Characteristics of solders and fluxes for general use

Solders from POS-90 to Avia-2 are soft for low-temperature soldering. Only electrical contact is guaranteed. POS-30 and POS-40 solder copper, brass, bronze with inactive fluxes, and the same with steel and steel and steel with active ones. POSSr-15 can be soldered galvanized with inactive fluxes; other solders will corrode the zinc to steel and the soldering will soon fall off.

34A, MF-1 and PSr-25 solid solders for high-temperature brazing. Solder 34A can be used to solder aluminum in a flame (see below, about soldering aluminum) with special fluxes, see ibid. Solder MF1 solder copper to steel with activated flux. "Low strength requirements" in this case means that the strength of the joint is closer to that of copper than steel. PSr-25 when soldering with a dry soldering iron (see below) is suitable for soldering jewelry, tiffany stained-glass windows, etc.

Soldering fluxes are divided into neutral (inactive, acid-free), chemically not interacting with the base metal or interacting to an insignificant extent, activated, chemically acting on the base metal when heated, and active (acidic), acting on it and cold. With regard to fluxes, our century has brought the most innovations; most of them are good, but let's start with the unpleasant ones.

First, there is no longer commercially pure acetone for washing rations, due to the fact that it is used in the clandestine production of drugs and itself has a narcotic effect. Substitutes for technical acetone - solvents 646 and 647.

The second is that zinc chloride in activated flux pastes is often replaced with teraborate sodium - brown. Hydrochloric acid- highly toxic chemically aggressive volatile substance; zinc chloride is also toxic, and when heated, it sublimes, i.e. evaporates without melting. Borax is safe, but when heated, it emits a large amount of crystallization water, which slightly impairs the quality of the soldering.

Note: borax itself is a soldering flux for dipping into molten solder, see below.

The good news is that now there is a wide range of fluxes on sale for all cases of soldering life. For ordinary adhesive work, you will need (see fig.) Inexpensive SCF (alcohol rosin, former CE, second in the list of acid-free fluxes in Table I.10 in the figure above) and soldering (etched) acid, this is the first acid flux in the list. SCF is suitable for brazing copper and its alloys, and soldering acid is suitable for steel.

Soldering from SCF must be flushed: rosin contains succinic acid, destroying metal upon prolonged contact. In addition, an accidentally spilled SCF instantly spreads over a large area and turns into a very long-drying extremely sticky muck, stains from which cannot be removed from clothes, furniture, or floors with walls. In general, GFR is a good flux for soldering, but not for muddleheads.

A full-fledged substitute for GFR, but not so disgusting if handled carelessly, is the TAGS flux. Steel parts are more massive than permissible for soldering with soldering acid, and more firmly, they are soldered with F38 flux. The universal flux can be used to solder almost any metal in any combination, incl. aluminum, but the strength of the junction with it is not standardized. We'll come back to soldering aluminum later.

Note: radio amateurs, keep in mind - now there are fluxes on sale for soldering enameled wires without stripping!

Other types of soldering

Lovers of tinkering also often solder with a dry soldering iron with a bronze bare tip, the so-called. soldering pencil, pos. 1 in fig. It is good where the spreading of solder outside the soldering zone is unacceptable: in jewelry, stained-glass windows, soldered objects applied arts... Sometimes surface-mounted microchips are also dry-soldered with a pin spacing of 1.25 or 0.625 mm, but this is also a risky business for experienced specialists: poor thermal contact requires excessive soldering iron power and prolonged heating, and it is impossible to ensure the stability of heating during manual soldering. For dry soldering, use harpius from POSK-40, 45 or 50 and flux-pastes that do not require removal of residues.

Other types of soldering that can be done at home

Dead-end twists of thick wires (see above) are soldered by immersion in a case - a bath with molten solder. Once upon a time the futorka was warmed blowtorch(pos. 2a), but now this is primitive savagery: an electrofluor or a soldering bath (pos. 2) is cheaper, safer and gives the best soldering quality. The twist is introduced into the case through a layer of boiling flux fed to the solder after it is melted and heated to working temperature... The simplest flux in this case is rosin powder, but it soon boils away and burns even faster. It is better to flux the futork with brown, and if the soldering bath is used for galvanizing small parts, then this is the only possible variant... In this case, the maximum temperature of the footboard should be at least 500 degrees Celsius, because zinc melts at 440.

