How to Tin Steel Correctly - Metals and Their Processing

How to solder steel with tin?

Soldering stainless steel is a rather labor-intensive procedure, but it will not cause any special problems if you know all the features of its implementation.

With significantly less labor, it is possible to solder stainless steel alloys that contain no more than 25% chromium and nickel.

Moreover, soldering stainless steel with such a chemical composition allows you to obtain reliable connections of products from dissimilar metals, excluding alloys with magnesium and aluminum.

Solder repaired bicycle frame

Soldering stainless steel, which contains a significant amount of nickel, can be difficult. This is due to the fact that in such alloys, when heated to a temperature of 500–700°, carbide compounds appear. The intensity of the formation of such connections depends on the duration of heating, so soldering should be performed as quickly as possible.

To minimize the risk of the formation of carbide compounds in the stainless steel structure during soldering, titanium is added to the alloy composition, and after the joint is formed, the product is subjected to heat treatment.

You should be very careful when soldering cold-worked stainless steels, the surface of which may become cracked under the influence of heated solder. To avoid such consequences, it is necessary to eliminate the load on the parts being connected during the soldering process.

In addition, it is possible to pre-anneal the products being joined.

Use a gas torch for annealing.

The choice of solder with which to solder stainless steel is influenced by both the chemical composition of the alloy and the process conditions.

So, if this process is carried out at high ambient humidity, then silver alloys should be used, which contain a small amount of nickel.

Soldering in an oven, as well as in a relatively dry atmosphere, is performed using chromium-nickel and silver-manganese solders.

The most common type of flux used when soldering stainless steel is borax, applied to the future joint in the form of a paste or powder.

Melting borax on the surface of the parts being joined contributes to uniform and most accurate heating of the area of the future seam to the required temperature - 850°.

Only after the required heating temperature has been reached, which can be determined by the color change of the future joint to light red, is solder introduced into the joint between the parts.

The flux is applied in an even layer over the entire surface, which must first be cleaned.

After soldering is completed, flux residues are present at the joint, which are removed by washing with water or sandblasting. To perform this procedure, you cannot use nitric or hydrochloric acids, which, although they effectively clean the flux remaining on the surface of the parts, have a negative effect on both the base metal and the used solder.

How to do soldering at home

Problems such as joining stainless steel parts using soldering and soldering stainless steel to copper are often encountered at home.

Products made of stainless steel have been actively used in everyday life for many years, therefore, when for some reason they become unusable, any home craftsman has a natural desire to repair them himself.

It should be said right away that soldering stainless steel parts is not so difficult, the main thing is to strictly adhere to the technology, as well as stock up on the appropriate tools and consumables.

Master the soldering technique on simple connections, and then try working with more critical parts

Before you start soldering stainless steel, it is very advisable not only to study the theoretical material on this issue, but also to become more familiar with the rules for its implementation using training videos.

To solder stainless steel products, you will need the following tools and consumables:

a soldering iron powered by electricity with a power of at least 100 W;
special soldering acid, which will be used as a flux;
file or sandpaper;
solder, specially designed for joining steel parts, based on tin and lead;
cable made of steel;
metal tube.

Soldering materials and tools

When choosing a soldering iron for working with stainless steel, you should opt for a tool with a power of 100 W. Using a more powerful device to perform such work is simply not practical.

The process of soldering stainless steel parts is carried out according to the following algorithm.

First of all, it is necessary to thoroughly clean the area of the future connection, for which sandpaper or a file is used.
After preparing the surfaces of the parts to be joined, it is necessary to apply flux to them, which, as mentioned above, uses soldering acid. The main task of the flux is to ensure high-quality tinning of the parts to be joined.
After the surfaces of the parts to be joined are treated with flux, it is necessary to tinning them, which consists of applying a thin layer of solder consisting of tin and lead to them. If tinning was not successful the first time, then it is necessary to repeat this procedure, preheating the parts to be joined.
Even after heating the products and re-processing them with flux, tinning may not be successful - the solder will simply roll off the surface of the parts, rather than lie on them as a thin film. In this case, you need to use a brush with metal wires, which can be easily made from a tube and steel cable. Before using such a brush, it is also necessary to apply flux (soldering acid) to the surface of the parts and only then, heating the future joint with a soldering iron, clean it with a metal brush. This simple technique allows you to effectively clean the surface of a stainless steel from an oxide film, which, as a rule, is the main obstacle to high-quality tinning.
Once a thin layer of tin has been applied to the products to be joined, you can begin to solder them. This procedure is performed using a soldering iron and solder, which is used to fill the joint between the parts.

Solder Types

Stainless steel products can be soldered with both soft solders made on the basis of tin and lead, and hard types of filler material, which includes more refractory metals.

Soft solder, due to the fact that it is based on tin, is a low-melting material characterized by high ductility and fluidity in the molten state. What is especially important when soldering stainless steel products is that it has good deoxidizing ability.

Properties of soft solders

More reliable connections both in production and at home can be achieved by soldering using hard solders.

The metals from which they are made melt at a higher temperature than tin, which makes it possible to obtain reliable and durable connections with their help.

Very often, materials of this type are produced on the basis of technical silver, which can contain up to 30% in their composition.

Main brands of silver solders

One of the popular types of hard solder is the HTS-528 material, which is successfully used for soldering not only stainless steel, but also copper, brass, bronze, nickel and other metals. Conveniently, it is produced in the form of a rod, the surface of which is already covered with a layer of flux. When working with such solder in a production environment or at home, you should keep in mind that its melting point is 760°.

HTS-528 solder is a rod coated with red flux. In addition to stainless steel, it is suitable for cast iron and non-ferrous metals

Flux preparation

When soldering stainless steel, you should be very careful about choosing a ready-made flux or the recipe for making it yourself. The classic flux composition, which can be prepared at home, includes the following components:

borax (70%);
boric acid (20%);
calcium fluoride (10%).

