Almost everyone who learned to solder on their own, at first, had failures. Either to blanks and parts, or the soldered seam suddenly fell apart.
Without knowing the technology of soldering, it is difficult to guess why this happens. And the secret is simple - the parts were not prepared for soldering, and the solder did not “stick” to the surfaces. Soldering acid helps to cope with the problem, removing oxides and contributing to an excellent connection.
To prepare parts for soldering, it is necessary to clean them from particles of foreign materials - dust, sand, water. In addition, it is necessary to remove the oxide film from the surface, which is present on almost all metals.
And if the first condition is easy to deal with mechanically, with the help of a file, file, emery skin, then the second condition is difficult to fulfill without the use of chemical compounds - an oxide film appears very quickly on the metal surface.
Substances that remove the film and prevent the formation of a new one are called fluxes, and the most effective of them is soldering acid. It is an active flux, that is, when soldering, it chemically affects the composition of the metal surface.
Professionals never have a question - why soldering acid is needed, they know very well that very often it is impossible to complete the tasks without it.
Soldering acid is used for the following metals:
If copper or brass parts are successfully soldered with borax, then it is often possible to solder aluminum or steel blanks to each other only using soldering acid. Upon completion of the work, the active flux must be washed off with water with a small alkali content.
Acid is bought in stores, or made independently using chemicals. Although the acquisition source materials can be more expensive than a ready-to-use flux.
In the general case, zinc chloride is called soldering acid, but the composition of the substances used in practice is somewhat different. Most often, soldering is done using preparations based on hydrochloric or phosphoric acid with the addition of solvents.
Concentrated hydrochloric acid is not applicable because it corrodes the metal. For electronic circuits, acidic substances are not used, soldering with rosin or choosing another inactive flux.
One of the universal types of liquid flux can be considered soldering acid FCA, produced by the chemical industry.
The composition of this drug includes:
At home, soldering acid is made by dissolving zinc in hydrochloric acid. To get satisfactory results, you need to know how to solder metals and alloys with soldering acid, as well as strictly follow the safety rules when working.
For soldering, tin-lead solder (PLS) is commonly used. Its main component is always tin, and lead is added in proportions, depending on which the solder acquires the properties necessary for soldering.
Lead makes the material softer and more fluid, while tin provides strength to the hardened joint.
Despite the presence of lead, fluidity is often insufficient to overcome the forces of surface tension in the solder drop, and with a small amount of adhesion to the metal surface, the solder remains in the form of a drop that does not want to stick to the parts.
If the surfaces are preliminarily cleaned of oxides, then the adhesion force will exceed the surface tension forces and the solder will spread over the surface, providing good adhesion, that is, sticking.
To clean the surface, it is mechanically cleaned with a file or sandpaper and soldering acid is applied. It can be applied with a small brush natural materials or with a small spatula.
Often the composition is contained in plastic bottles with dispensers that are convenient to use. The flux must cover the entire surface to be soldered, otherwise the solder will not adhere well to it.
During contact of the heated solder with the surface, soldering acid evaporates, but its presence is no longer required. After the solder is applied, it itself performs a protective function, preventing oxidation. This process is called tinning.
Both soldered blanks are subject to tinning. After tinning, you can easily connect them by applying additional solder to the junction.
Of course, when soldering with a soldering iron, the tool must also be clean and the tip made of copper must not contain oxide films. To do this, the sting must first be irradiated by dipping it heated in soldering acid and applying solder to it.
Sometimes when soldering with soldering acid, you can do without a soldering iron. One of these methods is used, for example, when soldering twisted wires during electrical work on the electrical wiring.
In this case, the flux is applied to the twist with a brush, and for the best effect, the twist is dipped into a small container with acid. After that, the twist is immersed in a container with molten solder and held for about 1 minute so that the wires warm up well and the solder penetrates to all points on their surface. Such soldering provides excellent electrical conductivity when connecting wires.
After soldering, it is necessary to remove soldering acid residues from the joint in order to avoid corrosion of the metal and destruction of the joint in the future.