Finally, massive copper in products, for example. pipes are brazed by high-temperature flame brazing. It always contains unburned particles that greedily absorb oxygen, so the flame has, as chemists say, reducing properties: it removes residual oxide and prevents new ones from forming. On pos. 3 you can see how the flame of a special soldering torch literally blows out everything unnecessary from the soldering zone.

Manual high-temperature flame brazing

High-temperature brazing is carried out, see fig. on the right, evenly rubbing with pressure the soldering zone 1 with a stick of hard solder 2. The flame of the burner 3 should follow the solder so that the hot spot does not come out in the air. The soldering zone is preliminarily heated until the tarnishing colors appear. Something else can be soft-soldered to the hard-soldered surface as usual. For more on flame brazing, see below when it comes to pipes.

Curiously, some sources call the soldering torch a soldering station. Well, a rewrite is a rewrite, what can you take from it. In fact, a desktop soldering station (see next figure) is equipment for delicate soldering work: with microchips, etc., where overheating is unacceptable, spreading of solder where it is not necessary, and other flaws. The soldering station precisely maintains the set temperature in the soldering zone, and, if the station is gas-fired, it controls the gas supply there. In this case, the burner is included in its kit, but the soldering torch itself is a soldering station no more than a quarry - St. Basil's Cathedral.

Desktop soldering stations

How to solder aluminum

Soldering fluxes for aluminum

Thanks to modern fluxes, brazing aluminum is generally no more difficult than copper. F-61A flux is intended for its low-temperature soldering, see fig. Solder - any analogue of Avia's solders; there are different ones on sale. The only thing is that it is better to insert a tinned bronze rod into the soldering iron with notches on the tip, approximately like a file. Under a layer of flux, it will easily scrape off a strong oxide film, which does not allow aluminum to be soldered just like that.

Flux F-34A is intended for high-temperature brazing of aluminum with 34A solder. However, it is necessary to heat the soldering zone with a flame very carefully: the melting temperature of aluminum itself is only 660 Celsius. Therefore, it is better to use high-temperature brazing of aluminum in a flameless chamber (brazing with oven heating), but the equipment for it is expensive.

Copper plating of aluminum for soldering

There is also a "pioneer" method of brazing aluminum with preliminary copper plating. It is suitable when only electrical contact is required, and mechanical stresses in the soldering area are excluded, for example, if it is necessary to connect an aluminum casing with common bus printed circuit board. "Pioneer" brazing of aluminum is carried out on the installation shown in Fig. left. Powder copper sulfate poured with a slide into the soldering area. Toothbrush harder, wrapped in bare copper wire, dipped in distilled water and rubbed with vitriol with it. When a copper stain appears on the aluminum, it is tinned and soldered as usual.

Fine soldering

Soldering PCBs has its own characteristics. How to solder parts to printed circuit boards, in general, see a small master class in the pictures. Tinning of wires is eliminated, because the leads of the radio component and the chips are already tinned.

In an amateur environment, firstly, it makes little sense to tin all current-carrying tracks if the device operates at frequencies up to 40-50 MHz. V industrial production boards are tinned with low-temperature methods, for example. spraying or electroplating. Heating the tracks with a soldering iron along the entire length will worsen their adhesion to the base and increase the likelihood of delamination. After assembling the component, it is better to varnish the board. Copper will immediately darken from this, but this will not affect the performance of the device in any way, unless we are talking about a microwave.

Soldering electronic components to a printed circuit board

Then, look at something ugly on the left of the trail. rice. For such a marriage and in the bad memory of the Soviet MEP (Ministry of Electronic Industry), assemblers were demoted to loaders or auxiliary workers. It's not even about appearance or excessive consumption of expensive solder, and, firstly, during the cooling of these plaques, both the mounting pads and the parts overheated. And large heavy solder beads are rather inert weights for already weakened tracks. Radio amateurs are well aware of the effect: I accidentally pushed the cuttlefish board onto the floor - 1-2 or more tracks peeled off. Without waiting for the first soldering.

