Soldering borax how to use

How to solder metal using borax - Welding Pros

Borax is a flux used to join metal parts by soldering.

Borax, which is produced in powder form, belongs to the category of high-temperature fluxes, since its melting point is in the range of 700–900°.

Borax powder, the characteristics of which are specified in the relevant regulatory document (GOST 8429-77), dissolves well in water and, when heated, turns into a glass mass, which provides protection for the soldering zone.

Borax crystals can be transparent or grayish, but always have a characteristic “bold” shine.

Areas of application

Borax, which is a salt containing a weak boric acid and a strong base, also has a scientific name - sodium tetraborate decahydrate.

This substance, used as a flux, is used to solder metals such as steel, cast iron, copper and its alloys.

In this case, for such soldering, medium-melting solders are used, the basis of which can be copper, brass, silver and gold.

When borax melts, which occurs at a sufficiently high temperature, the surfaces of the parts to be joined are cleaned, and the oxides that are present on them dissolve in the heated flux.

During the soldering process, for which a refractory flux such as borax is used, which meets the requirements of GOST 8429-77, salts are formed that crystallize on the surface of the joint being formed.

After completion of the technological operation, salt deposits must be removed.

GOST requirements for the composition of borax-based flux

To obtain boron flux from borax, which can be used when soldering parts made of copper, cast iron, steel and other metals, this substance must be mixed with boric acid in a 1:1 ratio.

The resulting mixture is thoroughly ground in a porcelain container, and then the excess liquid is evaporated to obtain a dry residue, to which fluoride and chloride salts are added.

Using this technology, active fluxes are obtained that allow high-quality soldering of parts made of various metals.

GOST 8429-77 Borax.
Specifications Download

Benefits of use

Copper pipes as components of pipelines for various purposes are very popular today.

In this regard, brazing copper, which uses a flux such as borax, has become a fairly common technological process.

The use of this method of connecting copper products allows not only the installation of new pipelines, but also high-quality repairs of those that have already been in use for a certain time.

Borax removes the oxide film from the surface and promotes the spreading of liquid solder

The use of technical borax as a flux when soldering copper has the following advantages.

• Metal parts in any combination can be subjected to high-quality soldering.
• Metal products that need to be joined by soldering can have any initial temperature.
• When using borax, high-quality and reliable connections can be obtained even between metal and non-metallic parts.
• Soldered joints made using this flux can be unsoldered at any time if the need arises.
• When soldering, the base metal does not melt, as happens during welding, which avoids such an undesirable process as warping (and, accordingly, changes in the geometric shape of the products being joined).
• The use of borax allows for excellent adhesion of the solder and the surfaces of the parts to be joined.
• Technical borax, used as a flux, provides high productivity for a process such as capillary soldering.
• The solder joints obtained using this type of flux are characterized by high strength, reliability and durability.

Brazed copper pipes using borax as flux

To understand what factors influence the quality of soldering, you should know the stages of this technological process. The soldering algorithm is as follows.

• The surfaces of parts that need to be connected by soldering must be carefully prepared.
• Contaminants are removed using standard means - brushes, rags, etc. And to remove refractory oxide films from the surface of parts, a flux such as technical borax is used.
• The surfaces of the products to be joined must be heated to a certain temperature, for which a blowtorch is used.
• Liquid solder is introduced into the gap between the parts to be joined, which is also heated using a blowtorch or a regular gas torch.
• The interaction of the heated base metal and liquid solder ensures a reliable solder joint.
• The soldering process can be considered complete at the moment when complete crystallization of the solder occurs.

How to solder copper pipes

Before you start soldering, you need to prepare the following tools and consumables:

• brushes with metal bristles for cleaning joined surfaces;
• devices and tools with which the parts to be joined will be cut to the required sizes;
• gas burner or blowtorch;
• solder, which is selected depending on what material the parts being connected are made of;
• borax, the characteristics of which must meet the requirements of GOST 8429-77;
• brushes necessary for applying flux.
• Flux, solder and torch are the main components for soldering copper alloys

Particular attention should be paid to the choice of gas burners, which are presented in a large assortment on the modern market.

Such a device, designed to ensure complete heating of the base metal and solder, can be equipped with automatic piezo ignition or manufactured in a classic design.

You should only choose burners that use a piezoelectric element for ignition if such a device is manufactured under a well-known brand. Otherwise, it is better to purchase a regular high-quality burner that will provide you with uninterrupted operation for a long time.

Cleaning the joint before soldering

The soldering process itself using borax, including preparatory procedures before its implementation, is most conveniently considered using the example of connecting two pipes made of copper. This process is performed in the following sequence.