Please note that when installing printed circuit boards electronic circuits, when soldering electronic components of radio devices, it is not recommended to use soldering acid, as it can damage very thin conductive tracks of the boards. When flux is applied, soldering acid can dissolve them.
In the production of soldering acid, hydrochloric and phosphoric acid. They are very active (although phosphoric is weaker) and easily react with many chemicals. Contact with the skin, such substances cause a chemical burn.
Even when diluted, their vapors can damage the mucous membrane of the sense organs.
Given the above facts, the safety rules for handling soldering acid consist in the safe storage of the drug, the use of protective clothing and gloves, and good ventilation of the working area.
Subject to the soldering technology, they allow to obtain a high-quality and durable connection of difficult-to-solder materials.
The composition of fluxes created using acids can vary depending on their application. Different types of fluxes have their own characteristics, which should be taken into account when soldering certain metals.
If we talk about soldering acid in general, then it is a solution of acid in various substances. Acid in its pure form is practically not used for soldering, since, being an extremely aggressive chemical compound, it can have a destructive effect on various materials, including metals.
It is not recommended to use soldering acid when working with printed circuit boards, since thin connection bars and contacts of radio components are not able to withstand such aggressive impact. The best option for soldering radio circuits is or fluxes created on its basis.
Let's imagine the most common fluxes based on acids
Orthophosphoric acid is an inorganic chemical compound of medium strength. It is a colorless substance, however, light yellow stains can sometimes be observed in it. To obtain a flux, phosphoric acid can be diluted with water, ethanol, alcohol, and other solvents.
Due to its high aggressiveness, hydrochloric acid in its pure form is not used for soldering. In most cases, it is diluted with water in various proportions. Zinc can be added to the solution to improve the setting properties. This type of soldering acid is used to create solder joints from the most complex metals.
Sulfuric acid is a colorless and odorless oily substance. Sulfuric acid flux is made by diluting it in water or sulfuric anhydride in certain proportions.
Depending on the scope and technology of application, the ratio of acids and solvents in fluxes can be different - the acid content in them ranges from 25% to 85%.
Before making a choice in favor of one or another soldering acid, it is necessary to determine exactly what tasks are to be solved with its use. Based on this, it is necessary to choose a flux with the most suitable composition.
A solution with phosphoric acid is optimal for soldering metals affected by corrosion. This substance effectively fights oxides, which makes it possible to obtain a fairly high-quality compound.
Fluxes based on hydrochloric acid are considered universal, they can be used for soldering a wide range ferrous and non-ferrous metals, as well as alloys. For soldering large-scale parts, concentrated hydrochloric acid is used, since in such cases its aggressiveness is not critical for the safety of the metal.
In all cases, the choice of acid concentration in solutions must be correlated with the cross section or thickness of the parts to be soldered.
An important indicator of the quality of solutions is the presence of sediment in them. In fluxes, the presence of a minimum amount of undissolved substances is permissible, however, their abundance indicates a poor quality of the solution.
Instruction
The choice of acid depends on the type of metal or alloy. For soldering, including galvanized, the so-called soldering acid is used - a solution of zinc chlorate. For soldering, orthophosphoric acid and special multicomponent fluxes are used. Aluminum is not brazed at all, as there are no available fluxes to dissolve the aluminum oxide film. Acid is not suitable for printed circuit boards, as the occurrence of corrosion and short circuits between conductors.
If you decide to use a soldering iron, then it can be ready-made (it is sold in the form of a paste, but you can do it). Take about 100 ml of hydrochloric acid, put pieces of zinc there, taken, for example, from batteries. A chemical reaction will occur in which hydrogen will be released, so this work must be carried out in a ventilated area away from fire. When the hydrogen bubbles stop rising, the solution should be allowed to stand until transparent, and then carefully poured into a vial. Soldering acid.
Before soldering, clean the surfaces with a file or sandpaper to rid them of pollution.
Apply acid to the soldering site, this can be done with a brush, then use a heated soldering iron to cover the surface to be soldered with solder - tin or its alloy. If the solder does not want to lie flat on Right place, must be re-treated with acid.