Incorrectly and correctly wired printed circuit boards

Solder beads on printed circuit boards should be rounded smooth with a height of no more than 0.7 of the diameter of the mounting pad, see on the right in Fig. The tips of the leads should protrude slightly from the beads. By the way, the board is completely homemade. There is a way at home to make printed wiring as accurate and precise as a factory one, and even print there the inscriptions you want. White spots - glare from varnish when photographing.

Concave and even more wrinkled nodules are also a marriage. Just a concave bead means that there is not enough solder, and wrinkled, except that air has penetrated into the solder. If the assembled device does not work and there is a suspicion of non-drip, look first of all at such places.

ICs and chips

In fact integrated circuit(IC) and the chip are the same, but for clarity, as is generally accepted in technology, microcircuits-"mikrukh" will leave ICs in DIP-packages, up to large in terms of integration, inclusive, with leads every 2.5 mm, installed in mounting holes or solder caps if the board is multilayer. Let the chips be super-large ICs - "million-plus", mounted on the surface, with a lead pitch of 1.25 mm or less, and microchips - miniature ICs in the same cases for phones, tablets, laptops. We do not touch processors and other "stones" with rigid multi-row pins: they are not soldered, but installed in special sockets, which are soldered into the board once when it is assembled at the enterprise.

Soldering iron ground

Modern CMOS (CMOS) ICs in terms of sensitivity to static electricity are the same as TTL and TTLSh, they hold a potential of 150 V for 100 ms without damage. The peak value of the operating voltage of the 220 V network is 310 V (220x1.414). Hence the conclusion: a low-voltage soldering iron is needed, for a voltage of 12-42V, connected through a step-down transformer on the iron, not through a pulse generator or capacitive ballast! Then even a direct breakdown on the sting will not spoil the expensive chips.

There are still accidental, and even more dangerous, mains voltage surges: the welding was switched on nearby, there was a mains surge, the wiring sparkled, etc. The most reliable way to protect yourself from them is not to divert the "wandering" potentials from the tip of the soldering iron, but not to let them out of there. For this, even at special enterprises of the USSR, a circuit for switching on soldering irons was used, shown in Fig.:

Low voltage electric soldering iron grounding diagram

The C1 C2 connection point and the transformer core are connected directly to the protective grounding circuit, and to the middle point of the secondary winding - the shield winding (open loop of copper foil) and the grounding conductors of the workplaces. This point is connected to the circuit with a separate wire. With sufficient power of the transformer, you can connect as many soldering irons as you like to it, without worrying about grounding each separately. In the home, points a and b are connected to the common ground terminal with separate wires.

Microcircuits, soldering

Microcircuits in DIP-cases are soldered like other electronic components. Soldering iron - up to 25 W. Solder - POS-61; flux - TAGS or alcohol rosin. It is necessary to wash off its remnants with acetone or its substitutes: alcohol takes the rosin tightly, and it is impossible to completely wash it between the legs with either a brush or a rag.

As for chips, and even more so microchips, it is strongly not recommended for specialists of any level to solder them by hand: this is a lottery with a very problematic win and a very likely loss. If it comes to such subtleties as repairing phones and tablets, you will have to fork out for a soldering station. Using it is not much more difficult than using a hand-held soldering iron, see the video below, and the prices of quite decent soldering stations are now available.

Video: lessons on soldering microcircuits

Microcircuits, soldering

"Correctly", ICs for checking during repairs are not soldered. Their diagnostics is carried out on the spot by special testers and methods, and the unusable one is removed once and for all. But amateurs cannot always afford it, therefore, just in case, below we give a video about the methods of soldering ICs in DIP cases. Chips with microchips, craftsmen also contrive to solder, for example, slipping a nichrome wire under a row of pins and warming them with dry soldering irons, but this lottery is even less winning than manual installation of large and extra-large ICs.

Video: soldering chips - 3 ways

How to solder pipes

Copper pipes are high-temperature brazed with any copper brazing alloy with an activated flux paste that does not require removal of residues. Further 3 options are possible:

• In copper (brass, bronze) couplings- soldering fittings.
• With full distribution.
• With incomplete distribution and compression.