1. The internal surfaces of the connected pipes are thoroughly cleaned, for which a jaw with metal bristles is used.
2. External cleaning of copper pipes, carried out until their surfaces have a metallic shine, is carried out using emery cloth.
3. After thorough cleaning, borax is applied to the internal and external surfaces using a special brush.
4. Copper pipes coated with flux at the future connection must be joined together. After this you can start soldering.
5. Before starting the process, the pipe surfaces must be heated to the required temperature, for which a gas burner is used. The surfaces of the products to be joined should be exposed to flame for at least 15–20 seconds.
6. After the surfaces of the pipes are heated to the required temperature, solder is introduced into the soldering area, which also melts under the influence of the flame of a gas burner. Molten solder should be applied evenly to the surfaces of the parts to be joined to ensure the quality and reliability of the joint being formed.

Applying flux to the soldering area

After soldering using borax, the resulting connection should be inspected, for which destructive and non-destructive methods can be used.

Most often, such control is performed when inspecting the resulting connection for the presence of external defects.

A magnifying glass can be used to perform this inspection, which reveals many joint imperfections.

Application in forging

Borax is also used as a flux when carrying out such technological operations as forging.

When forging is performed, which is accompanied by significant heating of the workpiece being processed, a thick layer of scale forms on the surface of the workpiece.

There are also frequent cases when the workpiece is simply burned out, which leads to a significant deterioration in its characteristics. To avoid this, the surface of the workpiece during the forging process is sprinkled with a thin layer of borax, which acts as a flux.

Source: https://fgpip.ru/instrumenty/kak-s-pomoshhyu-bury-payayut-metall.html

How to use flux for soldering drills

Borax is a powder that is added to so-called high-temperature flux mixtures for soldering metal products. The melting point of borax is quite high - 700 - 900°C.

Soldering borax is very convenient in technical use, all its properties are well known, convenient and described in a special regulatory document - GOST 8429-77.

Where and how is borax used?

From a chemical point of view, borax is a sodium salt with the complex name “sodium tetraborate decahydrate”. With its participation as an active element in the protective flux mixture, a wide variety of metals are combined, up to complex and capricious alloys, for example, copper.

Tools and consumables for soldering.

At a high temperature, the borax begins to melt, as a result of which the surfaces to be welded are cleaned with the simultaneous dissolution of oxides in the hot flux mixture.

The essence of this process is the formation of salts followed by surface crystallization. This crystalline deposit is easily removed after the welding process.

How is flux with borax prepared?

The boron flux mixture for use in working with metals has its own characteristics and is prepared as follows: for example, borax for soldering brass is mixed with boric acid in equal proportions.

The mixture should be thoroughly ground in a special chemical vessel, and then all the liquid should be evaporated to form a final dry residue. Then fluorine and chlorine salts are added to the resulting substance. As a result, an active flux is formed, which will be an excellent assistant in heating metal parts of various types.

Advantages of using borax in working with metals

These advantages are especially evident in the processes of soldering brown copper pipes, which are often important components of modern pipelines. Such technologies are now in great fashion.

They are used both for connecting new pipes and for high-quality repairs of old pipelines that have been in use for a long time.

The most important role of borax in the flux composition is to remove the oxide film from the metal surface and activate the spreading of liquid solder over the surface of parts.

Technical requirements for fluxes.

Here are its technical advantages:

• Metal parts in any, even the most “inconvenient” combination can be merged.
• The connections are strong and reliable even between metals and non-metallic materials.
• Work can begin with metals having any initial temperature.
• Using this technology, parts can not only be connected, but also effectively separated - they can be unsoldered without any problems.
• The difference between soldering and classical welding is that the base metal does not melt, and therefore there is no phenomenon called “warping”. As a result, the parts are not deformed in any way.
• Borax helps in effective adhesion of solder to metal surfaces.
• Technical drill is indispensable for the method called “capillary soldering”: it affects its performance.
• Soldered joints are characterized by high quality and durability.

Stages of soldering with borax

The whole process consists of successive steps, the implementation of which is mandatory:

• Careful preparation of workpiece surfaces before heating.
• Cleaning is carried out to get rid of oxide films, this is where technical drill is needed.
• A blowtorch heats the surfaces to be welded to the desired temperature.
• Heated metal solder in a liquid state is introduced into the space between the parts.
• The essence of the connection is the combination of the base metal with liquid metal solder in a well-heated state.
• The process ends with the final crystallization of the solder.

Soldering copper pipes using borax

First you need to stock up on the necessary tools and materials:

• blowtorch or gas torch;
• special solder, selected taking into account the nature of the metals that need to be soldered;
• borax with optimal properties according to GOST 8429-77;
• metal brushes for cleaning parts;
• metal cutting tool;
• brushes for coating parts with a flux layer.

The choice of gas burner deserves a special warning. The fact is that these devices are offered on the market in huge quantities and in different models.

A fashionable device in gas burners is an automatic piezo ignition system.

And now the main stages of the soldering process using borax to connect two copper pipes:

1. Thorough cleaning of the surfaces inside the pipes with special brushes with metal bristles.
2. Now clean the outer surfaces of the pipes using sandpaper.
3. Applying technical borax using a brush.
4. Joining pipes that are coated with a flux layer to each other.
5. Heating the parts with a gas burner. The flame action must last for at least 20 seconds.
6. Solder is introduced onto the working area, which is also melted under the action of the burner. Solder is applied as evenly as possible.