Steel 092gs characteristics

For soldering small-sized products, you can prepare a flux that will consist only of borax and boric acid mixed in equal proportions. Having mixed the components of the flux in dry form, it must be diluted with water and treated with the resulting solution at the site of the future connection.

Useful tips

To perform stainless steel soldering efficiently, you should use the recommendations of experienced specialists.

The power of a soldering iron, which must effectively heat the metal being joined, is in the range of 60–100 W, but it is better to opt for a 100-watt device. To solder large parts, such as stainless steel pipes, you will need a gas torch rather than an electric soldering iron.
When choosing an electric soldering iron, it is better to opt for models equipped with tips that do not burn.
The most economical and universal type of solder, which makes it possible to obtain high-quality connections for stainless steel products, is tin-lead rods. If you are soldering dishes that will come into contact with food or liquids, it is better to use pure tin as solder, which does not contain harmful impurities.
The room in which soldering work is carried out must be well ventilated.
When performing soldering, be sure to use personal protective equipment so as not to harm your health.

What else you should know about soldering stainless steel

In cases where special requirements are imposed on soldered joints of stainless steel products, special grades of solders can be used, which include materials based on nickel and phosphorus, as well as nickel, chromium and manganese.

Solders of the second group are used, in particular, in cases where soldering is performed in a protective gas environment consisting of a mixture of argon and boron trifluoride.

When performing soldering using this technology, pure copper can be used as solder, which wets the metal well and forms a reliable connection.

When using copper solder, the soldering area will differ from stainless steel in a characteristic yellow color

Nickel-based solders make it possible to obtain joints with high strength. However, such materials also have disadvantages, which include low ductility.

That is why such filler material is not used to connect stainless steel structural elements that will be subject to shock and vibration loads during their operation. In addition, a soldered seam made of such a material is very critical to low temperatures.

Soldering with nickel group solders, which melt at temperatures exceeding 1000°, can be performed in dry hydrogen, argon and vacuum.

Thus, soldering stainless steel products (large pipes operated under pressure, dishes, pieces of furniture or interior design) has its own nuances, which must be taken into account when choosing both soldering modes and consumables. There are many reference books, guided by which, you can optimally select all the necessary materials and obtain a high-quality, reliable and beautiful soldered connection.

Source: https://varimtutru.com/kak-payat-stal-olovom/

How to tin metal correctly

> Electrician's tips > How to properly solder with a soldering iron with acid

Most often, for soldering printed circuit boards in radio engineering products and household appliances, they prefer to use ordinary pine resin rosin, but it can be replaced with other components. When molten, it promotes the spreading of tin solder along the copper traces of the board.

This allows you to reliably solder the legs of radio components and the ends of connecting wires. Rosin allows you to effectively solder copper, tin and silver products.

In order to solder galvanized and stainless iron, radiators, buckets, pans, various alloys, brass and other metals, you can use acid solutions.

Bottle with acid solution for soldering metals

Acidic solutions

It is important to choose the right acid solution. It depends on the type of metal from which the parts are made. This could be an aluminum or copper radiator, a kettle that needs to be soldered, copper, brass or roofing iron:

Galvanized iron. Places where it is necessary to solder are treated with an acid solution, correctly called (zinc chlorate). This composition can be bought in specialized stores; the easiest way is to prepare it yourself.

To do this, it is enough to throw pieces of zinc into 100 ml of hydrochloric acid, which can be removed from the body of AA batteries. After the chemical reaction is completed, the zinc will dissolve, releasing a large amount of hydrogen.

It is correct to carry out the process in a well-ventilated area, in the absence of open flame.

After the solution has cooled and settled, the upper transparent yellow part is poured into a clean glass container. The sediment is poured into the ground; it is not recommended to drain into sewers with metal pipes. Acid can damage pipes and seals. The remaining part of the solution is ready for processing galvanized iron roofing.

How to solder sheets of roofing iron

Stainless steel. Before soldering, the surface is cleaned and treated with phosphoric acid, which contains the following elements:

up to 50% zinc chloride;
ammonia up to 0.5%;
dissolves in water with a pH concentration of 2.9%.

Phosphoric acid is used for soldering as a flux and for cleaning metal from rust.

The solution can be transparent, light yellow or colorless; when heated to 213ºC, it is converted into H4P2O7 (pyrophosphoric acid), which degreases the surface of metals. The composition dissolves the oxide film on various metals and alloys:

stainless steel;
brass;
Nickel alloys;
copper alloys;
alloys of carbon metals and low-alloy steel.

Application of acids

To solder metal products (pipes, radiators, buckets, pans), the surface of the elements is thoroughly cleaned, using a file or sandpaper. An acid solution is applied to the cleaned areas with a brush, after which solder is melted to a liquid state on the surface with a soldering iron.

How to solder correctly with a soldering iron

Liquid solder tins the cleaned areas; when boiling, the acid flux comes to the surface. When the solder hardens, the soldered elements are securely and hermetically fixed.

You can solder with a powerful soldering iron or an open flame 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.

Remains of acid flux are washed off with water, preferably a soapy, alkaline solution, this will prevent further corrosion of the metal.

Machined and brazed stainless steel elements

Acid can damage skin and muscle tissue, and inhaling vapors can damage the respiratory organs. When contacting air, hydrochloric acid enters into a chemical reaction, and smoke is visible above the open container. To work correctly in these conditions, wear safety glasses, rubber gloves, a gas mask, or a respirator.

