Tin contacts. Soldering with a soldering iron at home

How to learn to solder. It was just such a small special lesson, not directly related to the main topic, that I decided to prepare for those who not only have to solder cords, sockets, plugs, but in general, anything. So, let's begin…

What do we need for soldering?

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

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

If you do not have a soldering station, which is initially ready for soldering immediately after turning it on, but an ordinary soldering iron, then before work (especially if it is new), you need to prepare it in a special way - tin it, otherwise it will not solder. What is it "to tin", now we will analyze.

How to tin a soldering iron?

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

After that, we lower the heated tip into rosin and immediately into solder (in tin). There will be almost no solder to stick to the sting, therefore, immediately after this procedure, we apply the sting to a small board, preferably of natural origin (not chipboard) better than spruce or cedar (resinous), but in principle any will do, only it will take longer to mess around.

So, we repeat this procedure (rosin → solder → plank) until the cut of the sting from yellow - with an overflow of bluish color of heated copper, prepared previously with a file, becomes silvery and shiny from the solder covering it evenly. This is what is called "tinning", in this case a soldering iron.

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

Now we will learn how to solder the wiring (previously, by tinning it) to a brass tin, also tinning it from the beginning.

We dip the tip of the soldering iron into the rosin, then into the solder, and immediately, with the plane of the tip parallel to the plane, we bring it close to our brass guinea pig, not allowing the rosin to evaporate, we press it, then we grind it, we crawl, in general - we tinker. If the rosin has evaporated or spread, we repeat the process, and gradually, gradually, our tin is covered with solder adhering to it with high quality. If the material is clean or without strong oxides, then such tinning occurs quickly.

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

How to tin a wire?

Now we're tinkering with the wiring. We carefully remove the insulation just enough so that we have enough space for soldering, and for the location of the heat shrink tube, (or other insulator) so that later there are no “shorts” (short circuits) ...

The wire is easier to tinker, because. usually, under insulation, the metal is clean, not oxidized. We dip it into rosin, putting the tip of a heated soldering iron on top of it, and slowly pull the wire out from under the soldering iron after the rosin melts and smokes. This is done, as they probably understood, in order for the molten rosin to wrap around the contact part of the wire. Now we enrich the soldering iron tip with solder, touching the tin, bring the tip to the rosin adhering to the wiring.

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

If not, then you may have to repeat the operation or use solder paste instead of rosin - a special chemical substance (such as soldering acid, if anyone is familiar) that allows you to tin, for example, even iron.

This is what solder paste looks like.

How to solder a wire?

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

We bring a soldering iron tip enriched with solder to the place of their contact so that the solder covers the tinned parts of the soldered parts with high quality. The rosin involved in the process will contribute to this. If something doesn't work out, dunk it in. After the parts are in the molten solder, try not to move them anymore. You can lightly blow on the soldering place until the solder shine slightly darkens, which will indicate that the soldering has solidified.

Everything, congratulations! You succeeded.

How to solder a wire?

It is possible to unsolder wires and various soldered joints, respectively, by the reverse method - by heating the place of soldering (tinned and dipped in rosin, heated) with a soldering iron tip until the solder melts.

... And, probably, the final touch - you can still dip a small paint brush into the solvent and rinse the remaining rosin in the soldering points.

What can be soldered?

More specifically, what metals are good for soldering? In the first place, it is, of course, copper, brass, gold, silver, lead, of course - tin. It is worse to solder (tin) iron, steel, zinc. To tin the latter, you will have to use a special solder paste (see the figure above). There are some metals that cannot be soldered at all, for example, aluminum.

This week, my family and I almost fell victim to dementia and courage. And it is not easier that someone else.
Yes, in home power wiring at 230V, the ends of a stranded wire are not recommended to be tinned. Compression is recommended. And what happens if you still tin it and leave it like that? So I became a victim of the experiment, without knowing it.

A lamp has been hanging in the kitchen for many years - here it is on trial, after repair and without a lampshade.

And then on Friday, the light began to blink suspiciously. Installed another one, same thing. It's not about the light bulb. Opened the switch, sniffed, listened. Doesn't sparkle. He removed the lamp from sin, hung up a temporary hut - a cartridge with a wire. At the same time I looked at the connection - everything is fine, through the terminal, the wires are not burnt.

