Any person at a certain period has a desire to learn how to learn how to solder with a soldering iron. Perhaps it became necessary to fix the contact in the socket, or even fix the electrical circuit. Whatever the reason, such an interest is fully justified.
Using a soldering iron, the joining of two metals takes place with the use of another metal having a much lower melting point.
The use of a soldering iron in everyday life has long become an ordinary event. The question of how to learn how to solder a soldering iron, the majority decides already in childhood. Soldering itself is an easy process, but it requires attention and care.
Basics of the soldering process
Brazing is the process of joining two metals using another metal that has a much lower melting point. Fusible metal is called solder. The principle of any soldering is based on the heating of metals in the soldering zone to a temperature above 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 the structure itself. Mechanical coupling and electrical contact between soldered metals is ensured.
Solder copper and copper alloys are well soldered, it is possible to combine steel, aluminum and other materials. The soldering of large-sized elements is limited by the ability to heat them to the desired temperature.
Scheme of capillary soldering of copper.
A tin-lead alloy with different tin contents is commonly used as a solder. The most applicable is solder brand POS-40 and POS-60 (61), where the numbers indicate the percentage of tin in the solder. These solders melt at 235 and 183 ° C, respectively. It uses the tin-lead-bismuth solder of the brand POSV-33, which melts already at a temperature of 130ºС. When soldering aluminum, it is necessary to use special aluminum solders, the melting point of which is much higher. Standard solder is realized in the form of rods or wire with a diameter of up to 2.5 mm.
For reliable soldering, it is necessary to clean the metal surface from oxide films. For this purpose, 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 solder rosin is included in their composition. Brazing can be carried out without flux, but then cleaning the surface with soldering acid is necessary. Flux can be used in the form of a solution of rosin in alcohol. For complex rations, rosin brand LTI-120 is used.Back to table of contents
Councils of masters: features of soldering of different metals
The procedure for the soldering of copper pipes.
Copper and copper alloys are most easily soldered. Enough use of solder pic and rosin. Silver and silver-plated products are usually brazed in the same way as copper, but to ensure the best quality, it is better to use 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. Good results are obtained when using aspirin as a flux. Soldering of aluminum and high-alloyed steels with rosin is impossible. It is necessary to use special fluxes (for example, phosphoric acid) and solders.
Soldering of metals is carried out by a special heating tool - a soldering iron. The soldering iron consists of two main parts - a heater (as a rule, a heating coil) and a soldering tip, as well as handles and a cord for connection to the electrical grid. The heater is closed by a casing, and a copper sting is inserted and fixed inside. The heater provides heating of the entire sting.
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 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.
Soldering soldering tip.
The whole process of soldering is carried out by the tip of the tip, by touching which the heating of the metal, the melting of the solder and the flux, the distribution of the solder over the metal surface are provided. For rapid heating and heat transfer to soldered metals, the tip material must have a high thermal conductivity, which causes the use of copper.
The shape and size of the soldering tip significantly affect the quality of the soldering. In size, the sting is conditionally subdivided into a standard one, having a diameter of 4–5 mm, and a miniature sting, with a diameter of 2–3 mm. A miniature sting is used when soldering thin wires and very small copper parts.
The shape of the sting can be made in the form of a scapula, cone, needle, or a special form for certain works. The most common sting is in the form of a blade with a 45º bevel on one side or with bevels on both sides (such as a screwdriver). In addition, the sting can be straight in length or angled for easy soldering.Back to table of contents
Schemes of temperature controls of the soldering tip.
In order to solder a soldering iron, it is necessary to carry out certain preparatory work. First you need to clean the surface of the metals, which will be applied to the solder. At the considerable sizes of details cleaning with an emery sandpaper is recommended. Cleaning from dirt, oils, fats produced by solvent. Steel surfaces are cleaned with soldering acid.
The preparation of a soldering iron tip is important. The working surface of the tip should be smooth, without any sagging, shells or other defects, and also have the shape provided by the structure. If the end of the tip has been deformed or partially melted, then you should return the desired shape using a file and form a 45º bevel.
For high-quality soldering, it is advisable to bite the working surface of the tip, i.e. cover with a thin layer of solder. To do this, heat the tip in a soldering iron, rub the work surface with rosin and dip it into the molten solder. Excessive mass of solder should be removed by quickly moving the rag over a hot surface or by rubbing the surface of the sting over the wood.