If the solution gets on the skin, wash this area of the body with a 6% alkaline solution or plain soap. It is not recommended to solder radio circuit boards with fluxes containing acid. The acidic components are difficult to wash off and contribute to the breakdown of copper tracks. It is better to replace them; there is a special paste for this.

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Soldering acid solutions should be stored correctly in containers made of the following materials:

glass;
ceramics;
porcelain;
fluoroplastic

Such dishes do not react with acid; the prepared composition can be stored in it for a long time.

Soldering without a soldering iron

At home, if you don’t have a soldering iron, you can solder copper wires with a diameter of up to 2 mm. For soldering radiators and utensils, special solder, blowtorches, and gas torches are used, since the copper rod of the soldering iron is not able to heat a large surface area. There are several ways:

Tinning and soldering wires in molten solder . The wire is first heated, applied to a piece of rosin, it melts and spreads evenly over the surface of the connection. The wire is twisted and lowered into molten solder in a tin can over a fire; it can be heated with a blowtorch. In order to solder the twist, it is advisable to hold it in boiling tin for up to 1 minute. The copper wires will heat up and the alloy will fill all the gaps between the twisted wires. In this way you can solder small parts made of copper, brass and other alloys.

Tinned and soldered copper wire

Soldering wires in the trench . The stripped and twisted wires are laid in a 2-3 cm piece of aluminum tube, 0.5-1 cm in diameter, sawn lengthwise. The top is filled with a mixture of fine shavings of solder and rosin dust, and from the bottom this structure is heated with a lighter, candle or small blowtorch.

Heating the solder with a blowtorch (torch)

The mixture melts and thoroughly envelops all wire connections. After hardening, the aluminum gutter is removed and the joint is insulated.

Solder shavings can be sharpened with a coarse file.

A thin copper wire up to 0.75 mm can be laid on aluminum foil, sprinkled with a mixture of rosin and tin shavings, wrapped tightly and heated for 3-4 minutes. The solder will evenly fill all the elements at the soldering site; after cooling, the foil can be removed and discarded.

How to prepare solder paste

Soldering paste is sold in radio parts stores, but you can prepare it yourself. To 32 ml of hydrochloric acid add 12 ml of ordinary water, then pieces of zinc - 8.1 g. For this, enamel dishes are used.

How to tin a soldering iron: preparation and care of the soldering iron

After the dissolution reaction is completed, tin – 8.7 g is added to the composition. When the second dissolution reaction is completed, the water is evaporated to a paste-like consistency of the solution. The paste is transferred to a porcelain container, where powder is poured, which contains:

lead – 7.4 g;
tin – 14.8 g;
dry ammonia – 7.5 g;
zinc – 29.6 g;
rosin – 9.4 g.

This paste is mixed with 10 ml of glycerin, heated and stirred.

How to solder correctly, sequence of actions:

The parts at the soldering site are cleaned, the wires are twisted;
the paste is applied with a brush in a thin layer;
the surface for soldering is heated with a plasma lighter, torch, candle or alcohol tablet, or even with matches or over a fire until the paste melts;
After melting, the soldering elements are removed from the heat source, and the solder hardens.

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.

Soldering utensils

How to install a socket with your own hands correctly

Buckets and pans with holes no more than 5-7 mm in diameter are recommended to be soldered without using a soldering iron with POS-60 solder. Leaky places on the dishes can be reliably 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 areas are treated with a solution of soldering acid with a brush.

In order to prevent solder leakage from the outside, all bottoms or individual places where holes need to be soldered are covered with thin tin plates. Powdered solder and rosin are poured into the cleaned holes from the inside. The soldering areas are heated over an open fire until the solder melts and fills all the cracks.

For radiators, stripping and soldering are carried out from the outside. To prevent solder from leaking inside, the hole is covered with a plate of tin, galvanized iron, or 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 completing the soldering process of radiators, the internal and external surfaces are thoroughly washed with an alkaline, soapy solution in order to prevent the effect of acidic components on the metal.

Bottle with flux for soldering aluminum

When it is necessary to solder aluminum parts, special solders are used:

4:1 mixture of tin and zinc;
30:1 mixture of tin and bismuth;
99:1 tin and aluminum powder.

The sequence of surface treatment is the same as for preparing iron utensils. In order to properly solder aluminum, rosin is added to the powder, but the melting point must be above 500ºC. It is recommended to stir the solder in the hole, using a thin copper soldering iron tip.

PCB soldering paste

The composition is not much different from the paste that is used to solder without a soldering iron; the powder includes the following components:

tin – 14.8 g;
rosin – 4 g;
zinc dust – 738 g;
lead powder – 7.4 g.

For a paste-like consistency, add diethyl ether - 10 ml, it can be replaced, use glycerin - 14 ml.

Soldering sequence:

the legs and tracks of the printed circuit board are cleaned;
in order to solder, the legs of the parts are inserted into the holes of the board;
places where it is necessary to solder on the board are lubricated with paste;
the paste is heated with a soldering iron until it melts;
The solder spreads and hardens, providing reliable electrical contact between the parts and the traces of the printed circuit boards.

Soldering lessons.

You can learn how to solder correctly by watching this video.

From the above information it follows that, if desired, and if certain materials are available at home, you can solder in various ways, achieving high-quality fastening of parts and tightness of containers.

Soldering copper pipes using a torch

You can solder with or without a soldering iron almost all metals, alloys, aluminum, brass, copper, electrical circuit wires for various purposes, metal utensils, radiator housings and other pieces of equipment.

Source: http://ooo-asteko.ru/kak-pravilno-ludit-metall/

How to solder steel parts

Often there is a need to fasten steel parts without drilling and without welding. Soldering steel will help. But how to do it correctly, because there are special nuances here. A few recommendations from experts.

What kind of steel solders well?