Saturday got busy. Let's look at the cartridge. Yes, there is slight damage to the contacts - but everything is within the permissible range for many years.


But somewhere sparks! We disassemble further - only the cartridge remains, connected to the wire at the factory.


And there…


These brown semi-charred pieces are cut off from the same wire, the other ends of which are crimped higher. It can be seen that the blue also turned brown. The flexibility of the insulation is completely lost. It has become brittle - it cracks and falls off, exposing the copper vein.

And here is the reason. The wire ends are tinned at the factory.

I'm lucky. The picture of burning plastic dripping from the ceiling remained in nightmares. But it became clear exactly how he could punish. For years, the tinned end will hang with a cocked trigger, and then it may shoot.

Crimp the tips. And watch out for electricians. Who know that it will do anyway - to drive with shameful rags.

For some reason, I dumped this text on the muse. Where they explained to me in a crowd that they were playing, we are playing and we will play. And squeeze retrogrades. So I quickly took it out. That is, with everyone who tips the power wires and will play tricks - I agree, please. KSSZB. And the traffic light blinks red foolishly, and the brakes were invented by cowards. And here, too, I agree and will not argue. But I still want to warn innocent people.

I will add that this circular is very close to the topic. It is not about tinning, more broadly, about soldering in general. But the physics remains





- difficulties in ensuring normal sanitary and hygienic conditions when making connections during installation, etc.

ASSOCIATION "ROSELECTROMONTAZH"

TECHNICAL CIRCULAR

Moscow 2012
ON THE APPLICATION OF SOLDERING IN ELECTRICAL CONNECTIONS

Non-separable wire connections, in accordance with the requirements of regulatory documents, can be made by crimping, welding or soldering.

In accordance with the guidelines of GOST R 50571-5-52-2011 (IEC 60364-5-52:2009), connections between conductors and between conductors and other equipment must ensure electrical continuity and adequate mechanical strength and protection, and when choosing means of connection, consideration should be given to :

The material of the conductor and its insulation;

The number and shape of the wires forming the conductor;

Conductor cross-sectional area;

The number of conductors to be connected together.

At the same time, regulatory documents and reference materials form the following relation to the use of soldering in electrical installation technology:

Clause 7.8.3.2 GOST R 51321.1-2007: “There should be no twists or solder joints on the conductors connecting two adjacent devices”;

Clause 7.8.3.5 GOST R 51321.1-2007: “Connection of conductors to equipment using soldering is allowed only in cases where this type of connection is provided for in the regulatory documentation for the low-voltage switchgear”;

Note to clause 526 of GOST R 50571-5-52-2011 (shall be enforced from 01/01/2013) “Low-voltage electrical installations. Part 5. Selection and installation of electrical equipment. Chapter 52. Wiring": "The use of solder connections is recommended to be avoided, with the exception of communication circuits. If such connections are used, they must be made taking into account possible displacements, mechanical stresses and temperature rise during short circuits (see 522.6, 522.7 and 522.8)”;

Clause 4.2.46 of Chapter 4.2 of the Electrical Installation Code: “The connection of flexible wires in spans should be carried out by crimping using connecting clamps, and connections in loops at supports, connecting branches in a span and connecting to hardware clamps by crimping or welding. In this case, the connection of branches in the span is performed, as a rule, without cutting the wires of the span. Soldering and twisting wires are not allowed.

The indications of the cited documents actually limit the use of soldering in the connections of electrical conductors due to the presence of significant drawbacks of such a connection method.

The disadvantages of compounds containing tin-lead solders include:

Reduced electrical conductivity and mechanical strength;

Increasing transitional resistance over time;

Chemical corrosion caused by flux residues;

Environmental insecurity;

Difficulties in ensuring normal sanitary and hygienic conditions when making connections during installation, etc.

In accordance with the guidelines of GOST R 50571-5-54-2011 (IEC 60364-5-54:2002), an additional requirement is imposed on the connections of grounding conductors, which consists in the fact that the connection of conductors or fittings by soldering is possible only if there is a reliable mechanical fixation .

The specified requirement must first of all be implemented when making contact connections of class 2 according to GOST 10434-82 * in the circuits of grounding and protective conductors (see clause 1.7.139 of the seventh edition of the Electrical Installation Code).