Solder the surfaces carefully. When working with a heated soldering iron, remember the fire safety rules and do not litter the workplace with flammable objects.
After work, neutralize the acid with an alkali, such as a soda solution, and then rinse the solder joint to remove any acid residue. In rare cases, acetylsalicylic acid is also used as a flux.
Sources:
Soldering is an integral connection of metal products using a more fusible metal. Soldering technology may differ depending on the type of metals to be joined and on the conditions in which the product is to work. So, soldering printed circuit boards in electronics and repairing silver jewelry are performed in different ways.
You will need
Instruction
In electronics, when soldering parts containing silver, usually used, containing 60% tin and 40%, which melts already at 180 ° C. Prepare the solder used by the circuits. It comes in the form of thin tubes filled with resin that acts as a flux.
Clean the surfaces to be soldered by removing oxide films that have formed over time. Only in this case, the heated solder creates inner join With silver m.
In place, heat the part to a temperature above the melting point of the solder. Difficulty may arise when heating a large surface area with good thermal conductivity, since the power of the soldering iron may not be enough to heat it.
When soldering silver parts, protect the soldering area from exposure to atmospheric oxygen. To do this, it is enough to use a suitable flux (colophonium), which forms a protective film over the soldering point. When the solder is melted, the flux is evenly distributed over the surface of the liquid metal.
Solder jewelry made from, produce either high-temperature solders corresponding to the metal sample, or solders of a lower standard, but with a mandatory silver content. Solder silver products only in the most extreme cases and with unconditional agreement with the customer (the owner of the jewelry). This is done for the reason that the product may become difficult in the future: if it does not know that the product was previously soldered with tin and starts it with ordinary high-temperature solder, the product may simply burn out.
Sources:
Solder radio components in fees much easier than connecting free wires, because the holes in the boards perfectly fix the parts to be soldered. Although here the result of the work will depend on experience and a little luck. The very first circuit assembled on a breadboard is most likely not very successful. But you should not be upset - over time, the quality of the connections will only grow.
Instruction
Now you need to circle the soldering iron tip around the contact being processed in a semicircle, at the same time moving the solder in the opposite direction. In the same way, apply about 1 mm more solder to the soldering place. By this time, the place of soldering will be heated so much that, under the forces of surface tension, the melted solder will be evenly distributed over the entire contact area.
The last step is to quickly move the soldering iron tip away from the place to be soldered. At this time, while the hedgehog liquid solder, covered with a thin layer of flux, takes its final form, solidifying.
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If the tip of the soldering iron is heated to the optimum temperature, the whole process will hardly take more than 1 second. Hone your skills, practice soldering parts, and in the end your movements will become clear, and the connections will be of high quality and similar to each other.
The ability to solder is far from the last thing that every man should be able to do. These skills can be useful in everyday life when connecting wires and parts of electrical circuits or repairing a car radiator, and in production - during installation. copper pipes wires.
Copper is a metal that can be easily soldered. The surface of copper products is easy to clean from dirt and contaminants without the use of aggressive substances. A range of low-melting and available metals and alloys have excellent adhesion with copper (adhesion of surfaces). When soldering copper, expensive and complex fluxes are not required, because this metal weakly interacts with atmospheric oxygen when heated.
These properties of copper make it easy to solder in a variety of environments using a variety of solders and fluxes.
For soldering parts, electric soldering irons or soldering stations of various capacities are used: the greater the mass and volume of the part, the higher the power of the soldering iron should be. For training, it is better to use an inexpensive soldering iron with a power of 25-50 watts.
Solder is a low-melting metal for soldering. The most commonly used solder is tin. Tin in its pure form is a relatively expensive metal, it is used for tinning and soldering utensils for storage and cooking. Tin-lead solder is used for soldering wires and electrical circuits.
Flux is an auxiliary substance used to prevent oxidation of surfaces prepared for soldering. Without flux, solder will not stick to copper surfaces. The most commonly used flux is rosin.