Some grades of steel lend themselves well to soldering, while others are soldered with great difficulty and do not want to be combined with any solder or with any flux. As a rule, soft steels "for nails" are easy to solder. At the everyday level, this can also be explained by the fact that the material is dotted with microscopic craters and irregularities. But there are also electrical grades that are especially hard and elastic, and are used for shafts and precision mechanics. It's your luck here

The question is that it is impossible for a home craftsman to determine the brand by eye. You can only find out how well a given part made of steel, or an alloy close to it, is soldered by experimentation.

How to make a tin connection - procedure

It all depends on how successfully the part can be tinned and how strong the contact of the tin solder with the steel is. In order for the contact to be satisfactory, if possible at all, the following must be done:

steel stripping, chemical stripping under solder;
heating the part to the melting temperature of the solder, keeping the solder on the part under flux for some time in a fluid state.

Cleaning the steel is first done mechanically, using sandpaper, to remove layers of rust and dirt. Then a composition that reacts well with iron oxides is used as a flux.

The most harmless to use, but effective in this case, is orthophosphoric acid, which can be easily purchased at a car store as a “rust cleaner.”

The required power of heating devices depends entirely on the mass of the parts.

The process of soldering two steel parts

If you need to solder two large nails, then the power of one soldering iron 100 W will not be enough. To heat up a large nail or a similar weight steel part clamped in a vice, you need to use a hair dryer. Or a gas burner.

You will also need cotton wool on a stick to supply flux to the heating zone, and a soldering iron of 50 W or more.

The sanded steel is heated with a burner.
Phosphoric acid is applied to the hot part and molten tin solder is immediately applied with a soldering iron.

As a rule, steel parts that can be soldered develop a very strong bond with tin, i.e. When the metal is coated, it is tinned.

The same is repeated with another detail. Then the two parts located together are heated, and additional solder is applied to the contact area with a soldering iron.

How strong is the soldering of steel, can it be made stronger?

The strength of such a connection will be determined by many factors:

strength of bond between solder and metal,
connection area,
direction of the load in relation to the welded planes.

But in any case, the strength of tin soldering cannot be compared with what is commonly understood as the strength characteristic of steel or “metal welding”.

You can strengthen it by using another solder - special strong and more refractory compounds containing silver, zinc, copper, etc.

Another direction for increasing strength is to cover with solder not only the plane, but also the sidewalls of the part - covering the part with solder. Then the pull-off resistance under multidirectional loads will be greater.

Extra strong soldering, special solders

To use compounds that provide a strong connection with steel, with its own melting point of about 800 - 900 degrees, you need to use a graphite crucible.

The work should only be carried out by specialists in metal smelting. It is necessary to know the basics of metal melting, the procedure for handling melts and safety precautions. In general, soldering of steel with heavy-duty solders is performed at specialized enterprises.

Possible solder composition:

55% zinc, 45% copper, some silicon to increase fluidity.

The composition is melted under a layer of coal in a graphite crucible. Steel parts to be soldered are heated with a gas burner. Phosphoric acid is used as a flux. The melt is fed to the parts. As a rule, tinning and soldering are carried out during one heating of both the parts and the solder.

But such soldering of steel is more complex than simple welding.

Source: http://stroy-block.com.ua/material/623-kak-payat-stalnye-detali.html

The process of tinning a soldering iron tip: how to tin new and copper coatings, correct work with solder

The need to tin a soldering iron arises when a molten drop of solder stops spreading over the heated surface and sticking to it; there is no way to supply a sufficient portion to the soldering point, which interferes with high-quality work.

The tip, receiving heat from the heater, oxidizes in air. In addition to reducing the adhesion of solder to copper, a layer of thermally insulating carbon deposits impairs heat distribution.

There are a number of ways to tin a soldering iron for the purpose of periodic maintenance of the working tool; such a procedure is also required for a new tip and one that has oxidized during storage.

Basic information about the tinning process

Tinning is divided into initial, carried out on a new or long-stored soldering iron, and working, performed immediately before soldering.

How to tin a soldering iron tip? First, the tip is mechanically cleaned of scale, oxide film, slag and other contaminants, then a thin layer of molten solder, most often tin-based, is applied to the prepared surface.

For mechanical cleaning the following are used:

abrasive stone;
sandpaper;
another soldering iron.

Cleaning a soldering iron with a non-burn tip

For inexperienced soldering workers, craftsmen recommend starting with a file. As the solder strengthens his skills, he selects the most convenient stripping methods for himself.

Soldering iron sharpening

The soldering iron tip is sharpened with a file at an angle of 30-40 degrees.
The edge is left 1 mm wide and slightly blunt.
On a new soldering iron, you only need to sand the tip with fine sandpaper to remove the patina. Patina is a greenish copper oxide.
If store-bought sharpening is not satisfactory, then you need to remove the tip and forge it yourself, giving it the shape of a concave blade. This method has one more advantage - the metal will become less susceptible to corrosion.
To give the sting a finished look, all that remains is to process it with a finely cut file.

Preparation and Maintenance

The more intense the work, the sooner the soldering iron tip burns out and becomes overgrown with scale scales.

During prolonged heating to high temperatures, the copper from which the tip is made partially transforms into molten tin, and partially abrades on the soldered surfaces and contacts. Physical and chemical erosion of the substance occurs. In addition, under the influence of heat, an oxidative reaction of copper with atmospheric oxygen occurs. On models that allow you to regulate the temperature, it is recommended to reduce it when there are breaks in soldering, or simply turn off the soldering iron during this time.

Sequence of operations to remove scale:

Carefully remove the sting.
Clean off the scale layer with fine-grained abrasive paper.
Apply a graphite protective layer to the tip by rubbing it with a pencil lead. This will slow down the reappearance of the scale layer.
Lightly tap the body of the electric heater and turn it to remove scale from the recess for the copper rod.
Insert the tip back into the mount.