This requirement is a consequence of the instructions of clause 2.2.6 of GOST 10434-82 * “Contact connections”: “After the through current mode, the contact connections should not have mechanical damage that prevents their further operation. The temperature of contact connections in the through current mode should not exceed 200 °C for connections of conductors made of aluminum copper, aluminum and its alloys, as well as for connections of these conductors with copper, 300 °C - for connections of copper conductors and 400 °C - for connections of steel conductors." When connecting copper conductors, the permissible connection temperature can reach 300 ° C, which exceeds the melting point of soft solder. Without additional mechanical fastening of the conductors before soldering, it is not possible to ensure the quality of a non-separable contact connection.

Most often, a bandage is used to perform mechanical fastening of conductors before soldering. The Instructions for the installation of electrical equipment, power and lighting networks in explosive zones VSN 332-74 and the Manual for the implementation of electrical installations in explosive zones, still used by installation organizations, provide several ways to connect grounding conductors with armor and metal sheaths of cables using soft soldering . These documents provide connection methods where additional mechanical fastening of conductors is performed after soldering or not performed at all. This is not in accordance with the instructions of the current regulatory documents. When performing a mechanical connection using a bandage with subsequent soldering, when the solder is melted in the through current mode, it does not drain. After the fault current is switched off, the contact connection is mechanically restored.

The issue of connecting a stranded core to equipment terminals and connectors deserves special attention. The requirements for tinning stranded wires with tin-lead solders in collapsible electrical contact joints of wires and cables are set out in clause 2.1.8 of Table. 5 GOST 10434 edition of 1982. However, it is necessary to take into account the fact that modern clamps, in contrast to those given in GOST 10434-82, as a rule, have a socket design in which the stranded conductor core is not squeezed out, is not squeezed out from under the screw head or washer, but, on the contrary, crimped, pressed in a structurally limited section of the clamp. Soldering the ends of stranded wires into a monolith is not required in this case. It should also be borne in mind that GOST 10434-82 applies to currents from 2.5 A. For contact connections of electrical devices for currents less than 2.5 A, the requirements of the standard are recommended.

Manufacturers of connectors widely used in the domestic market: Schneider Electric, Phoenix Contact, Wago, Weidmüller, etc., deny the need for embedding (soldering) a stranded core before making a connection.

The purpose of this circular is to provide specific recommendations for making electrical connections by soldering:

1. The use of solder joints in electrical installations should be avoided. If such connections are used, they must be made taking into account possible displacements, mechanical stresses and temperature rise during short circuits.

2. Soldered joints should in any case not be used in places subject to displacement, vibration and shock.

3. When making an electrical connection of the armor or metal sheath of the cable with the connected equipment, it is allowed to solder the grounding or protective conductors of potential equalization with soft solder, for example, POS-40, without unwinding the cable armor with mechanical fastening of the conductor to the armor using a bandage.

4. In demountable connections, the compatibility of the stranded conductor core with the corresponding clamps of the devices and connectors must be ensured. In this case, the requirement that the stranded core be sealed by soldering, as well as crimping with a sleeve, which increases the transition resistance, is redundant and degrades the operational reliability of modern collapsible connections.

Working with radio electronics involves soldering materials. It is easy to learn this, and if there are incomprehensible nuances, then with experience they will disappear. The tool requires maintenance for its quality work. The master needs to be able to correctly tin the soldering iron tip so that the solder holds. The tool must not be damaged. The quality of soldering depends on the correct actions when processing the base.

Coating features

Simple type soldering irons traditionally have a copper tip. The material has been used ever since the invention of the tool due to its high thermal conductivity. But there is a drawback - the ability to high wear. Copper burns out or dissolves in the solder. The shortcoming had to be eliminated, and manufacturers began to apply an additional coating of nickel or silver.

Nickel has high strength and does not wear out. Long service life is the advantage of nickel plating. The disadvantage is poor adhesion. Such a tip does not hold solder well. Soldering can be performed only when solder is supplied directly to the work area. The working area is heated with a sting, then a small part of solder or solder paste is placed. Seizure comes from heat.

Silver has good adhesion, but is a poor conductor of heat. In addition, the material is expensive. Over time, the silver wears out and exposes the copper base. This is because the silver coating dissolves into the solder.