Quality control of connections using borax flux is carried out using different methods: destructive and non-destructive. Most often, an external examination is sufficient to determine possible defects. You can even do this with a magnifying glass.

Source: https://respect-kovka.com/flyus-dlya-payki-bura-kak-primenyat/

Soldering borax

There are many types of solder that can be used in the soldering process. Each variety has its own characteristics and is used in a specific area. One common flux is borax, which is found when soldering complex metals such as cast iron or copper.

This type of consumable is used not only in large-scale production, but also for connecting various parts at home. It can be purchased at any store at an affordable price. It is suitable for various types of soldering. Borax contains several components, which simplifies the soldering process.

It not only reliably holds parts together, but also serves to clean working surfaces from oxide deposits and films. This flux melts at high temperatures, which is 800°C. To obtain a softer and more flexible material, it should be dissolved in water. The melting temperature will depend on this.

Thanks to the latest developments and technologies, the soldering drill can be used in various fields. These data, as well as the method for producing flux, are described in detail in the regulatory documentation.

Advantages

The advantages of soldering borax are:

• This flux is suitable for soldering various metals;
• wide availability;
• low cost compared to other materials;
• good solubility in water, thanks to which the necessary consistency can be formed;
• long shelf life.

Negative sides

Among the shortcomings, experts identify the following:

• after soldering is completed, a coating is observed on the surface, which should be removed;
• borax should be stored in a place protected from moisture, otherwise the flux will begin to deteriorate;
• Before starting soldering, it is necessary to correctly calculate the amount of flux.

Main types

Soldering borax is available in solid and liquid form. This is the main difference between them. The first type comes in the form of a powder with white solid particles. You can select enough of them to cover the entire surface of the metal, without the granules spreading. The flux is transported in a special sealed package that prevents moisture from entering.

Diluted borax is used for lighter metals and their compounds. In terms of its chemical composition, it is no different from the previous type, only dissolved in water. This feature allows soldering to be performed at low temperatures.

As a rule, it is used when working with small parts, for example, in the jewelry industry, since they can be placed in a container of soluble flux before soldering, which is very convenient. Flux gives the same effect in any state of aggregation.

The only difference is the technology of its use.

In the industrial sector, another type is often used - a mixture that, in addition to borax, also contains other fluxes. It is used if it is not possible to achieve the desired result with one substance. Mixing is carried out with the addition of boric acid.

Composition of borax and its chemical properties

Soldering borax consists of two components: BaCl and NaCl. Sometimes boric acid is added to it. Flux is not always used in its pure form, as it has a high melting point. It retains its chemical properties regardless of concentration, so it quickly dissolves oxides and other deposits formed on the metal surface. Borax also removes other substances and contaminants that interfere with normal soldering.

Main characteristics

Soldering borax is produced in two grades: A and B. Their characteristics and composition are standardized by special documents. The first grade is used for soldering non-ferrous metals, facade, etc. The second type is used for soldering wires, plumbing equipment, glazes, etc.

The only common feature is the state of the drill - fine powder. The percentage of flux, arsenic, sulfate, carbonate and other metals differs from each other.

Soldering technology

When working with this type of flux, you should adhere to a certain temperature regime, which is 400°C. In the manufacturing sector, flux mixed with boric acid is often found. This material is universal, as it is possible to work at lower temperatures.

Note! The ignited borax becomes transparent in color, similar to pieces of glass. .

Upon completion of soldering, a white coating forms on the surface of the structure, which should be removed. This is done mechanically. When mixing flux with another substance, maintain a 1:1 ratio. If the components are in a solid state, they are crushed in a special container.

 Important! The container and grinding tool must be made of non-absorbent material.

If the borax is in a liquid state, then it must be heated before soldering. At a temperature of 100°C, the liquid evaporates, forming a white solid residue. To increase the activity of the flux, BaCl or NaCl is added to it.

Manufacturers

Soldering borax is an affordable material and can be purchased at any store. There are many manufacturers on the modern market. Many experts recommend using flux from ChemPek and Khiamen companies. It is supplied in sealed packages that do not allow moisture to penetrate, so the material retains its properties.

Source: https://svarkagid.com/bura-dlja-pajki/

Soldering drill how to use - Metalworker's Handbook

Sodium tetraborate, which has its scientific name, is colloquially called borax. In Asian countries it is called "tinkal". It is familiar to representatives of many professions: soap makers, cosmetologists, doctors. People of different professions sometimes simply cannot do without this substance.

As a food additive, it is allowed only in third world countries, and in Russia and European countries it has long been prohibited for use. This is due to the fact that borax is not excreted from the human body, but, accumulating in tissues, turns into a toxic substance. As a food preservative, it has the number E-285.

• Description of the substance
• Area of ​​application of borax

Its melting point is 60 degrees. At 320 degrees, all moisture evaporates from the crystals and a white powder is obtained. Borax crystals are transparent or have a grayish tint, but always with a greasy sheen.