To ensure electrical safety, each time before starting work, you should inspect the insulation of the network cable for the absence of mechanical damage and melting.

From time to time it is also useful to measure the insulation resistance value. The measurement is taken between the plug contacts and the tip. The value must be greater than 10 mOhm.

Why tin and sharpen

Tinning the tip before soldering significantly simplifies all operations with a soldering iron, which consist of transferring molten solder to the contact area. This procedure can only be avoided if the purchased soldering device has a tip covered with a protective film of silver.

The silver-based coating holds solder well without compromising the thermal conductivity of the copper base.

However, products with such a coating cost a lot of money; In addition, the silver film comes off over time and exposes the copper base (they say that it dissolves in the solder). So in this case, after some time, the sting will have to be tinned, one way or another.

It is necessary to sharpen the tip with a file not only before tinning, but also in cases where it is necessary to give the tip a shape convenient for work.

Some users prefer the tip to be sharpened to a cone. Others try to sharpen its side parts in such a way as to obtain a flat, pointed shape.

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Features of the sting

The sting is the main (and only) working part of the device. It is heated by an electric heater and heats the solder, rosin (or other flux) and the parts to be soldered. During operation, an invisible oxide film forms on it, reducing the wettability of the material. Visually it looks like this: tin or rosin does not spread evenly over the entire area, but collects in a drop and flows down.

The size and geometry of the working body are chosen so that they correspond to the operations performed. So, when soldering parts of large sizes and thickness, choose a powerful soldering iron with a thick tip. To install microcircuit legs, on the contrary, a particularly low-power device is required, with a thin tip and good grounding, so as not to damage sensitive components due to static charge or overheating.

Soldering microcircuits

A universal soldering iron is sharpened with a spatula. Thin parts are soldered with the narrow side, and more massive ones with the plane of the blade.

Overlapping sheet metal soldering

In the process of repairing car bodies and all kinds of various tin works, the need arises for soldering sheet metal overlay. There are two ways to stack sheet parts on top of each other: by tinning them first, or by using soldering paste that contains flux and solder.

In the first case, overlapping areas of parts after mechanical cleaning and degreasing are pre-tinned. Then the parts of the connection are applied to each other with degreased surfaces, fixed with clamping devices and heated from different sides using a soldering iron to the melting temperature of the solder. Evidence of successful soldering is the flow of molten solder from the gap.

After preparing the parts in the second method, the contact area of one of the parts is coated with a special solder paste. Then the parts are fixed in the desired position, tightened with clamps and, as in the very first case, the seam is heated on both sides with a soldering iron.

When purchasing solder paste, you need to pay attention to its purpose, since many solder pastes are intended for soldering electronics and do not contain active fluxes that allow steel to be soldered.

How to tin a soldering iron with a copper tip

Tinning a soldering iron is a simple job and usually does not cause any difficulties. If the surface of the rod is well prepared and cleaned, then both tin-lead and silver solders fit well on it.

Soldering iron with copper tip

It is necessary to clean the surface of the rod to the condition of a new part. First you need to work with coarse sandpaper, level the surface and give it the required shape. If it is technically possible, it is a good idea to polish the surface - this way it will oxidize more slowly.

There is another technique - binding. To do this, the tip should be pulled out of the heater and, like a blacksmith, forged with a hammer on an anvil (or a massive vice). A surface compacted in this way will also oxidize much more slowly.

After machining, it’s time to actually tin the tip. Experienced shareholders recommend various methods:

Place a few pieces of solder in the rosin can. Heat the soldering iron and dip the stripped tip into it. Rosin melt will act as a flux additive and will prevent the metal from becoming coated with an oxide layer. Instead, it will be coated with a layer of tin. Next, you need to take a square of coarse natural cloth and wipe the freshly tinned tip. In this case, the tin will rub over the surface and stick to it perfectly. The disadvantage of this method is a lot of smoke and a strong smell.
The next method of tinning the tip produces less smoke, but requires more labor. A piece of coarse natural cloth should be laid out on a smooth board, sprinkled with crushed rosin or a whole piece should be placed on it. Dip the stripped tip into rosin and rub the surface with a solder rod. This operation will have to be repeated several times, and then rub the working surface on rosin cloth.

A soldering iron with a copper tip must be tinned each time before soldering and always after storage without use.

Special means

As special agents, it is allowed to use active organic mixtures (fluxes), as well as pastes of a special composition. The use of fluxes makes it possible to increase the efficiency of wetting the tip material with solder and, accordingly, improve tinning performance.

Domestic manufacturers offer several types of flux, which are available for public sale in hermetically sealed plastic packaging. When working with a composition consisting of ethyl alcohol with added catalytic additives, the temperature in the processing area does not exceed 300 degrees. This indicator satisfies the requirements for choosing the correct tinning mode for most materials used for the manufacture of tips.

The procedure for using active paste additives differs only in the way they are applied to the surfaces being treated.

Source: https://instanko.ru/drugoe/kak-zaludit-payalnik.html

How to solder steel with tin - Metalworker's Guide

Soldering stainless steel is a rather labor-intensive procedure, but it will not cause any special problems if you know all the features of its implementation. With significantly less labor, it is possible to solder stainless steel alloys that contain no more than 25% chromium and nickel. Moreover, soldering stainless steel with such a chemical composition allows you to obtain reliable connections of products from dissimilar metals, excluding alloys with magnesium and aluminum.

Solder repaired bicycle frame

In addition, it is possible to pre-anneal the products being joined.

Use a gas torch for annealing.