Spraying features complicate operation and maintenance. Therefore, radio amateurs, especially the older generation, prefer copper soldering irons. But the copper sting has a drawback - hot copper instantly oxidizes. Interaction with air occurs only on a thin layer, but this is sufficient for zero adhesion. Heat is also transferred worse. Way out - the tip should always be covered with a thin layer of solder.

Tin should not be applied before soldering, because copper begins to burn out under its layer. At the burnout site, slags appear, due to which there is no adhesion. The master begins to be distracted from work.

Abrasive materials wear down the coating. Nickel or ceramic is applied in a thin layer on the tip - that's why you can't grind them down. An expensive tip will turn into a copper bar.

The process of preparing a copper sting

The coating process is not difficult. Molten solder fits well on hot copper, but with one condition - it must be clean. This can only be achieved at low temperatures. Oxidation accelerates with increasing temperature and adhesion disappears. Cold solder cannot be stuck to the tip because it does not melt. It turns out a vicious circle.

Slag, rosin and plastic residues, scale and other debris can be removed on a cold tool. The rod is pulled out before this operation so as not to damage the heater. The sting inside the heater also oxidizes, which impairs heat transfer. Electricity due to scale overcomes excess resistance and is wasted.

Before you tin a soldering iron with a copper tip, it must be cleaned of dirt. Do it with a file or sandpaper. The material should be sharpened to a clean layer so that the appearance is like new. It's easier to do it with sandpaper. The surface is polished to a smooth state - so the oxidation is slower.

The rate of oxidation can be reduced by binding the sting. Do it with a hammer on an anvil. With gentle blows, they strengthen the surface and give shape to the copper bar. Next, they proceed to the tinning process until it is covered with slags.

Methods for tinning a copper sting:

Proper preparation will allow you not to be nervous at the initial stage of work. After a while, the process needs to be redone due to the fact that copper begins to oxidize.

Tinning of modern coating

Ceramic and nickel tips do not need to be tinned. Manufacturers read this way, but this is nothing more than advertising. Modern coatings are also prone to oxidation, only the process is slower. Tinning the soldering iron tip of a modern type soldering station in the usual way will not work - the coating will be erased.

Cleaning is carried out with a wet cloth from cotton fabric. They take hard rosin, where they put a little solder. The tip should be rubbed with a cloth and immediately dipped in rosin. A piece of solder is recessed vertically down. The solder melts and wraps around the cone of the tip.

Cleaning during operation

Correctly irradiating the soldering iron is important not only during preparation for work. After some soldering time, it may happen that the material does not stick to the base again. This happens after 15 minutes. Copper burns under a layer of tinning. There are several ways to properly tin a soldering iron while working.

block of wood

An unhewn block of wood should always be at the hand of the master. Conifers are used, since such wood has natural rosin. I pour flux on the wood and put a little solder. As soon as scale appears on the sting, rub it against the tree. During this process, the base is cleaned and tinned.

metal sponge

The method of instant tinning the base of the soldering iron. Factory soldering machines are equipped with a similar device in the form of a steel sponge in a container.

It is convenient for the master to use this method, but it can be improved. The bottom of the sponge is smeared with flux - soldering fat. With a shallow immersion of the sting, it will simply be cleaned. And if you apply solder to the base and dip it deep, to the base of the sponge, then cleaning will be combined with tinning.

The method is optimal for modern tips with ceramic or nickel coating. Even soldering irons with a thin copper tip can be cleaned and tinned this way. Damage to the device is difficult to cause even with strong pressure.

The use of rosin

A method for a traditional tool with a simple copper tip. The metal quickly oxidizes and after 10-15 minutes the solder can no longer be picked up. If you clean it separately from the flux, then the master will not have time to bring the soldering iron - oxidation passes so quickly.

Clean the instrument because of this in rosin. A file is placed under the soldering iron, you can use steel wire. Then rub with a sting until the flux melts. Solder should not be.

Classical method and prevention

The previous methods were invented by the master relatively recently. Our ancestors, even our fathers, did tinning a little differently. This required a file with a fine notch., a workbench for work (can be replaced with a board), rosin and the most refractory solder.

Procedure:

The procedure will take 10 minutes, no less. A large amount of preparation time is paid off by the fact that you can work with the tool for several days without much preparation.

Working for a long time will cause overheating. An increase in temperature increases the oxidation and the rod has to be prepared for work more often. In order to avoid unnecessary procedures, you should follow some rules.