Description of the substance

Borax is a combination of boric acid and soda. This substance owes its appearance to the French scientist Enouville. Chemists derived its formula and identified three states:

• Pentahydrate.
• Anhydrous state.
• Decahydrate.

This substance is insoluble in alcohols, but dissolves perfectly in glycerin and hot water. Borax can be found in nature in the form of salt deposits when water bodies dry up.

The main deposits of this substance are located in Nevada and California, in Kashmir and the mountains of Tibet.

Area of ​​application of borax

This substance has found a wide range of applications and is actively used in various industries:

• In industry. In welding production it is used as a component of flux. It is also used for the production of glaze, glass and enamel. In mechanical engineering, this substance is used for the production of antifreeze, lubricants and brake fluids. For disinsection (insect control) at home, it is used as a toxic substance.
• In the textile industry. Treat the surface of the fabric before dyeing.
• In jewelry production. It is used as a flux for soldering metals. It is used to clean the surface of the metal so that the connection is strong. It is used when working with brass, silver and gold.
• In medicine. In this area, this substance is used to combat fungi. For this purpose, preparations from borax in glycerin are prescribed. It is considered a high-quality antiseptic, not inferior in its characteristics to copper sulfate and tannin. It can also be found in pharmacies as a solution of boric acid.
• In cosmetology. This substance is included in almost all cosmetic products. This is explained by its ability to soften hard water and serve as a preservative that extends the shelf life of masks, creams, shower gels, shampoos, etc.
• In soap making. This substance is found in bath bombs. This product owes its effervescent effect to the borax contained in it.

Use of borax in everyday life

This substance is actively used not only in production, but also in everyday life, in some cases it turns out to be irreplaceable. It is used as:

• All-purpose detergent. To do this, take two teaspoons of borax and dissolve them in two glasses of water. Store the substance in a closed container and add small amounts to water when cleaning furniture, washing floors, and windows.
• Insect and rodent control products. Many people know the good old method, passed down from generation to generation, with balls of potato or egg yolk and boric acid. For domestic insects, such a ball serves as real poison. With this method, it is important that insects do not have access to water, otherwise all efforts will be in vain. To control rodents, the powder is scattered along the baseboard on the floor.
• Mold control products. Due to excess moisture and evaporation, mold often appears in the bathroom. This substance will come to the rescue here too. This product can only be used on surfaces without paint, otherwise it will simply peel off. Borax is mixed with water to form a thick, paste-like consistency. Simply apply the mixture in a thick layer to the mold and leave overnight. In the morning, the mixture is removed from the surface, leaving the walls clean.
• Products to combat rust and limescale. Sometimes even expensive products cannot cope with limescale on the sink or toilet. This substance will help in this case too. For this purpose, it is recommended to pour a glass of borax into the toilet bowl and clean the earthenware with a brush in the morning. All stubborn stains will disappear without leaving a trace.

  Soldering plastic pipes instructions table

You can buy borax at a pharmacy under the name “Boric acid solution” . The powder can be purchased at a hardware store or searched online on specialized sites.

A kilogram of borax for technical purposes will cost about 150-200 rubles. In large quantities it can be purchased in packs of 25 kg. The pharmacy chain sells an aqueous solution. Its cost can vary from 14 to 100 rubles, depending on the region of residence. It is bottled in bottles with a capacity of 30 to 100 milliliters.

Source: https://ssk2121.com/bura-dlya-payki-kak-polzovatsya/

Advantages of soldering borax

• Copper borax is one of the few widely available fluxes for refractory metals;
• The cost of the material is relatively low in comparison with other materials of this kind;
• It is possible to dilute borax to the desired consistency in water, since it has good solubility;
• Flux is available in almost all stores and there are no problems finding a suitable brand;
• Long shelf life.

Flaws

• After use, a deposit of salts forms, which must be removed mechanically;
• It is necessary to choose storage areas that are free of moisture, since high humidity will cause the flux to deteriorate;
• To prepare the material for use, you need to spend time and choose the right proportion, which can lead to errors.

Varieties of Borax

There are two main varieties that relate to the appearance of the material. The first option is the solid form. Borax soldering flux is supplied in the form of a powder with fine solid fractions.

Thanks to this, it is easy to lay it on the metal surface before soldering in the required quantity and it will not spread at the same time.

This variety is supplied in a special box that protects the material hermetically from the penetration of moisture and other foreign factors. Fractions are white.

Soldering borax in powder form

The second type, which is more often used for lighter metals and their alloys, is diluted borax. In this case, you are offered the same material, but dissolved in liquid. Due to this, it can be used at lower soldering temperatures.

Using this type is also easier, since small parts are simply dipped into the liquid, after which they can be soldered. This is used both in the jewelry industry and in other places where small items are worked. Contacts, wires and other types of equipment come into good contact with dissolved flux.

Despite the fact that the principle of using borax for soldering in liquid form is somewhat different from the standard one, they have almost the same effect.

Source: https://svarkaipayka.ru/material/flyus-dlya-payki/bura-dlya-payki.html

Drill flux for soldering: what it is, where it is used, technical characteristics, pros and cons

Soldering borax is a high-temperature flux, which is produced in the form of a fine powder for joining metal parts.