Soldering copper pipes in fittings is more reliable than others, but requires significant additional costs for couplings. The only case when it is irreplaceable is the diverter device; then a tee fitting is used. Both surfaces to be brazed are not tinned in advance, but covered with a flux. Then the pipe is inserted into the fitting, securely fixed and the joint is soldered. Soldering is considered complete when the solder stops going into the gap between the pipe and the coupling (0.5-1 mm is needed) and protrudes from the outside with a small roller. The retainer is removed no earlier than 3-5 minutes after the solder has hardened, when the joint can already be held by hand, otherwise the solder will not gain strength and the joint will someday flow.

How pipes with full expansion are soldered is shown on the left in Fig. The pressure of the "dispensed" soldering is the same as that of the fitting, but requires additional. special tools for unfolding the socket and increased consumption of solder. The fixing of the pipe to be soldered is not necessary; it can be pushed into the socket with a twist until it jams tightly, therefore, soldering with a full distribution is often done in places inconvenient for installing the retainer.

Brazing copper pipes

In home wiring from thin-walled pipes of small diameter, where the pressure is already small, and its losses are insignificant, it may be advisable to solder with incomplete distribution of one pipe and narrowing of the other, pos. I on the right in Fig. To prepare pipes, a round stick made of hard wood with a tapered tip of 10-12 degrees on one side and a truncated-conical hole at 15-20 degrees on the other is sufficient, pos II. The pipe ends are machined until they fit into each other for approx. by 10-12 mm. The surfaces are tinned in advance, applied to the tinned ones with more flux and connected before jamming. Then it is heated until the solder melts and the tapered pipe is supported until it is jammed. Solder consumption is minimal.

The most important condition for the reliability of such a joint is that the narrowing should be oriented along the water flow, pos. III. Bernoulli's school law is a generalization for an ideal fluid in a wide pipe, and for a real fluid in a narrow pipe, due to its (fluid) viscosity, the maximum pressure jump shifts opposite to the current, pos. IV. A component of the pressure force arises that presses the narrowed pipe against the dispensed pipe, and the soldering is very reliable.

Oh yeah, soldering iron stands. The classic one, on the left in the figure, is suitable for any rod. Where there are trays for solder and rosin on it is your business, there is no regulation. For low-power soldering irons with an apron, simplified brackets are suitable, in the center.

Correct and Incorrect Soldering Iron Stands

Soldering stations are equipped mainly with spring or tubular sockets for soldering irons. In them, the entire hot part of the tool is inaccessible to touch, but it is more likely to smear past them with a soldering iron, focusing on soldering a fine "scatter". But what certainly should not be done, and what is directly prohibited by TB, is a stand made of scrap materials, in which the soldering iron lies on the trays for consumables, on the right in Fig.

At a certain period, any person has a desire to learn how to learn how to solder with a soldering iron. It may be necessary to fix the contact in the outlet, or even fix it electrical circuit... Whatever the reason, this interest is fully justified.

With the help of a soldering iron, two metals are combined with the use of another metal with a significantly lower melting point.

Using a soldering iron in Everyday life has long been an ordinary event. The question of how to learn, most decides already in childhood. Soldering itself is a simple process, but it requires attention and accuracy.

Soldering process basics

Brazing is the process of joining two metals together using another metal that has a significantly lower melting point. The low-melting metal is called solder. The principle of any soldering is based on the heating of metals in the soldering zone to a temperature exceeding the melting point of the solder. In this case, the solder in the molten state flows into the gap between the metals and partially penetrates into their very structure. A mechanical connection and electrical contact between the metals to be soldered is provided.

Copper and copper alloys are well soldered with solder, steel, aluminum and other materials can be joined. Soldering large-sized elements is limited by the ability to warm them up to the desired temperature.

Tin-lead alloy with different tin content is usually used as a solder. The most applicable is the POS-40 and POS-60 grade solder (61), where the numbers indicate the percentage of tin in the solder. These solders melt at 235 and 183 ° C, respectively. POSV-33 grade tin-lead-bismuth solder is used, which melts at a temperature of 130 ° C. When soldering aluminum, it is necessary to use special aluminum solders, the melting point of which is much higher. Standard solder is sold in the form of rods or wires up to 2.5 mm in diameter.