To conveniently carry out the soldering, you need to install the soldering iron in a position in which you can easily take it with your hand and use it for its intended purpose. During operation, the soldering iron may heat up above 300ºС; 220V is suitable for it - all this makes it necessary to optimize the place where the working soldering iron is placed. For these purposes serves as a stand for a soldering iron. It can be standard, purchased, but usually it is made independently. The self-made stand can have the form of a flat base on which two brackets are fastened, bent so that a saddle for installing a soldering iron is formed in the central part.Back to table of contents
Connection of single-wire aluminum wires by soldering double twist with chute: 1 - double twist; 2 - solder stick; 3 - propane-butane burner.
Soldering is carried out in a specific order. The soldering iron prepared for soldering is installed on the stand and is included in the network. Soldering begins when the tip of the soldering iron reaches the required temperature. Typically, the heating time of the soldering iron is 5-6 minutes. During this period, it is necessary to correctly determine that the temperature of the sting has reached the desired value. Properly heated soldering iron (temperature 230-290 ºС) causes rosin to boil and uniform solder melt. If the temperature on the sting is insufficient (underheating), then the rosin only softens and melts slightly, and the solder acquires a pasty consistency. Significant excess of heating leads to splashing and hissing of rosin, and the solder loses its elasticity of the melt. This soldering iron must be turned off and slightly cooled.
Directly the process of soldering begins with the tinning of surfaces that need to be soldered. For this, the tip of the heated soldering iron, after placing it in the rosin, is carried out on the metal surface for applying the flux. Then, using the tip, the molten solder is transferred and applied with a thin layer to the entire surface. To strip the wire, its end is pressed into the molten rosin, and then the melted solder is applied to it in a thin layer.
For soldering metals, trimmed surfaces are pressed tightly against each other. A hot soldering iron is brought to the place where the surfaces meet 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 solder is transferred to the soldering section. The pressing of the surfaces to each other is maintained until complete cooling and solidification of the solder.
Properly prepared wires for soldering LED strip.
When soldering wires to each other, their ends (previously trimmed) are recommended to tightly twist in advance between each other. This will ensure reliable contact when soldering. During the soldering process, the soldering iron is brought to the connection with the right hand, and the end of the solder wire is inserted into the soldering area with the left hand. The molten solder is distributed with a soldering iron over the surface of the twisted wires so that the space between the stranded wires is filled with solder.
If the wires can not be twisted, they are soldered with an overlap, i.e. their ends are laid parallel to each other with pressing. In this case, one of the wires is held by the left hand and pressed against the second wire. Soldering iron is transferred molten solder from the bath in the soldering zone. Solder should fill the space between the wires. The wire adheres by hand and after removing the soldering iron from the soldering zone, until the solder is completely set.
Butt-welding of wires is not performed, as it does not provide the necessary strength of the connection.
If it is necessary to solder the wire to the middle of another wire, then it is advisable to twist the end of it to the right place around the second wire. Soldering should be carried out in the same way as soldering twisted wires. In the case when there is no possibility of winding 2-3 turns, a partial coverage of the surface of the second wire, i.e. the wire is bent around the second wire by 180º. With such a soldering with one hand, the attached wire is held and it is securely pressed against the surface of the second wire, and the second hand handles the soldering iron.Back to table of contents
Features of other rations
Conductive soldering of printed circuit boards.
When soldering elements of the board, the legs of these parts are usually passed through holes in the board. The ends of the legs are soldered to the track on the board on the reverse side. The departure of the end of the leg parts is 1-2 mm. When soldering with one hand, the part adheres to the front side of the board, and the soldering iron tip with solder is brought from the reverse side. The molten solder should fill the entire hole space and spread out in the form of a small patch covering the end of the part's leg on the reverse side of the board. The time of exposure to a heated soldering iron - no more than 1-2 seconds.
When soldering small parts to a larger small part is pressed to a larger one with tweezers or thin pliers. This must be done in order not to burn your hands. Further operations are similar to soldering the wire.
In the case of soldering flat or rather large parts, one of them is pressed against the other with thin pliers. Initially, the soldering iron is heated in the soldering zone. For this purpose, the sting of the metal surface is carried out not with the tip, but with the entire beveled working surface of the sting. The soldering iron is held or slightly moved along the surface until the solder layer melts on the parts. After that, the soldering iron is transferred from the bath melted solder. This transfer of solder is repeated several times until the entire soldering zone is processed.Back to table of contents
If the question of how to learn how to solder is solved, then the following tool should be prepared:
- soldering iron;
- side cutters;
- emery sandpaper.
It is recommended to prepare additional materials - the lining for the soldering section (plywood, textolite), a bath for rosin and solder, and an insulating tape.
The question of how to learn how to solder with a soldering iron is solved very simply. You need to prepare everything you need and start training. It’s best to start with soldering wires. After several attempts, confidence and experience will come.