Preventive measures against oxidation:

The tool must always be kept ready. After a long period of inactivity, the soldering iron tip is not tinned due to strong oxidation. Restoring the adhesion of the coating, especially from copper, is carried out with rosin. After immersion in it, the sting is rubbed with a cotton cloth. During operation, the soldering iron also needs to be cleaned periodically.

Soldering with a soldering iron- This is a physico-chemical technological operation for obtaining a permanent connection of metal parts by introducing a metal with a lower melting point into the gap between them.

Soldering with a soldering iron is much easier than it seems at first glance. The technology of soldering with a soldering iron was successfully used by the Egyptians 5 millennia ago and little has changed since then.

The requirements for the technological process of soldering and mounting of radio elements are set out in OST 107.460092.024-93 “Soldering of electrical connections of radio electronic equipment. General requirements for typical technological operations.

The process of soldering with a soldering iron begins with the preparation of the surfaces of the parts to be soldered. To do this, it is necessary to remove traces of dirt, if any, and an oxide film from the surfaces. Depending on the thickness of the film and the shape of the surface, it is cleaned with a file or sandpaper. Small areas and round wires can be stripped with a knife blade. The result should be a shiny surface without stains of oxides and shells. Fat contamination is removed by wiping with a cloth soaked in acetone or white spirit solvent (purified gasoline).

After preparing the surfaces, they must be covered with a layer of solder and tinned. To do this, flux is applied to the surface and a soldering iron tip with solder is applied.

For better heat transfer from the soldering iron tip to the part, you need to apply the tip so that the contact area is maximum. The cut of the tip of the soldering iron with solder should be parallel to the surface of the part.

The most important thing when soldering with a soldering iron is to heat the surfaces to be soldered to the temperature of the molten solder. With insufficient heating, the soldering will turn out to be matte with low mechanical strength. When overheated, the solder will not spread over the surface of the parts to be soldered and soldering will not work at all.

After completing the above preparation, the parts are applied to each other, and soldering is performed with an electric soldering iron. The soldering time, depending on the thickness and weight of the parts, is from 1 to 10 seconds. Many electronic components allow a soldering time of no more than 2 seconds. As soon as the solder spreads evenly over the surfaces of the parts, the soldering iron is retracted to the side. The displacement of parts relative to each other until the solder is completely solidified is not permissible, otherwise the mechanical strength and tightness of the solder will be low. If this happens by accident, then you need to redo the soldering procedure.

Solder on the tip of a hot soldering iron, while waiting for soldering, is covered with oxides and residues of burnt flux. Before soldering, the tip must be cleaned. For cleaning, it is convenient to use a moistened piece of foam rubber of any density. It is enough to quickly draw a sting over the foam rubber and all the dirt will remain on it.

Before soldering, surfaces or wires that are connected by soldering must be tin-plated without fail. This is a guarantee of the quality of the solder joint and the enjoyment of work. If you do not have experience with a soldering iron, then before performing critical soldering work with a soldering iron, you first need to practice a little. It is easier to start with a single-core copper wire, which is how electrical wiring is made. The first step is to remove the insulation from the conductor.

How to tin copper wires

When the insulation is removed, you need to evaluate the condition of the conductor. As a rule, in new wires, copper conductors are not covered with oxides and can be tinned without stripping. It is enough to take a little solder on the tip of the soldering iron, touch it with rosin and move the tip along the surface of the conductor. If the surface of the conductor is clean, then the solder will spread over it in a thin layer.

If there is not enough solder, then an additional portion is taken with a touch of rosin. And so on, until the entire conductor is completely tinned. It is more convenient to tin wires by placing them on a wooden platform, which I use as a soldering iron stand. Usually, in the place where I always puddle, rosin accumulates and the process goes faster, you can grab more solder without touching it, once again with a rosin sting.

Sometimes, contrary to expectations, although the conductor seems to be without oxides, it does not want to be tinned. Then I put it on an aspirin tablet and warm it up for a couple of seconds, and then I puddle on the site. Luditsya immediately without problems. Even a copper wire with obvious oxidation, without preliminary mechanical stripping, with aspirin immediately breaks with a thin layer of solder.

If you managed to tin the conductors with a soldering iron, as in the photo, then congratulations on your first successful soldering job.