For reliable soldering, it is necessary to clean the metal surface from oxide films. For this purpose, a flux is used. As a rule, rosin is used as a flux. During the soldering process, the flux also protects heated metals from exposure to air. In modern solders, rosin is included in their composition. Soldering can be carried out without flux, but then cleaning the surface with soldering acid is necessary. The flux can be used as a solution of rosin in alcohol. For complex rations, LTI-120 rosin is used.

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Copper and copper alloys are most easily soldered. The use of POS solder and rosin is sufficient. Silver and silver-plated products are usually brazed in the same way as copper, but to ensure best quality it is better to use a solder with a silver additive. Steel and galvanized metals are poorly soldered with rosin and require surface treatment with soldering acid. Nichrome, constantan and some other alloys (with high electrical resistance) are soldered using special fluxes. Nice results obtained when using aspirin as a flux. Soldering of aluminum and high-alloy steels with rosin is not possible. It is necessary to use special fluxes (for example, phosphoric acid) and solders.

Soldering of metals is carried out with a special heating tool - a soldering iron. A soldering iron consists of two main parts - a heater (usually a heating coil) and a soldering iron tip, as well as a handle and a cord for connecting to the mains. The heater is covered with a casing, and a copper sting is inserted and fixed inside it. In the heater, the entire tip is heated.

The main parameter of the soldering iron is its power. It determines the temperature and volume of the heated metal. Household soldering irons usually have a power rating of 25 to 100 watts. When repairing consumer electronics and radio engineering, soldering small wires using soldering irons with a power of 25-40 watts.

The entire soldering process is carried out with the tip of the tip, by touching which the metal is heated, the solder and flux melted, the solder is distributed over the metal surface. To quickly heat up and transfer heat to brazed metals, the tip material must have a high thermal conductivity, which causes the use of copper.

The shape and size of the soldering iron tip significantly affects the quality of the soldering. In terms of size, the sting is conditionally subdivided into a regular one, having a diameter of 4-5 mm, and a miniature sting, with a diameter of 2-3 mm. The miniature tip is used when soldering thin wires and very small copper parts.

In shape, the sting can be made in the form of a spatula, a cone, a needle, or a special shape for certain jobs. The most common sting is in the form of a spatula, beveled at 45º on one side or beveled on both sides (such as a screwdriver). In addition, the tip can be straight in length or curved at an angle for ease of soldering.

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Soldering preparation

In order to solder with a soldering iron, it is necessary to carry out certain preparatory work. First, you need to clean the surface of the metals on which the solder will be applied. For large parts, sanding is recommended. Cleaning from dirt, oils, fats is carried out with a solvent. Steel surfaces are cleaned with soldering acid.

The preparation of the soldering iron tip is important. The working surface of the tip must be flat, without sagging, cavities and other defects, and also have the shape provided by the design. If the tip of the tip has undergone deformation or partial melting, then use a file to return the desired shape and form a 45º bevel.

For high-quality soldering, it is advisable work surface stings to irradiate, i.e. cover with a thin layer of solder. To do this, you need to warm up the tip in a soldering iron, rub the working surface with rosin and dip it into the molten solder. The excess mass of solder should be removed by quickly moving a cloth over a hot surface or by rubbing the surface of the tip against wood.

To make it convenient to solder, you need to install the soldering iron in a position in which you can easily take it by hand and use it for its intended purpose. During operation, the soldering iron may heat up above 300 ° C; approaches him electrical voltage 220V - all this makes it necessary to optimize the place where the working soldering iron is located. For these purposes, a soldering iron stand is used. It can be standard, purchased, but usually it is made independently. A homemade stand can be in the form of a flat base on which two brackets are attached, bent so that a saddle is formed in the central part for installing a soldering iron.

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Soldering procedure

Connection of single-wire aluminum conductors by soldering a double twist with a groove: 1 - double twisting; 2 - a stick of solder; 3 - propane-butane burner.

Soldering is carried out in a specific order. The soldering iron prepared for soldering is installed on the stand and connected to the network. Soldering begins when the soldering iron tip reaches the required temperature. Typically, the heating time for a soldering iron is 5-6 minutes. During this period, it is necessary to correctly determine that the temperature of the tip has reached the desired value. A properly heated soldering iron (temperature 230-290 ° C) causes the rosin to boil and the solder melts evenly. If the temperature on the sting is insufficient (underheating), then the rosin only softens and melts slightly, and the solder acquires a mushy consistency. A significant excess of heating leads to splashing and hissing of the rosin, and the solder loses the elasticity of the melt. Such a soldering iron must be turned off and cooled a little.