The substance goes into a fluid state of aggregation when heated to more than 700° C, which is why it is called high-temperature solder.

The technical characteristics of the flux are described by State Standard 842977, which indicates the dissolution of borax in water followed by solidification of a transparent glassy mass.

General information

Technical borax - sodium tetraborate, is an inorganic compound, fine-crystalline white powder. Consists of a strong base and orthoboric acid.

It is extracted from periodically drying up salty natural reservoirs as a result of artificial synthesis. Flux is available for joining cast iron, copper and steel elements. Additives of copper, brass or silver strengthen solder joints.

Borax, or in other words, borax, melts at a temperature of 750-900 ° C. After transitioning to a fluid state, it crystallizes with the release of specific substances that clean the edges of the parts being connected from dirt, dust, and traces of oil.

Borax melt also prevents the formation of oxidative reactions.

Borax, when mixed with orthoboric acid in equal proportions, creates boron flux. After combining the components, the latter are ground in a porcelain cup and filled with warm solvent.

The liquid evaporates over low heat, leaving a solid form. Fluoride or chloride salts help to obtain a more active flux.

Pros and cons of flux

Solder is most often used when repairing or rebuilding copper piping. Therefore, the advantages and disadvantages of flux should be considered from the point of connection of copper elements.

Borax has the following advantages:

• articulated elements can have different initial temperatures;
• the weld bead is reliable even when soldering metal and non-metallic objects;
• the high degree of heating of the flux still does not allow copper parts, which have a higher melting point, to warp;
• Borax allows you to improve the characteristics of the weld;
• capillary soldering is shown to be the best operation when connecting elements.

With some soldering skills, even a novice welder can create an even and durable seam.

The disadvantages of using borax are as follows:

• when the solder hardens, salt deposits form on the elements being connected, which must be periodically cleaned off;
• Solder is a substance that actively absorbs moisture, even when in a closed container.

Perhaps a novice welder will not be able to immediately select the required amount of borax to obtain a good welding bead.

Usage

Before connecting parts, you need to pay attention to their preparation. The latter is in the following sequence:

1. Clean the joints of the elements from dirt and corrosive damage using a scraper with coarse bristles. The flux itself will deal with the oxide film on the surface.
2. Use a blowtorch flame to heat the joints of the structures to be welded.
3. During heating, leave a gap of at least 1 mm between the elements.
4. Introduce borax with solder into the gap, also heated by a lamp, while continuing heating.
5. When borax crystallizes, turn off the blowtorch.
6. After the parts have cooled, remove salt deposits with a brush.

The first soldering with borax may not be successful due to the small amount of the substance. It is recommended to select it practically. To improve the seam, you can use boron flux with the addition of fluoride or chloride elements.

Source: https://prosvarku.info/rashodnye-materialy/flyus-bura-dlya-pajki

Drill for soldering brass, copper or aluminum and flux: what are they for and how to use

Borax is a powder that is added to so-called high-temperature flux mixtures for soldering metal products. The melting point of borax is quite high – 700 – 900°C.

Soldering borax is very convenient in technical use, all its properties are well known, convenient and described in a special regulatory document - GOST 8429-77.

How to make borax for soldering

Metal soldering is a method of creating a permanent connection of parts using solders. Today, soldering is available with soft and hard solders. Borax soldering involves the use of borax as a flux during soldering, mostly with brass and silver solders. Borax due to its composition dissolves quite easily in water.

During combustion, borax turns into a glass mass, and its melting point ranges from 700-900 degrees. C. During the borax soldering process, salts are formed that must be removed by mechanical cleaning.

Borax is a high-temperature flux used to join materials such as steel, cast iron, copper (its alloys) using medium-melting copper, brass, silver and gold solders. Molten borax allows you to dissolve metal oxides and clean the surface of metal parts being soldered. After using borax and soldering, it is necessary to remove any remaining salt.

Borax together with boric acid when mixed in a 1:1 ratio forms boric flux. Thus, you need to thoroughly mix the ingredients and then grind them in a porcelain mortar. Next, you need to heat the solvent in distilled water, then evaporate to a solid residue. To obtain a more active flux for soldering copper or other metal, you need to add fluoride and chloride salts to the mixture.

Soldering copper pipes using borax

Modern water supply systems in homes are often made of copper. In this regard, it is advisable to be informed about possible actions regarding plumbing repairs, the properties of copper and much more that may be associated with this material.

Advantages of brown copper soldering:

• Possibility of connecting metal parts in any combination;
• Possibility of connection at any initial temperature of the metal product;
• The ability to create a strong and high-quality connection of metal (copper) with non-metals;
• Possibility of desoldering most ready-made connections;
• More precise maintenance of the shape and dimensions of the metal product, since the base metal does not melt;
• Possibility of obtaining excellent interaction between soldered parts and solder;
• High strength and decent performance during capillary soldering.