For soldering you may need:
Stand for soldering iron;
- side cutters;
- pliers;
- tweezers;
- stationery knife;
- ;
- desoldering pump or copper braid.
1. Clean the soldering area to a shine and tin.
2. Dip the tip of the soldering iron into the rosin, after picking up a little solder on it. The rosin melts.
3. Firmly press the parts to be joined together.
4. Attach a soldering iron with solder at the end of the tip to the place of their connection.
5. Run the tip of the soldering iron over the part or wire. This must be done quickly so that the rosin on the sting does not burn out.
6. Place of soldering, rosin during melting covers the surface of the part, and the solder, spreading, will fill the gap between the parts.
7. Remove excess solder with a soldering iron, desoldering iron, or braid.
At correct execution all operations, the solder will evenly spread, harden and hold the parts together.
If the brazed parts move when the solder solidifies, the soldering will be fragile.
The ability to solder, especially to solder copper well, is not given immediately, it requires perseverance and some practice.
Sources:
Fishing is not only a great pastime, but also an exciting hobby and sport. Often there are cases when, in addition to losing the catch, the mormyshka also swims away. The average price of this fishing tackle is 20 - 500 rubles. But why spend money if you can make a mormyshka at home.
You will need
Instruction
“Bite” small pieces of solder with pliers or wire cutters, since such small pieces are more convenient when soldering mormyshkas to the body - the pieces stick better to the soldering iron and melt faster than if you take the solder with a soldering iron. whole piece.
Using wire cutters, cut out a blank from a tin that resembles a future mormyshka in shape. Mormyshka (and hence the blank for it) can be made in any size you need.
Make a hole in the resulting workpiece with a needle approximately in the middle.
Treat the blunt edge of the hook with soldering acid (flux) and irrigate it with a soldering iron prepared in advance.
Pinch the sharp edge of the hook with tweezers.
Put the workpiece on a match (previously weighted with small bolts and nuts) so that the edges obtained when making a hole (step 2) are inside. The matchbox should be placed at a slight slope so that the molten hot tin would flow more towards the thick end. mormyshki. That is, if the boxes lie straight, then the tin will be evenly distributed over the surface, and this is not necessary at all.
Process nichrome wire graphite grease (this is necessary so that our hole does not disappear during soldering) and insert it into the hole. Pierce the box with the same wire to secure the future mormyshka on it.
Press the hook with tweezers to the brass blank.
Remove the nichrome wire from our mormyshki with the help of pliers - a hole was formed in the mormyshka.
File the surface and sharp edges mormyshki. If the hole for the fishing line is small, then it can be enlarged with a gimlet.
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The ability to solder can be useful in the most different situations, ranging from the repair of electronic equipment and ending with the need to solder a leaky car radiator. Knowledge right technology allows soldering with a high degree of reliability.
You will need
Instruction
In the vast majority of cases, soldering is associated with the repair or assembly of electronic devices. In order not to damage the electronic components, choose the right soldering iron power, it should be from 25 to 60 watts. The smaller and more sensitive to overheating the elements, the weaker the soldering iron should be. For example, for the weakest device should be used. For soldering the leads of transformers and other massive elements, a more powerful one is suitable.
In order for the soldering to turn out to be of high quality, observe the following rules. First of all, prepare the place for soldering and the leads of the elements, they must be cleaned and tinned - that is, covered with a thin layer of solder. For soldering, you will need a flux, use rosin or its alcohol solution. In the latter case, it is convenient to use a bottle with a nail polish brush.
Before starting soldering, prepare the soldering iron tip. Its tip should be covered with an even layer of solder. If the sting is black, burnt out, carefully clean it with a needle file, then dip it in rosin and immediately tin it. Soldering with an unprepared soldering iron is difficult, it does not hold solder.
Make sure that the soldering is not "cold", that is, made by a poorly heated soldering iron. With such soldering, the solder is not liquid, but lumpy, the junction is not filled with it, but smeared over. The color of the connection soldered in this way is dull, gray. Such soldering is very unreliable and does not provide the desired contact.