It is difficult to get good soldering with a soldering iron the first time. There may be several reasons for this. The soldering iron is too hot for this type of solder, this can be determined by the rapidly forming dark film of oxides on the solder, which is located on the tip of the soldering iron. With excessive heating of the soldering iron tip, the working blade of the tip is covered with black oxide, and the solder is not retained on the tip. The temperature of the soldering iron tip is not sufficient. In this case, the soldering is loose and looks matte.

Only the use of a temperature controller can help here. Insufficient heating of the wire during tinning occurs with a small amount of solder on the working part of the tip. The contact area is small, and the heat is poorly transferred to the conductor. You need to practice until you can tin the wires as in the photo above.

After tinning the wire with a soldering iron, excess solder often remains on it in the form of sagging. In order to get a thin and even layer, you need to place the wire vertically, end down, the soldering iron vertically with the tip up, and draw the tip along the wire. The solder is heavy and all will go to the tip of the soldering iron. Just before this operation, you need to remove all the solder from the tip by hitting it lightly on the stand. In this way, you can remove excess from the place of soldering and on printed circuit boards.

The next stage of training is to solder a stranded copper wire with a soldering iron, the task is somewhat more difficult, especially if the wire is covered with oxide. It is difficult to remove the oxide film mechanically; you need to unwind the conductors and clean them individually. When I thermally removed the insulation from the wires, I found that the upper conductor was covered with oxide, and the lower conductor was unraveled. This is perhaps the most difficult case for tinning. But they are tinned with the same ease as single-core ones.

The first thing you need to do is put the conductor on an aspirin tablet and move it with a soldering iron so that all the conductors of the wire are wetted with the aspirin composition (when heated, aspirin melts).

Next, tin on the site with rosin, as described above, with the only difference being that you need to press the wire with the tip of the soldering iron to the site and, during the tinning process, rotate the wire in one direction so that the conductors intertwine into a single whole.

These are the copper wires after tinning.

From such an end of a tinned wire, it is possible to form a ring with the help of round-nose pliers, for example, for threaded connection to the contacts of a socket, switch or chandelier cartridge, or solder to a brass contact or a printed circuit board. Try to make such soldering with a soldering iron.

The main thing when connecting parts by soldering is not to move them relative to each other until the solder has hardened.

Soldering any parts with a soldering iron is not much different from soldering wires. If you managed to tin and solder a stranded wire with high quality, then you can perform any soldering.

How to tin a very thin enameled copper conductor

It is easy to tin with a soldering iron a thin conductor, with a diameter of less than 0.2 mm, insulated with enamel, if you use vinyl chloride. Insulating tubes and the insulation of many wires are made from this plastic. You need to put the wire on the insulation and lightly press it with the tip of the soldering iron, then drag the wire through, turning each time. From the heating of vinyl chloride, chlorine is released, which destroys the enamel and the wire is easily tinned.

This technology is indispensable when soldering with a soldering iron a wire of the licendrat type, which is a lot of thin wires coated with enamel and twisted into one conductor.

With the help of an aspirin tablet, it is also easy to tin an enameled thin wire with a soldering iron, in the same way the wire is pulled between the aspirin tablet and the soldering iron tip. There should be a sufficient amount of solder and rosin on the tip.

Soldering radio components with a soldering iron

When repairing electrical appliances, it is often necessary to solder radio elements from the printed circuit board and solder them back. Although this operation is not difficult, it still requires compliance with a certain soldering technology.

Soldering with a soldering iron resistors, diodes, capacitors

In order to solder two output radioelement from the printed circuit board, for example, a resistor or a diode, it is necessary to heat up the place of its soldering with a soldering iron until the solder melts and pull the radioelement output out of the board. Usually, the output of the resistor is removed from the printed circuit board by prying it over the output with tweezers, but the tweezers often slip off, especially if the output of the radio element on the solder side is bent.

For the convenience of work, the tweezer sponges need to be sharpened a little, the resulting grip will prevent the tweezers lips from slipping.

When dismantling radio elements, one more hand is always missing, you need to work with a soldering iron, tweezers and still hold the printed circuit board.

As a third hand, I use desktop tesks, with the help of which a section of the printed circuit board free from details can be clamped, and by placing a vise on any side face, orient the printed circuit board in three dimensions. Soldering with a soldering iron will be convenient.