The choice of solder with which to solder stainless steel is influenced by both the chemical composition of the alloy and the process conditions. So, if this process is carried out at high ambient humidity, then silver alloys should be used, which contain a small amount of nickel. Soldering in an oven, as well as in a relatively dry atmosphere, is performed using chromium-nickel and silver-manganese solders.

The most common type of flux used when soldering stainless steel is borax, applied to the future joint in the form of a paste or powder.

Melting borax on the surface of the parts being joined contributes to uniform and most accurate heating of the area of the future seam to the required temperature - 850°.

Only after the required heating temperature has been reached, which can be determined by the color change of the future joint to light red, is solder introduced into the joint between the parts.

The flux is applied in an even layer over the entire surface, which must first be cleaned.

Soldering iron with tin solder

The soldering process is the chemical joining of two metals using solder. Moreover, the crystal structure of the metal does not change. That is, the connected parts remain with their technical characteristics.

The connection itself is quite reliable, but much will depend on the type of solder and soldering technology. In addition, it should be noted that not all metals can be joined by this process. Basic metals, especially steel (iron), can be soldered together.

Three technologies

There are three technologies for soldering iron with tin:

soldering iron To do this, you will have to use soft solders with a high lead content;
blowtorch. This will require hard solders with a high tin content;
electrical soldering of iron.

The first method is used if the iron will not be subjected to heavy loads during operation. The second is tinning of iron with tin, when tin solder is applied to the surface of a metal product and rubbed over its entire plane in a thin layer.

This technology requires soldering flux. The third option is used on a production scale, for which special equipment is used.

Soldering sheet metal

Soldering tin (thin sheet iron) is a common process in the manufacture of metal containers. But often, even at home, it is necessary to fasten sheets of iron together, assembling sealed structures. Therefore, before soldering one sheet to another, you need to prepare everything you need.

For the process of soldering iron with tin, you will need solder with a small concentration of tin, for example, POS-40, flux, a soldering iron and an awl.

In the process of soldering iron, flux acts as a solvent and an oxidizing agent at the same time. That is, the metal is immediately wetted and protected from oxidative processes. Rosin and hydrochloric acid or zinc chloride and boric acid are used as fluxes.

As for the soldering iron, for high-quality tin soldering it is better to choose an electric tool with a power of more than 40 W. The old soldering tool, which is heated by the flame of a fire, is practically not used today, even at home.

Sequencing

Here are the main stages of this process:

cleaning of joined sheets;
applying flux;
heating up the soldering iron and tinning;
soldering with tin;
cleaning the joint with gasoline.

Cleaning is carried out mechanically with sandpaper. If the contamination is large, you will have to treat it with a solvent. If it is not possible to clean it using this method, then etching is carried out with sulfuric acid.

Two pieces of sheet iron are brought to each other at a distance of 0.3 mm. Their edges are treated with paste-like flux using a brush. The soldering iron tip is cleaned with sandpaper, and the tool itself is plugged into the electrical network through an outlet. To check whether it has heated up well, you need to place its tip in the ammonia mixture, which should boil.

Now the stage of tinning the iron is carried out. That is, using solder made of tin or its alloy, the edges of two sheets of tin are processed in order to cover them with a tin layer, which will perform protective functions against metal corrosion.

Everything is ready, all that remains is to solder the two ends of the sheets. The soldering iron tip is brought to the joint along with the tin solder, and they both move smoothly along the joint boundary.

In this case, the tip must be pressed not with a sharp end, but with a flat edge, due to which the parts being connected will warm up at the same time, which will affect the high quality of the iron soldering..

Features of working with galvanized products

Soldering galvanized tin in a purely technological process is no different from the previous one. But the technology has its own subtle nuances that affect the quality of the final result.

You cannot solder galvanized steel with solders that contain large amounts of antimony. This substance, when in contact with zinc coating, creates a weak seam.

It is better to use boric acid and zinc chloride as flux. If the products themselves have already been tinned with tin during the production process, then rosin can be used as a flux.

When a connection is made between galvanized iron (sheet) and wire, the latter must be bent at a right angle to increase the contact area of the two products.

The rest of the process is carried out exactly the same. By the way, it doesn’t matter whether the wire was made of galvanized or ordinary steel.

There are several more important points that must be taken into account in the process of soldering galvanized products. If solder rods based on tin and lead are used for soldering iron, then it is better to add flux based on zinc chloride and ammonium chloride. The ratio is 5:1 respectively.

Tin and cadmium based solder requires caustic soda as a flux additive.

If galvanized iron products, the protective layer of which contains more than 2% aluminum, are connected to each other, then solder based on tin and zinc is used. And hydrochloric acid and petroleum jelly (stearin) are used as flux.

Regardless of which parts or assemblies are connected by soldering, it is necessary, after the process is completed and the seam has cooled, to rinse the joint with water to remove any remaining flux.

Safety precautions

Soldering iron with tin is an unsafe process. Therefore, precautions must be strictly observed. Protective gloves are put on your hands, and a stand must be installed under the soldering iron so that the heated tip does not touch the table and available materials. And the procedure itself must be carried out carefully.

Despite the apparent simplicity of the soldering operation, it is actually a serious procedure. And you need to treat it with great attention. Something was missed, they were even applied incorrectly, and we can assume that the quality of the joint has dropped sharply. Therefore, it is important to approach each stage responsibly, especially when it comes to cleaning two joined iron products.

Source: https://svaring.com/soldering/tehnologii/pajka-zheleza-olovom

Tinning and soldering of car body

Welcome to the kuzov.info blog!

In this article we will look at how tinning and soldering of a car body is carried out.

Tinning and car body brazing have been used in automobile manufacturing and repair since the mid-1930s.

Lead solder was used in the mass production of automobiles to be applied to the lap weld joints of roofs and rear fenders.