If you are soldering a radio component into the board, then with the right technology, the solder should completely fit the part leg and capture the entire contact pad around it. The color of the solidified solder in this case is silvery, bright. This soldering is very reliable.
Assembling an electronic device on your own, get used to doing everything very neatly and beautifully. Beauty is the key to reliable operation of the product. If the device is sloppy somehow, the installation is very careless, the wires are completely random, you should not expect from such a product. By saving time on installation, you will later spend it much more searching for the reasons for the inoperability of the assembled device. Conversely, if everything is done neatly and beautifully, the device usually starts working without any adjustment.
Sometimes it becomes necessary to solder metal or steel parts. Rosin in this case is not suitable, you must use special shop fluxes for soldering metal elements. Alternatively, you can use a regular aspirin tablet. Work in a well ventilated area as the smoke from aspirin is very acrid (do not inhale it). Remember not to solder electronic components with aspirin.
You can also use hydrochloric acid with a piece of zinc thrown into it as a flux for soldering iron. You can use zinc from an old battery case. A small bottle of about 50 ml will require a third of the battery case - just cut the zinc plate with scissors, put the trimmings in the bottle and leave for about a day. Apply the flux to the place of soldering with a brush.
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Not only workers in production have to work with metals, but also ordinary people at home or in their own workshops. Craftsmen, making a variety of things - from jewelry to technical devices - often use soldering, connecting wires and metal parts, and often they are faced with the need to solder brass parts.
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Instruction
Tin soldering, which is familiar to everyone, is not for brass - it leaves a noticeable mark, and also has a weak strength. When soldering brass, it is worth using a different, more reliable way. In order to solder brass parts, you will need a gas burner, as well as a graphite crucible, copper, borax and an asbestos base.
Solder for brass is made from one part copper and two parts silver, mixing and fusing them together on a gas burner in a graphite crucible. Lower the crucible into cold water and remove the melted and hardened solder. Flatten it and cut or sharpen shavings from the solder using a large file.
Brass parts, you want to solder, put on an asbestos base and moisten with flux from boric acid and storms. Then sprinkle the joint of the parts with pieces of solder that you sharpened in advance, and then begin to gently heat the joint with a gas burner.
Gradually bring the heating temperature to seven hundred degrees. Monitor the temperature of the burner - do not overheat brass so as not to spoil the details. If you are soldering large and massive parts, heat them gradually; if the parts are small and thin, remember that they heat up very much. This method is more complex than conventional soldering with tin, but it is characterized by increased strength and connection with brass parts.
The soldering of metals has become widespread in electronics, radio engineering and in tool business. When soldering parts, in most cases lead-tin solders are used. But they are suitable mainly for joining copper parts. If you want to create a permanent connection steel products, you will first need to prepare a special refractory solder.
Most often for soldering printed circuit boards in radio products and household appliances they prefer to use ordinary pine resin rosin, but it can be replaced with other components. In molten form, it contributes to the spreading of tin solder along the copper tracks of the board. This allows you to securely solder the legs of the radio components and the ends of the connecting wires. Rosin allows you to effectively solder copper, tin and silver products. In order to solder galvanized, stainless iron, radiators, buckets, pans, various alloys, brass and other metals, acid solutions can be used.
Vial with acid solution for soldering metals
It is important to choose the right acid solution. It depends on the type of metal from which the parts are made. It can be an aluminum or copper radiator, a kettle to be soldered, copper, brass or roofing iron:
To do this, it is enough to throw pieces of zinc into 100 ml of hydrochloric acid, which can be removed from the case of finger batteries. After the end of the chemical reaction, zinc will dissolve, releasing a large amount of hydrogen.
It will be correct to carry out the process in a well-ventilated area, in the absence of an open flame.
After the solution has cooled and settled, the upper transparent yellow part is poured into a clean glass dish. The sediment is poured into the ground, into the sewer with metal pipes Not recommended. Acid can damage pipes and seals. The rest of the solution is ready for processing galvanized iron roofing.