After soldering the part from the board, the mounting holes are filled with solder. It is convenient to free the hole from the solder with a toothpick, a sharply sharpened match or a wooden stick.

The tip of the soldering iron melts the solder, the toothpick is inserted into the hole and rotates, the soldering iron is removed, after the solder has solidified, the toothpick is removed from the hole.

Before installing a new radio element for soldering, it is imperative to make sure that its conclusions are solderable, especially if the release date is not known. It is best to simply tin the leads with a soldering iron and then solder the element. Then the soldering will turn out to be reliable and the work will be a pleasure, not a torment.

How to solder SMD LEDs and other leadless components

Currently, leadless SMD components are widely used in the manufacture of electronic devices. SMD components do not have traditional copper wire leads. Such radio elements are connected to the tracks of the printed circuit board by soldering contact pads to them, located directly on the component case. Soldering such a component is not difficult, since it is possible to solder each contact individually with a low-power soldering iron (10-12 W).

But when repairing, it becomes necessary to desolder the SMD component to check or replace them, or desolder from an unnecessary printed circuit board for use as spare parts. In this case, in order not to overheat and break the component, it is necessary to simultaneously warm up all its outputs.

If you often have to desolder SMD components, then it makes sense for the soldering iron to make a set of special tips, branching at the end into two or three small ones. With these tips, desoldering SMD components will be easy without damaging them, even if they are glued to the PCB.

But there are situations when there is no low-power soldering iron at hand, and in the existing powerful soldering iron, the tip has become attached and it is impossible to remove it. There is also a simple way out of this situation. You can wind a copper wire with a diameter of one millimeter around the soldering iron tip, as in the photo. Make a kind of nozzle and use it to successfully solder SMD components. The photo shows how I soldered SMD LEDs when repairing LED lamps. LED housings are very delicate and practically do not allow even small mechanical impacts.

If necessary, the nozzle can be easily removed and you can use the soldering iron for its intended purpose. The width between the ends of the nozzle can be easily changed, thereby adjusting different sizes of SMD components for soldering. The nozzle can be used instead of a low-power soldering iron, soldering small parts and soldering thin conductors to LED strips.

How to solder an LED strip with a soldering iron

The technology for soldering LED strips is not much different from soldering other parts. But due to the fact that the PCB substrate is a thin and flexible tape, soldering time should be kept to a minimum to avoid delamination of the printed tracks.

Repair of the iron car body by soldering

In the old days, when I drove a Soviet car, the technology of soldering iron with a soldering iron helped out when eliminating corrosion of the car body. If you just clean the place covered with rust and apply a paint and varnish coating, then after a while the rust will appear again. Having covered the cleaned place with a soldering iron with a thin layer of solder, rust will never appear again.

I had to solder with a soldering iron and through corrosion holes in the sills and the zone of the wheel arches of the car body. To do this, you need to clean the surface around the hole with a strip of one centimeter and tin with solder with a soldering iron. From thick paper, cut out a pattern for a future patch. Next, along the pattern of brass with a thickness of 0.2-0.3 mm, cut out a patch and the area that will be soldered, tin with a soldering iron with a thick layer of solder. If necessary, the patch is given the desired shape. You can simply tap the patch by placing it on a thick, dense rubber. File the edges of the outer side of the patch to nothing. It remains to attach a patch to the hole in the body and warm it well with a hundred-watt soldering iron along the seam. Puttying, priming, painting, and the body will be like new, while rusting in the repaired place will never happen again.

During repair, modernization or when installing electrical wiring, special attention is paid to the quality of the connection of conductive cores. Reliable soldered connections are the key to the safe operation of electrical mains and household appliances. To fix the solder well, it is necessary to pre-irradiate the wires, the essence of the procedure is to cover the surface with tin.

Why is wire tinning so important?

Tinned wires prevent oxidation

Before you tin the wire, you need to find out why this procedure is so necessary. Copper and aluminum, when interacting with oxygen, oxidize, forming an oxide film on their surface, which worsens conductivity and increases resistance. Tinned wires avoid this. The wires are tinned with lead-tin solders, their advantage lies in a long service life, safety and reliability.

Also, tinning is used during soldering, for example, when connecting LED strips to a power supply. If the cores of the lighting device are not pre-irradiated, over time all the wiring will fall off.