The soldering process itself begins with the tinning of the surfaces to be soldered. To do this, a sting of a heated soldering iron, after placing it in rosin, is carried out over the metal surface to apply flux. Then, with the help of a tip, the molten solder is transferred and applied in a thin layer over the entire surface. To irradiate the wire, its end is pressed into molten rosin, and then a thin layer of molten solder is applied to it.

For soldering metals, the tin-plated surfaces are tightly pressed against each other. A hot soldering iron is brought to the place where the surfaces are combined and heated until the solder layer begins to melt and join the parts. The tip of the soldering iron is lowered into the molten solder, and an additional portion of the solder is transferred to the soldering area. The pressing of the surfaces to each other is maintained until the solder cools completely and hardens.

When soldering wires between themselves, their ends (pre-tinned) are recommended to be tightly twisted together beforehand. This will ensure reliable soldering contact. During soldering, the soldering iron is brought to the joint right hand, and with the left hand, the end of the solder wire is inserted into the soldering area. The molten solder is distributed with a soldering iron over the surface of the twisted wires so that the space between the twisted wires is filled with solder.

If the wires cannot be twisted, then they are soldered with an overlap, i.e. their ends are laid parallel to each other with pressure. In this case, one of the wires is held by the left hand and pressed against the second wire. The soldering iron is used to transfer the molten solder from the bath to the soldering area. The solder should fill the space between the wires. The wire is held by hand and after removing the soldering iron from the soldering zone, until the solder is completely solidified.

Butt soldering of wires is not performed, since it does not provide the required strength of the connection.

If it is necessary to solder a wire to the middle of another wire, then it is advisable to twist its end in the right place around the second wire. Soldering should be done in the same way as for twisted wires. In the case when there is no possibility of winding 2-3 turns, partial coverage of the surface of the second wire is provided, i.e. the wire is bent 180º around the second wire. With such soldering, the wire to be connected is held with one hand and it is securely pressed against the surface of the second wire, while the other hand is used to manipulate the soldering iron.

One of the most reliable ways to connect wires and parts is soldering. How to properly solder with a soldering iron, how to prepare a soldering iron for work, how to get a reliable connection - more on that later.

In everyday life, "ordinary" electric soldering irons are used. There are those operating from 220 V, there are - from 380 V, there are - from 12 V. The latter differ in their low power. They are mainly used in enterprises in premises with increased danger. They can be used for domestic purposes, but they are heated slowly, and the power is too small ...

You need to choose the one that fits comfortably in your hand

Power selection

The power of the soldering iron is selected depending on the nature of the work:

In a household, it is enough to have two soldering irons - one low-power - 40-60 W, and one "medium" - about 100 W. With their help, it will be possible to cover about 85-95% of the needs. And it is still better to entrust the soldering of thick-walled parts to a professional - specific experience is needed here.

Preparation for work

When the soldering iron is first plugged in, it often starts to smoke. This burns out the lubricants that were used in the production process. When the smoke ceases to stand out, the soldering iron is turned off, they wait until it cools down. Next, you need to sharpen the sting.

Sharpening the sting

Next, you need to prepare the sting for work. It is a cylindrical rod made of copper alloy. It is fixed with a clamping screw, which is located at the very end of the heat chamber. In more expensive models, the tip may be slightly sharpened, but, in general, there is no sharpening.

We will change the very tip of the sting. You can use a hammer (flatten the copper as needed), a file, or emery (just grind off what you don't need). The shape of the sting is chosen depending on the intended type of work. It can be:

• Flatten like a spatula (like a screwdriver) or flatten on one side (angled sharpening). This type of sharpening is needed if massive parts will be soldered. This sharpening increases the contact plane and improves heat transfer.
• It is possible to grind the edge of the sting into a sharp cone (pyramid) if it is supposed to work with small details(thin wires, electrical parts). This makes it easier to control the degree of heating.
• The same taper, but not as sharp, will work with larger conductors.