How to solder sheets of roofing iron
Orthophosphoric acid is used for soldering as a flux and for cleaning metal from rust.
The solution is transparent light yellow or colorless, when heated to 213ºС, it is converted into H 4 P 2 O 7 (pyrophosphoric acid), which degreases the surface of metals. The composition dissolves the oxide film on various metals and alloys:
To solder metal products (pipes, radiator, buckets, pans), the surface of the elements is carefully cleaned, you can use a file or sandpaper. An acid solution is applied to the cleaned areas with a brush, after which the solder is melted on the surface with a soldering iron to a liquid state.
Liquid solder serves the cleaned places, when boiling, the acid flux comes to the surface. When the solder hardens, the elements to be soldered are securely and hermetically fixed.
You can solder with a powerful soldering iron or open fire from a gas burner. Various heat sources can be used depending on the surface area to be heated and the melting point of the solder.
The remains of the acid flux are washed off with water, preferably with a soapy, alkaline solution, this will prevent further corrosion of the metal.
Machined and brazed stainless steel elements
Acid can damage the skin and muscle tissue, while inhaling vapors affects the respiratory organs. In contact with air, hydrochloric acid enters into a chemical reaction, smoke is visible above the open container. It is possible to work correctly in these conditions in goggles, rubber gloves, a gas mask, and in a respirator.
If the solution gets on the skin, wash this part of the body with a 6% alkaline solution or simple soap. It is not recommended to solder radio boards with acidic fluxes. Acidic components are difficult to wash off from them and contribute to the decay of copper tracks. It is better to replace them, there is a special paste for this.
It will be correct to store solutions with acid for soldering in containers made of the following materials:
Such dishes do not react with acid; in it, the prepared composition can be stored for a long time.
In domestic conditions, in the absence of a soldering iron, copper wires with a diameter of up to 2 mm can be soldered. For soldering radiators, dishes, special solder, blowtorches, gas burners are used, since the copper of the soldering iron rod is not able to heat up a large surface area. There are several ways:
Tinned and brazed copper wire
Heating solder with a blowtorch (torch)
The mixture melts and carefully envelops all the junctions of the wires. After solidification, the aluminum gutter is removed, the junction is isolated.
Solder chips can be sharpened with a coarse-grained file.
Soldering paste is sold in radio parts stores, but you can cook it yourself. 12 ml of ordinary water is added to 32 ml of hydrochloric acid, then pieces of zinc - 8.1 g. For this, enameled dishes are used.
After the end of the dissolution reaction, tin is added to the composition - 8.7 g. When the second dissolution reaction is over, the water is evaporated to a pasty consistency of the solution. The paste is transferred to a porcelain container, where the powder is poured, which includes:
This paste is kneaded with 10 ml of glycerin, heated and mixed.
How to solder correctly, the sequence of actions:
The paste is very effective when it is necessary to solder copper wire, small parts made of alloys based on copper, brass, such as radiators, samovars and other products.
Buckets and pots with holes no more than 5-7 mm in diameter are recommended to be soldered without using a soldering iron with POS-60 solder. Holes on dishes can be safely soldered. To do this, the holes are carefully cleaned with sandpaper from the inside of the container. The hole along the edges is given a conical shape, the cleaned places are treated with a brush with a solution of soldering acid.
In order to prevent solder leakage from outer side, the entire bottom or individual places where it is required to solder the holes are covered with thin tin plates. WITH inside powdered solder with rosin is poured into the cleaned holes. Places of soldering are heated over an open fire until the solder melts and fills all the cracks with it.
For radiators, stripping and soldering are carried out from the outside. To prevent the flow of solder inside, the hole is closed with a plate of tin, galvanized iron, which can be replaced with copper or brass. The choice depends on the material from which the radiator is made. Homogeneous metals and alloys that are similar in composition are easier to solder.
After the end of the process of soldering radiators, the internal and outer surface thoroughly washed with an alkaline, soapy solution in order to exclude the effect of acidic components on the metal.