Applying solder to the body for many years, before the advent of automotive putty, remained a traditional method of repairing a damaged car body (see article on the history of the invention and development of putty).

Content:

The process involves applying special solder to body panels to fill in imperfections, seal and mask weld joints, and solder holes.

While putty is most often used in modern auto body repairs, solder is still used in classic car restorations. In fact, both tinning and putty have their advantages and disadvantages.

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The main disadvantages of using solder for body repair are the difficulty of its application and heating of the body. There is nothing too complicated in this process, but you need to follow some rules and acquire skills. When the burner is used correctly, the heating is quite gentle.

Even the paint on the back side may remain intact. Putty wins in this sense, since it is applied to the surface easier than solder. In terms of characteristics, solder is much superior to putty. We will look at its benefits in this article below.

The solder is softened by heat and applied to the surface prepared by tinning. After cooling, a strong bond between the solder and the metal surface is formed.

Soldering the body may be necessary where other repair methods are difficult or impossible. Solder is convenient to use when the metal is too thick to straighten and there is no access from the back of the panel.

Solder can be used in areas where there may be slight metal movement during vehicle operation and the putty may crack (welding joint). Solder seals the weld seam well and guarantees its corrosion resistance.

Also, when using body solder, the thickness of the layer is not as critical as when using putty. Solder is well suited for areas of the body where you need to form an edge.

Advantages of tinning and soldering the body

Solder sticks to the surface better than putty. The tensile strength (the force required to separate the solder from the metal it is applied to) is 423 bar. This is a very high figure.
Even a thick layer of solder does not shrink, unlike putty.
Solder has better elasticity and strength than automotive putty.
Lead bends well together with the metal on which it is applied, so it does not crack.
The solder will not crack or peel off on impact, as happens with putty.
Solder is waterproof. Putty cannot be called completely waterproof.
Solder can withstand high temperatures, so it can be used for repairs and subsequent powder coating.
Another big advantage of solder over putty is that you don't have to worry about the hardening time. You can add additional solder directly onto the already applied layer.
You just need to heat the surface and new solder and add it. There is no need to completely melt the already applied layer.

Types of solders for body repair

There are different types of solders. For body repairs, soft (low-melting) solders are often used. They are sold in the form of rods, 45 cm long, of different thicknesses. In general, they are classified as lead free or lead free solders. The first type of solder was used for many years due to its ease of use. However, it has been banned in some countries for use in mass production due to health and environmental concerns. However, lead solder is still used by individuals and can be found commercially. Many craftsmen prefer to use lead solder.
The ratio of its components (tin, lead) is indicated on the solder. Traditional body solder is 30% tin and 70% lead. May contain an additional component, for example, 74% lead, 25% tin and 1% antimony. Lead is hazardous to health. To use it, protective equipment is required and safety precautions must be taken into account. However, it is easier to use. It remains soft longer after heating (in the range of 180 to 260 degrees Celsius). This makes it easier to apply and level. This solder is easily applied to vertical and horizontal surfaces. Once lead solder has hardened, it is not recommended to process it with a grinder, as very toxic dust is generated. So, it is usually processed with a special body file, and at the final stage with a block of coarse sanding paper by hand. If you still use a grinding machine, then you need to use only coarse abrasive so that there is no suspension of fine dust. Lead residues after grinding must be disposed of immediately.

Solder containing lead (Pb 74%), tin (Sn 25%) and antimony (1%).

Solder can have different lead to tin ratios (70/30, 60/40 or 50/50). Solder with lower lead content is also used in auto body repairs, but has a low ductility range (183ºC to 188ºC) so it is more difficult to use. Solders with this ratio are usually used on horizontal surfaces, since they quickly become liquid and can flow. The adhesion of all lead solders is approximately the same and depends on proper surface preparation.
As an alternative to lead solder, safer lead-free solder has been developed. In all lead-free solders, tin is the main component. The other component may be silver, copper, indium or bismuth. Most lead-free solders have either a higher or lower melting point than lead solder. For body repairs, the most common lead-free solder is a mixture of tin and silver (94% tin and 6% silver or 96% tin and 4% silver). It has a higher cost. Lead-free solder is approximately equal in performance to traditional lead solder with a 50/50 (lead/tin) ratio. This solder has a higher melting point (221°C). Once heated, it remains soft for less time than lead solder, making it more difficult to align. When hardened, it becomes harder and more brittle. It is more difficult to process with a file. The advantage is that it can be sanded as it does not produce toxic dust. Although, do not forget about the respirator. An additional benefit of lead-free solder is higher tensile strength.
Solder used in electronics typically consists of 60% tin and 40% lead. It may contain flux in the center. Rosin flux, often used with this solder, does not promote adhesion to steel, but acid flux may work well. This solder is best used only for soldering small holes, since its ductility range is very small.
To work with aluminum bodies, a different type of solder (containing tin and zinc) is used.

What is flux? What flux should I use for tinning the body?

The purpose of the flux is to facilitate the soldering process and ensure the strength of the connection between the solder and the metal of the body. One of the barriers to achieving successful soldering is surface impurity (contamination and oxidation).

Contaminants can be removed by mechanical cleaning, but oxidation increases with increasing temperature, impairing solder adhesion to the repair surface. The metal has a thin layer of oxides or sulfides, no matter how clean it appears.

The purpose of the flux is to remove this layer and should prevent the formation of a new oxide layer during solder application.

Flux not only prevents oxidation, but also provides dry cleaning and performs a wetting function by reducing the surface tension of the molten solder, helping it flow better over the surface. This way, the solder will not stick to an unprepared metal surface; it will form balls. On the prepared surface, the solder spreads and sticks normally.

Flux paste for tinning.

Flux paste is used for tinning the body. It is a kind of primary soil. It contains acid (zinc chloride or hydrochloric acid) and solder in powder form.