Soldering technology makes it possible to obtain a connection in several stages:

• Preparation of connections for soldering;
• Removing contaminants, as well as oxide films from the surfaces of metal parts subject to soldering, using flux in the form of borax;
• Heating the metal parts being connected to a temperature equal to the melting point of the metals of the base material;
• Introducing a liquid strip of solder into the gap between the metals being joined;
• Interaction between the parts being connected and the solder;
• Crystallization of the form of solder that is found between parts.

Soldering procedure

Materials and equipment you will need:

• Steel brushes for cleaning the inner walls of copper pipes;
• Pipe cutter;
• Brush for applying borax (flux paste);
• Tin solders;
• Flux paste (borax);
• Gas-burner.

Selecting a device

Burners come in several main types: with and without piezo ignition, for various gas cartridges. It is worth noting that burners from expensive manufacturers (brands) without piezo ignition are not very popular. Thus, you can use inexpensive gas burners of Polish brands, but with piezo ignition.

Please note that piezo ignition is beneficial to a craftsman who wants to solder copper pipes on his own, since such a device will save time and nerves.

1. First, you should clean the inner surface of the connection with a brush;
2. Using sandpaper, we proceed to cleaning the outer surface of the pipe until the copper shines beautifully.
3. Using a special brush, we apply flux (in our case, flux is borax) to the internal as well as the external surface of the joints, and then insert them one into the other.
4. The next stage requires extreme caution, attention and concentration of the master, since the work will be carried out with a gas burner, that is, with an open fire. Thus, we light the gas burner, and then heat the joint. The clutch area should be heated for 15-20 seconds.
5. Next, we take tin-lead solder and run it along the edge of the connection of the two parts. It is worth noting that it is not at all necessary to apply solder along the entire edge of the connection, since half the processed perimeter will be quite enough. The procedure should last at least 3 seconds.

Source: https://crast.ru/instrumenty/kak-sdelat-buru-dlja-pajki

How to solder metal using borax

Soldering of metals is carried out by first removing traces of oxides from their surface. Fluxes are used for this. They should prevent oxidation when heated and encourage good flow of molten solder.

For soldering copper products, borax solder ideally meets all requirements. The substance has been known since the Middle Ages. It was mined in the lakes of India and Tibet, then transported to Europe, where it was used for processing fabrics and leather, and producing glass.

Borax is widely used for working with metals. When manufacturing or repairing metal products, borax soldering is carried out. First of all, the method is used for parts made of copper and brass. A special type of this flux is used when repairing jewelry.

Composition and properties

The exact origin of the historically established, trivial name has not been fully clarified. According to the chemical nomenclature, borax is a crystalline hydrate of the sodium salt of tetraboric acid.

If the composition contains 10 water molecules, then the substance is called sodium tetraborate decahydrate. There are types of crystalline hydrate with five water molecules.

They are called sodium tetraborate pentahydrates. Strictly speaking, the composition of borax is a salt surrounded by a hydration shell of 10 water dipoles.

At 64 ℃, the decahydrate melts and gradually loses water. Complete dehydration of borax occurs at 380°. The resulting tetraborate withstands heating up to 742° and only then melts.

This gradual melting of borax is somewhat confusing to ordinary consumers who are accustomed to the fact that the substance melts strictly at one temperature value. The specificity is explained by the presence of water molecules in the crystalline hydrate. This feature simplifies the use of borax for soldering.

The quality of the substance is standardized by the state standard. There are two grades of raw materials that represent technical borax:

• Grade A is 99.5% salt decahydrate. The remaining 0.5% consists of carbonates, sulfates, and tiny amounts of lead and arsenic compounds;
• grade B - 94% decahydrate, the impurity content of which is 6%.

Both brands are not very stable. The shelf life of technical borax should not exceed six months. It is recommended to use grade B borax as a flux. It fully meets the soldering requirements and is cheaper than grade A raw materials.

Advantages and disadvantages

Borax-based flux is very popular. This material is always on sale. For soldering copper products, borax is the most affordable flux with budget prices.

Borax is also used for soldering certain types of steels and jewelry alloys. Solders containing copper or silver are suitable for the process. Solder seams can always be simply unsoldered if necessary.

Depending on the elemental composition of the parts, you can use not only crystalline powder, but also a solution. Crystalline hydrate is highly soluble in water.

There are some difficulties when using borax. The solder area is covered with plaque after soldering is completed. It needs to be mechanically cleaned.

The shelf life of the material is limited; it must be stored in a dry place. Despite this, borax remains in demand in production and in the home.

Application of brass and copper powder

Practitioners often use flux that has been stored longer than expected. To solder with brass, the borax must be re-melted. The cooled powder should be placed in a jar with an airtight lid. Neglecting this procedure can ruin the work due to waste accumulated during storage.

At the beginning of soldering, the working area must be heated to a clearly visible red color . Heating should begin first at the edges, and then directly at the soldering site.

Then the heated area should be gradually sprinkled with flux, wait until it spreads in the form of a film along the edges of the part. At this point, the heated brass solder must be dipped into the molten borax so that it is covered with a hot flux film.