Flux bottle for aluminum soldering
When it is necessary to solder aluminum parts, special solders are used:
The surface treatment sequence is the same as for the preparation of iron utensils. In order to qualitatively solder aluminum, rosin is added to the powder, but the melting point must be above 500ºС. It is recommended to stir the solder in the hole, you can use a thin copper tip of a soldering iron.
The composition is not much different from the paste that is used to solder without a soldering iron, the following components are included in the powder:
For a pasty consistency, add diethyl ether - 10 ml, it can be replaced, use glycerin - 14 ml.
Soldering sequence:
You can learn how to solder correctly by watching this video.
From the above information, it follows that, if desired, and the presence of certain materials in domestic conditions, it is possible to solder in various ways, achieving high-quality fastening of parts and tightness of containers.
Soldering copper pipes with a torch
You can solder with or without a soldering iron almost all metals, alloys, aluminum, brass, copper, wires electrical circuits for various purposes, metal utensils, radiator cases and other items of equipment.
Experienced craftsmen - electronics engineers and home radio amateurs know that for a quality connection, you will need not only a soldering iron, but also additional accessories. For soldering, flux and solder are used, the latter is made on the basis of lead and tin, often offered in the form of wire. Characteristics of the ratio of wire, flux may differ in parameters depending on the type of product.
Flux acts as the second component, a common form is used in the form of rosin. It helps to qualitatively, quickly solder parts of the copper composition, wires and other materials. Soldering acid can work with brass, nickel, stainless steel, etc. materials.
The category to which soldering acid falls differs from other reagents, has a number of positive properties. As a flux, the product is distributed only in liquid form, some compositions can be diluted to reduce the concentration when interacting with the metal. Before using the element, it is worth understanding what soldering acid is for.
Before soldering metals, it is necessary to prepare the areas for application. With prolonged use, metals tend to oxidize, a layer of dirt and dust falls on them. If dirt can be dealt with mechanically, with the help of a skin or a file, then the oxides are eliminated only with the use of chemical solutions. Soldering acid helps to prevent the appearance of a new film, remove deposits present.
Base metals that can be treated with soldering acid:
Brass, copper alloys can be soldered with borax. Aluminum or steel products will not connect without soldering acid. Before soldering with acid, the part is processed from solid deposits, after soldering it is washed off with water with a low alkaline content. Varieties of soldering products are produced according to GOST 23178-78 standards, they have fluidity, low viscosity.
Soldering acid is divided into two main types, regardless of the scope, orthophosphoric and hydrochloric type. Regardless of the composition, the purpose is to remove oxides and contaminants from the soldering areas. A high-quality, neat seam can only be performed if the conditions for the preparation of metals are observed. The durability of materials increases due to the formation protective film from oxidation on the joint surface.
It is important to know that the use of flux when working with electronic boards is strictly prohibited. Thin and fragile elements can be rubbed off the board structure, soldering acid produces conductive connections. All these factors can have a deplorable effect on the performance of the unit, the design of the general condition.
A solution of zinc chloride is used for soldering iron compounds. The composition is zinc dissolved in hydrochloric acid. The solution is produced as follows:
Proportional parts are taken as an example of 1 liter of brine per 400 grams of granulated zinc. At the end of the work, the surface should be treated to stop the reaction; a soap solution is excellent for this. Before making your own, remember that it is important to follow the sequence. The acid is diluted with zinc, and gases are formed, it turns out enough explosive mixture. All actions are performed in a ventilated place.
for soldering aluminum alloys olein is great. Not applicable clean view, available only in technical condition. A stable state is achieved by mixing olein with various fatty acids. Then lithium iodide reacts, which completes the mixing of the mass for soldering aluminum.
Soldering with oleic acid allows the joining of materials from copper and aluminum alloys, without the formation of a chemical film and oxidation.
The flux is used to protect against corrosion processes at the joint, when mechanical action, a new film is formed, which allows you not to worry about the reliability of the connection.
Instead of soldering acid, other fluxes do not have similar properties, it is possible to use machine oil with crushed sawdust, the soldering process occurs when the composition is rubbed during docking. When heated, the oleic type of soldering acid evaporates, but the soldering place is tinned, it is pointless to worry about a quality connection.