The acid chemically cleans the surface and removes oxidation, converting it into a soluble salt, while the powder simultaneously eats into the metal, leaving a very thin layer (tin or tin with lead) that improves solder adhesion when applied to the repair area.

After application, the paste needs to be heated and the residue wiped off with a rag.

The flux paste is activated by an acid (zinc chloride or hydrochloric acid) and must be removed after soldering is completed. If the flux is based on hydrochloric acid, then it can be neutralized with water and soda, and then washed with clean water. If the flux contains zinc chloride, then acetone will be required for neutralization. You can also use sodium dichromate.

Particles from the flux paste can remain in the pores and small cavities of the weld, which can cause corrosion. Therefore, before tinning and applying solder, it is necessary that the holes and recesses be welded.

What tools and materials are needed for tinning and soldering the body?

There are special kits that include the solder itself, flux paste, tools for leveling the applied solder and instructions. Also, all accessories can be purchased separately.

Set for tinning and soldering the body.

Source: https://kuzov.info/luzhenie-i-payka-kuzova-avtomobilya/

Hot technologies

Hot tinning is carried out using two methods: immersion and rubbing. In the first case, a metal product is immersed in a bath of molten tin. In the second, the alloy is applied to the plane of the product and tow is rubbed over it in a thin layer.

These methods have been known for a long time, the technologies have been worked out to the smallest detail. They are simple and do not require complex equipment, devices and tools.

When they talk about tinning and soldering, they often mean the hot method. But this technology also has its disadvantages. Firstly, it is tin that is unevenly distributed over the surface of metal products.

This is especially true for the method of immersion. Differences in one plane can be significant, especially if the product has a complex design. Therefore they have to be modified.

If you are tinning metal with small diameter holes or fine cuts, then the hot option will not work here.

And the third disadvantage of hot tinning is the difficulty of removing contaminants that form inside the alloy and remain inside the half. These impurities come with the solder, so it is important to use a high purity tin alloy.

Galvanic technology

The galvanic option of servicing is also divided into two methods: in alkaline and acidic electrolytes. The name suggests that the process of applying tin is based on the use of electric current.

Hence the cost of the process. But it is this technology that guarantees strong adhesion of the applied alloy to the metal surface. There are other positive aspects:

the tin layer is smooth and uniform;
you can set the required coating thickness, even on the most complex metal structures;
low porosity of the coated layer;
saving tin solder.

Typically, products with complex shapes are tinned using alkaline electrolytes, because this version of tinning has high covering and dispersive power.

The disadvantages of galvanic tinning technology include the fact that this method is complex. It can be carried out by highly qualified workers, and this costs wages. That is, it is impossible to tin the metal using this method at home. In addition, the process requires special baths.

If we talk about tinning technology with alkaline electrolytes, then the solution itself is unstable, it is difficult to prepare, and you will have to constantly monitor the alkali concentration and the quality condition of the anodes.

Preparation of products

The cleaner the metal surface, the more firmly the solder will attach to it. Therefore, depending on the requirements for the workpiece itself, different methods of preparing metal for tinning are used.

The first method is to clean the metal surface with brushes. Typically, this tool removes scale and rust. First, the product is washed with water and then cleaned with a brush. Lime, sand, and pumice are often used at this stage.

The next way to prepare for tinning is to grind the metal with sandpaper and discs. This stage is the finalization of the product, that is, bringing its surface to maximum evenness.

Degreasing is used using sodium compounds: sodium hydroxide – 10-15%, sodium phosphate – 10-15%, sodium carbonate – 10-15% solution. Let us add that chemical solutions must be heated to 50-80C before use.

Etching is also used. For this, sulfuric acid is used.

Features of rubbing and immersion

Rubbing tinning technology basically involves a process where solder is applied to a metal product and rubbed with tow. In this case, flux is used in the form of ammonia and zinc chloride. Here is the sequence of operations:

zinc chloride is applied to the metal and heated with a blowtorch;
when it boils, solder is added to it, which melts;
ammonia in powder form is sprinkled on top;
then the liquid tin is rubbed with tow over the surface of the metal product.

For the immersion method, tin baths are used, in which the tin is heated to +300 ℃. A metal product is lowered into the molten alloy and covered with a layer of solder.

Moreover, the longer it lies in the bath, the thicker the layer of tin will settle on it. When tinning a soldering iron, you first heat it up, then dip it in rosin, and only then melt it with a small piece of tin, thereby providing a coating.

Solution for galvanic treatment

In principle, both tinning technologies (with alkaline and acidic electrolytes) differ from each other by the presence of an alkaline or acidic solution in the electrolyte bath. The process of tin adhesion is the same for them, and it occurs with the help of electric current.

The composition of acidic solutions includes tin sulfate, sulfuric acid, substances of boilillary-active type (phenol or cresol), colloidal substances (glue, nicotine, gelatin or similar substances).

It is very important to accurately observe the proportions of the main components: tin sulfate - 65 g/l, sulfuric acid - 100 g/l.

As for alkaline solutions for tinning metals, their diversity is not determined by one recipe. Therefore, the composition of the solutions is different. Some use tin chloride, others sodium stannous, and others stannous chloride.

The same applies to solvents. There is caustic sled, sodium acetate, and caustic potassium. You can choose your own solution recipe based on the presence of certain components.

Moreover, each will necessarily have its own concentrations of substances. Of course, the current density and heating temperature of the solution in the bath are selected for each recipe.

Tinning, as a protective process for metals from corrosion, is one of the most popular. It is not very cheap, but it is effective compared to many technologies. Therefore, it is often used in various industries.

Source: https://respect-kovka.com/kak-pravilno-ludit-metall/