As experience shows, the soldering area is red in color, while the borax melt is colored bluish. You cannot keep solder in the flux for a very long time. Oxide residues may form.

Then you should warm up the work area again. The brass will take on an orange glowing appearance. You can proceed directly to soldering. If done correctly, the solder will fill all the gaps.

The soldering area will turn golden. When the process is completed, the hot zone should be sprinkled with borax powder and left to cool. Copper parts in a hot (200 ℃) state can be placed in a mixture containing equal parts acetone and water, or simply in water. It makes sense to immerse the cutters in hot sand.

A correctly made connection has a transparent film with a slight blue tint. There are no solder drops on it. If soldering is performed incorrectly, the seam becomes covered with a black porous crust.

The reason may be overheating of the working area, as a result of which slag is formed, or poor quality of borax-based flux. This is how brass and other copper-containing alloys are soldered.

Application of solutions

For lighter metals, a borax solution is used. Working with liquid flux is much easier; you just need to dip the part into it and start soldering. Jewelry, contacts, wires, and other small parts are soldered in a similar way.

Sometimes the presence of borax alone in the flux is not enough. In such cases, mixtures are used for soldering. A common additive that helps cope with the problem is boric acid.

Usually acid and borax are taken in equal parts. Sometimes zinc fluorides, potassium chlorides, and salts of other alkali metals are used. The powders are thoroughly ground with a pestle in a porcelain mortar. You can take a mortar from another material, the main thing is that it does not absorb the borax mixture.

For any soldering, the ends of the parts are first cleaned . This can be done with sandpaper, a stiff brush or a file. Then add a thin layer of powder.

The solution can be applied with a brush or by simply dipping the part. Then the working area is heated evenly, without achieving melting of the parts, and soldering is carried out with the required solder. It should spread well at the junction in a thin layer.

The process can be easily done at home. In production, a soldering station is convenient for constant work. There are several types of installations with different configurations.

They are produced in our country and abroad. You can always choose a model that suits the set of functions and cost.

Copper pipe connection

Copper pipelines are expensive. The investment can be justified with careful installation, which is often carried out by capillary soldering using borax as a flux.

It is worth noting that today, other fluxes are sold that are more convenient to use. One pipe is inserted into the second or fitting so that the gap does not exceed 0.4 mm.

Soldering time is short, 3 minutes. It is important that the parts remain stationary during operation. In order for the borax powder to stick to the surface, the copper is first heated with a torch.

For pipes with a diameter of up to 108 mm, the soldering process is carried out at low temperatures not exceeding 450°. The seam is wide (up to 50 mm), but not very strong. Wide pipes with a diameter greater than 159 mm are soldered at high temperatures. Only professionals can perform the procedure.

In both cases, the solder melt penetrates well into the capillaries of the parts, which contributes to the formation of strong connections. It is recommended to remove any remaining borax.

It must be remembered that soldering is accompanied by the formation of smoke, so you can only work in ventilated areas.

Source: https://svaring.com/soldering/flus/bura-dlja-pajki

Borax flux for soldering: how to use, GOST

Borax is a flux used to join metal parts by soldering. Borax, which is produced in powder form, belongs to the category of high-temperature fluxes, since its melting point is in the range of 700–900°. Borax powder, the characteristics of which are specified in the relevant regulatory document (GOST 8429-77), dissolves well in water and, when heated, turns into a glass mass, which provides protection for the soldering zone.

Borax crystals can be transparent or grayish, but always have a characteristic “bold” shine.

Features and advantages of drill flux for soldering

Borax is a high-temperature flux produced in powder form and used when joining metal parts by soldering. Borax soldering flux melts at a temperature of 700 degrees Celsius, which is why it is called high-temperature flux.

Borax has its own GOST that regulates its composition and production. According to this GOST, borax should dissolve in water and, when solidified, turn into a transparent mass. In this article, we will tell you everything about borax powder.

articles

• What is borax
• Advantages and disadvantages
• Peculiarities
• Instead of a conclusion

What is borax

Borax soldering flux is a powdery substance similar to salt and has the chemical name sodium tetraborate. Consists of boric acid and a strong base. It is synthesized naturally, mined in salt deposits of lakes. Using borax you can solder cast iron, copper and steel. To obtain a strong and durable connection, solder made of copper, brass or silver should be used as a soldering material.

Borax melts at a fairly high temperature. At the same time, it crystallizes and releases substances that clean the surface of parts from contaminants. Borax also protects against oxidation. When performing soldering, it is advisable to use refractory materials such as borax soldering flux. Due to its natural origin, when melting, borax releases salts that must be removed from the surface of the weld after completion of work.

Peculiarities

How to use borax in your work to get the highest quality results? To answer this question, we will talk about all the stages of soldering using borax. First of all, you need to prepare the metal. Clean it from dirt and corrosion. Pay special attention to stubborn stains; they must be removed with a rough brush. The oxide film does not need to be removed, since the borax will handle it itself.