When metals are treated with an orthophosphoric solution, a protective film is formed that prevents the formation of oxides, chemical reactions metal. The characteristics of the solution consist in a colorless substance, of an inorganic kind. The hygroscopic structure in the form of a paste-like structure interacts when heated and dissolves in liquid composition. It has good flow properties and can be easily cleaned with water after work.
Orthophosphoric acid is used for soldering carbon and alloy steels. Copper and nickel alloys are also suitable for work, the operating temperature during soldering starts from 350 degrees. The acid film is loosened and removed to the surface by dissolving the oxide layer. Reliable soldering is achieved by forming an oxide film with phosphoric acid.
The salicylic base, common in the composition of aspirin, is used as an ingredient. Most widely used with precious metals, due to weak interaction with product particles.
The main advantage is the protection against oxidation of the soldering point, it is not necessary to remove the flux, unless there are additional requirements.
Versatility of application, cheap production allow the use of soldering acid based on salicylic compounds. Caustic emissions suggest a working exhaust when performing soldering operations, and the negative side is poor interaction with aluminum.
It is possible to use improvised means, it is enough to grind an aspirin tablet or another preparation containing salicylic acid. The powder is applied to the place of soldering; when working with wires, soldering can be done directly on the tablet. A more convenient mixture is made together with petroleum jelly, in proportions of 1 to 2, the paste is easy to apply to the place of soldering with a swab, and removed at the end of work.
Each composition has certain advantages, soldering accessories are no exception.
Main positive aspects:
In addition to the positive aspects, there are some disadvantages that can limit the use of a chemical element:
Orthophosphoric acid has the formula H3PO4, which consists of phosphorus itself and diethylamide. The proportions can be different from the required concentration, in most cases a ratio of 1 to 4 is used. There is a variety of acid with zinc impurities in ratios of 1 to 2 parts of the solution.
The main properties of the material imply aggressiveness. Active interaction occurs with any material, this fact requires a careful attitude to the compounds. During work, special rules must be followed, because. may be positive or negative. The liquid form allows the composition to penetrate into hard-to-reach places, to achieve high soldering strength. The main types of soldering acid are solutions, since 100% concentration will not allow you to work with most metals.
The composition of the soldering acid is selected in accordance with the working surface of the material. The main criterion should be the quality of the solution, because incorrect concentration, you can always lower it at home. It is not permissible to use compositions with the presence of sediment or turbidity of the container.
It is important to remember that liquid fluxes are one of the few soldering accessories that have an expiration date that must be considered before use.
A difficult choice always haunts when buying. The compositions are different, there are a large number of manufacturers on the market. It is necessary to determine what type of work will be carried out; for this, the purpose of the soldering acid composition is being studied. Orthophosphorus compounds are the most common, they fight oxides well and are not so aggressive. Salt is more versatile, because. applied to many metals. Sulfur is the most active option, used when soldering thick products.
With some knowledge and improvised materials, it is possible to make soldering acid at home. The set of ingredients is not large, they can be purchased at the hardware store:
Soldering acid is made by hand in a certain sequence. It is necessary to fill the container with pieces of zinc, then fill it with saline. Actions are performed in a well-ventilated area, if the solution gets on the skin, it must be immediately rinsed with running water. After manufacturing, the mass is poured into an airtight container for proper storage.
Aggressive properties require a special approach to safety. Storage is carried out in original packaging, protected from direct sunlight.
It is better to work with good ventilation, using necessary funds protection.
The skin reacts negatively to aggressive substances. At hit on hands, it is necessary to wash out immediately with water, laundry soap. Inhalation may cause irritation oral cavity, and in case of contact with eyes, seek medical attention.
For a quality connection, it is important to follow certain instructions, the work is different from soldering with ordinary solder.
Soldering acid is used in many cases, it is important to follow the steps before work:
After the end of the process, it is necessary to remove the remaining solution. You can do this with ordinary soapy water or a solution of soda.