Soldering the wire with a soldering iron

Tinning wires with a soldering iron

For quality work, it is important to confidently own a soldering iron. If there are no fixed skills, it will not be possible to tin and solder the wire.

There are different models of soldering irons, each has its own technical characteristics - power, dimensions, etc. A novice master is recommended to give preference to soldering stations, where it is possible to regulate the heating temperature on their own.

It is advisable to purchase an expensive device, since the process will take less time, and the work will be done in joy.

Required Tools

Flux is selected depending on the material of the wire

Installation, modernization, repair and maintenance of wires is troublesome, but not difficult. To reduce the time spent, pre-prepare all the necessary tools and consumables for work. The list looks like this:

• consumables include solder and flux;
• sharp knife;
• soldering station or soldering iron;
• technical or medical tweezers;
• ordinary pliers.

You can use not a well-sharpened knife, but special pliers that allow you to remove the entire insulating layer with a few movements. But their cost is quite high, so many use a knife or scalpel.

In each case, a specific solder and flux composition for cables is required, this must be taken into account.

Procedure

To irradiate the wire, you need to act according to the following algorithm:

1. Using a special tool, a knife or a scalpel, remove the insulating layer from the wires that need to be connected.
2. After removing the insulating material, strip the conductive wires until a characteristic sheen is formed. To do this, you can use a knife or sandpaper. If the work is to be done not with a cast core, but with a stranded wire, each posting is fluffed up and stripped separately.
3. The soldering iron is plugged into the outlet and cleaned of all the contaminants that he likes to collect, especially old solder and dust. When cleaning the core of the soldering iron, it is recommended to use a small sandpaper.
4. It is required to warm up the tip of the wire. This can be done with a soldering iron, a gas burner, or a regular lighter.
5. When the soldering iron has warmed up to operating temperature, its core is touched by solder and rosin. The working surface should be abundantly covered with melted tin.
6. The next step is to touch the copper conductor with a hot soldering iron. The solder should be evenly distributed over the core. To apply solder, pliers and tweezers are used.
7. At the end of the work, the cable or wire is carefully inspected. The work surface must be completely and evenly covered with solder. Empty cavities or accumulations of material must be absent. If defects are found in the work, the procedure is started again.

If you have to work with very thin wires, it is better not to use rosin, since it is very difficult to calculate the exact amount of the substance. Soldering acid is suitable as an analogue. You can process the tip of the conductor with an ordinary brush. After that, you can start applying solder. This method cannot be called more reliable, but with such types of wiring it is impossible otherwise.

Wire Processing Methods

Tinning with a wooden block

There are several ways to tin. Some masters prefer the method, the essence of which is to press the wires with a soldering iron to a wooden flat surface.

When heated, gases are released from the wood, which act as a flux, helping to remove oxides on the metal.

It is possible to remove the oxide film on the surface of conductive wires more efficiently with the help of aspirin. During operation, the tablet is placed under the wires. When heated, gases are released from acetylsalicylic acid, enveloping the junction, displacing impurities from them that adversely affect the quality of the connection. This simple and cost-effective method provides high-quality tinning.

There is another way to prepare multi-core cables and wires, in which the copper base is covered with enamel. It is preferable to use a small piece of PVC material as a substrate. Under thermal exposure, PVC begins to actively release hydrogen chloride, which effectively destroys the oxide layer.

Tinning by dipping

If you have to work with wires and cables of large diameter, then it is advisable to prepare differently. Complete and uniform distribution of solder in this case is not easy to achieve.

There is a special device - a crucible, in which small pieces of tin are placed. There they are heated, resulting in a molten metal. The end of the wire is pre-immersed in rosin or other brands of flux, and then into the crucible container. This approach ensures a complete and uniform distribution of substances at the cut site.

This method can only be used with fully tinned wires. Diving already has a completely different scale, and is carried out in an industrial environment. The process is implemented using a special coil with a wound wire. First, the entire copper surface is manually treated with hard brushes, their bristles are pre-treated with liquid zinc chloride. Dissolved flux is obtained from a mixture of technical hydrochloric acid and zinc.

Next, the wire from the coil is slowly untwisted and dipped into a container filled with dissolved tin. The uniformity of the coating is ensured by secondary processing of the cable or wire of large diameter with rubber brushes. Finally, the cable is immersed in a container of cold water and brushed again. After that, the wires and cables are wound and packaged for further sale in hardware stores.