Sharpening with a "spatula" is considered more versatile. If it is formed with a hammer, the copper is compacted, the tip will need to be adjusted less often. The width of the "shoulder" can be made more or less by working it on the sides with a file or emery. With this type of sharpening, you can work with thin and medium soldered parts (turn the tip to the desired position).

Soldering Iron Tinning

If the tip of the soldering iron does not have a protective coating, it must be tinned - covered with a thin layer of tin. This will protect it from corrosion and rapid wear. They do this the first time the instrument is turned on, when the smoke has ceased to stand out.

The first method of tinning a soldering iron tip:

• bring to working temperature;
• touch the rosin;
• melt the solder and grind it along the entire tip (you can use a wooden chip).

Second way. Moisten a rag with a solution of zinc chloride, rub the heated sting against the rag. Melt the solder and rub it over the entire surface of the tip with a piece of common rock salt. In any case, the copper must be coated with a thin layer of tin.

Soldering iron technology

Almost everyone now uses electric soldering irons... Those who work with soldering prefer to have a soldering station, "amateurs" prefer to do with ordinary soldering irons without regulators. Having several soldering irons of different power is enough for different types of work.

To figure out how to properly solder with a soldering iron, you need to have a good idea of ​​the process in general, then delve into the nuances. Therefore, let's start with a brief description of the sequence of actions.

Soldering involves a sequence of repetitive actions. We will talk about soldering wires or radio technical parts. It is with them that we have to meet more often on the farm. Actions are as follows:

This completes the soldering. It is necessary to cool the solder and check the quality of the connection. If done correctly, the solder area has a bright sheen. If the solder looks dull and porous, this is a sign of insufficient temperature during soldering. The soldering itself is called "cold" and does not provide the required electrical contact. It breaks down easily - just pull the wires in different directions or even pick something up. Also, the soldering point may be charred - this is a sign of an inverse error - too high a temperature. In the case of wires, it is often accompanied by insulation melting. Nevertheless, electrical parameters are normal. But, if the conductors are soldered when the wiring is installed, it is better to redo it.

Soldering preparation

First, let's talk about how to properly solder wires with a soldering iron. First you need to remove the insulation. The length of the exposed area can be different - if you are going to solder the wiring, the power wires are exposed 10-15 cm. If you need to solder low-current conductors (the same headphones, for example), the length of the exposed area is small - 7-10 mm.

After removing the insulation, it is necessary to inspect the wires. If there is varnish or oxide on them, it must be removed. Freshly cleaned wires usually do not have an oxide film, and sometimes varnish is present (copper is not red, but brownish). Oxide film and varnish can be removed in several ways:

• Mechanically. Use fine grit sandpaper. The bare part of the wire is treated with it. This can be done with single-core wires quite large diameter... Sanding thin wires is inconvenient. Stranded so generally can be cut off.
• Chemical method. Oxides dissolve well with alcohol and solvents. Lacquer protective covering removed with acetylsalicylic acid (regular pharmacy aspirin). The wire is placed on a tablet, heated with a soldering iron. The acid eats away at the varnish.

In the case of lacquered (enameled) wires, you can do without stripping - you need to use a special flux, which is called "Flux for soldering enameled wires". He himself destroys the protective coating during soldering. Only so that later it does not begin to destroy the conductors, it must be removed after the end of soldering (with a damp cloth, sponge).

If you need to solder a wire to a metal surface (for example, a ground wire to a circuit), the preparation process changes little. The area to which the wire will be soldered must be cleaned to bare metal. First, all contaminants (including paint, rust, etc.) are mechanically removed, after which the surface is degreased with alcohol or solvent. Then you can solder.

Fluxing or tinning

When soldering, the main thing is to ensure good contact parts to be soldered. To do this, before starting soldering, the parts to be joined must be tinned or treated with flux. These two processes are interchangeable. Their main purpose is to improve the quality of the connection, to facilitate the process itself.

Tinning

To process the wires, you will need a well-heated soldering iron, a piece of rosin, and a small amount of solder.

We take the stripped wire, put it on the rosin, and warm it up with a soldering iron. While warming up, we turn the conductor. When the wire is all in molten rosin, we collect a little solder on the tip of the soldering iron (just touch the sting). Then we take out the wire from the rosin and run the tip of the sting along the bare conductor.