Then, using a blowtorch, you need to heat the surface of the parts to be welded. Leave a small gap between the pieces. Add borax and solder into it, preheated with a blowtorch. Once the borax begins to crystallize, you can stop heating. When borax hardens, it becomes transparent and forms a lot of salts. Remove them from the metal surface.

It is important to follow the sequence of operations and not to overdo it with the amount of flux.
It's hard to say how much borax to use because it depends on the metal and the weld you want to create. Experiment and with experience you will begin to understand which dosage is preferable. 
Borax can be used in powder form, or boron flux can be made from it.

Boric flux is widely used for soldering copper pipes and cast iron parts. Mix boric acid and borax in a one to one ratio. Then you need to crush the resulting mass in a bowl, and then evaporate it, getting rid of excess liquid. Fluoride and chloride salts are added to the dry residue.

Boric flux is ready! It has active properties, allowing you to solder copper parts faster and with better quality.

Instead of a conclusion

As you can see, borax soldering flux is widely used by experienced and novice welders, since its advantages more than outweigh its disadvantages. Be sure to try borax in your work and tell us about your experience in the comments. Share this article on social networks so that other craftsmen can learn more about soldering materials. Good luck!

Source: http://home.nov.ru/osobennosti-i-preimushhestva-flyusa-bura-dlya-pajki/

Using borax for brass soldering

Currently, [borax for soldering] is actively used with silver or brass solder.

In general, any soldering of various types of metals is a method of connecting metal elements together using high temperatures and a variety of solders.

If they talk about brown soldering, they mean the use of this composition as the main flux.

To solder metal in this case, silver and brass solder are mostly used.

It acts as a kind of electrode and allows you to work with steel, brass, copper, and silver.

It is quite simple to use if you know the technology of the soldering process and have an understanding of the characteristics of various groups of metals.

During the combustion process, the borax itself becomes a viscous glass mass.

It should be noted that the melting point of this type of solder is about nine hundred degrees Celsius.

At the time of soldering, this high-temperature flux forms salts on the metal surface, the removal of which can only be done by mechanical cleaning.

Currently, borax can be purchased at any hardware store at an affordable price.

Soldering copper elements

This chemical composition is very often used for soldering copper pipes and other copper materials at home.

It should be noted that in almost every home you can find some elements in the plumbing system made of copper.

Before repairing such elements using borax, it is recommended to study the properties of this material and study the soldering technology.

This high-temperature flux has a number of advantages. First of all, it can be used at any temperature of the product.

In addition, using this electrode, it is possible to connect a metal with a non-metal. The connections made with this solder can be unsoldered at any time without any difficulty.

It should also be noted that the parts themselves and the solder have excellent interaction with each other.

In addition, the dimensions and shape of the product itself do not change in any way, since with this electrode the base metal is not subject to deformation and melting.

This metal soldering provides a strong and fairly reliable connection.

It should be noted that borax should be used in a certain sequence. First of all, you should carefully prepare the surface itself at the soldering site for work.

IMPORTANT TO KNOW: Methods for quality control of welds and joints

To do this, it is necessary to completely remove all contaminants from the surface, remove the formed oxide film, which is very convenient to do with a flux in which borax is the main element.

Next, it is imperative to carefully introduce liquid solder into the gap formed by the elements.

At this moment, there is a tight interaction between the parts themselves and the solder itself. After this, the solder begins to gradually crystallize.

If all the work is done correctly and in accordance with the technology, the connection will be strong and reliable.

Preparation of tools and material

In order to perform brown soldering, you should prepare the necessary equipment for the job. First of all, to perform the relevant work you will need a good cutter exclusively for copper parts.

You should also have a special brush on hand, with which you can conveniently apply borax flux paste.

In addition, you will need tin solder, the borax itself in the form of a paste, and a burner. There are many different types of torches that can be used for soldering.

Burners equipped with piezo ignition or gas cartridges are equally suitable. You should not use expensive torches without an ignition function, as they do not add convenience to soldering.

When performing soldering using a drill, a certain procedure must be followed.

So, first you need to thoroughly clean the surface where the connection is made, for which you can use a special brush with metal fibers.

If pipes are to be soldered, it is necessary to clean them internally. It is also recommended to perform a final cleaning until the metal shines.

This can be done using fine sandpaper. Next, apply borax flux with a brush, both on the internal and external surfaces of the pipe.

After this, it is necessary to compress the soldered parts together as tightly as possible.

All subsequent work must be carried out with extreme caution and in compliance with safety precautions, since open fire will be used.

Before starting work, the burner should be lit, and then thoroughly warm the joint for twenty minutes. Next, the joint is treated with solder, after which the soldering itself is performed.

IMPORTANT TO KNOW: Technique for welding aluminum at home with an inverter

In this case, brass wire should be used for the additive. At the time of soldering, the borax itself is poured in the required quantity directly onto the place where the materials are soldered.

When carrying out work, you can use a graphite electrode, while using extreme caution. The borax soldering process itself does not take much time and is quite simple.

Source: https://rezhemmetall.ru/bura-dlya-pajki-latunyu.html