Tinning of wires is a mandatory step when soldering

In this case, the solder covers the metal with the thinnest film. If it is copper, from yellow, it becomes silver. The wire also needs to be turned a little, and the sting must be moved up / down. If the conductor is well prepared, it turns completely silvery, without gaps and yellow lines.

Flux treatment

Everything here is both simpler and more complicated. Easier in the sense that you only need a composition and a brush. Dip the brush in flux, apply a thin layer of the composition to the soldering point. Everything. This is the simplicity.

Difficulty in choosing a flux. There are many varieties of this composition and for each type of work you need to select your own. Since we are now talking about how to properly solder wires or electronic components (boards) with a soldering iron, we will give several examples of good fluxes for this type of work:

Do not use active (acidic) fluxes to solder electronic components (printed circuit boards). Better - water or alcohol based. Acidic ones have good electrical conductivity, which can disrupt the operation of the device. They are also very chemically active and can cause destruction of insulation, corrosion of metals. Due to their activity, they very well prepare metals for soldering, therefore they are used if it is necessary to solder the wire to the metal (they process the site itself). The most common representative is Soldering Acid.

Heating up and temperature selection

If you want to know how to properly solder with a soldering iron, you need to learn how to determine whether the soldering point is hot enough. If you use a conventional soldering iron, you can navigate by the behavior of the rosin or flux. With a sufficient heating level, they actively boil, emit steam, but do not burn. If the sting is lifted, droplets of boiling rosin remain on the tip of the sting.

When using a soldering station, proceed from the following rules:

That is, at the station we set it to 60-120 ° C higher than the melting temperature of the solder. The temperature gap, as you can see, is large. How to choose? Depends on the thermal conductivity of the metals to be soldered. The better it dissipates heat, the higher the temperature should be.

Solder application

When the soldering point is hot enough, you can add solder. It is introduced in two ways - melted, in the form of a drop on the tip of a soldering iron, or in solid form (solder wire) directly into the soldering zone. The first method is used if the soldering area is small, the second - for large areas.

If you need to add a small amount of solder, it is touched with a soldering iron tip. Solder is sufficient if the tip is white instead of yellow. If a drop is hanging - this is an overkill, it must be removed. You can tap the edge of the stand a couple of times. Then they immediately return to the soldering zone, holding the sting along the soldering point.

In the second case, we insert the solder wire directly into the soldering zone. When heated, it begins to melt, spreading and filling the voids between the wires, taking the place of the evaporating flux or rosin. In this case, it is necessary to remove the solder in time - its surplus also does not have a very good effect on the quality of the soldering. In the case of soldering wires, this is not so critical, but when soldering electronic elements on boards is very important.

In order for the soldering to be of high quality, everything must be done carefully: strip the wires, warm up the soldering point. But overheating is also undesirable, as is too much solder. This is where measure and experience are needed, and you can gain it by repeating all the actions a number of times.

Convenient soldering attachment - third hand

How to learn to solder with a soldering iron

First, take a few pieces of small diameter single-core wire (you can - installation wires, those that are used in communication, etc.) - it is easier to work with them. Cut them into small pieces and practice on them. Try to solder the two wires first. By the way, after tinning or processing with flux, it is better to twist them together. This will increase the contact area and make it easier to hold the wires in place.

When the soldering is reliable several times, you can increase the number of wires. They will also need to be twisted, but you will have to use pliers (two wires can be twisted by hand).

Normal soldering means:

After you have mastered the soldering of several wires (three ... five), you can try stranded wires... The difficulty lies in stripping and tinning. It will be possible to clean it only by a chemical method, and to tin it, having previously twisted the wires. Then you can try to twist the tinned conductors, but this is quite difficult. We'll have to hold them with tweezers.

When this is also mastered, you can train on wires of a larger cross-section - 1.5 mm or 2.5 mm. These are the wires that are used when laying wiring in an apartment or house. Here you can train on them. All the same, but it is more difficult to work with them.

After completing the soldering

If the wires were treated with acidic fluxes, after the solder cools down, its remnants must be washed off. To do this, use a damp cloth or sponge. They are moistened in solution detergent or soap, after - remove moisture, dry.

You know how to properly solder with a soldering iron, now you need to acquire practical skills.