Why a soldering iron does not solder well: how to tin a soldering iron and prepare it for work
Category: Soldering, Articles 10/15/2018 · : 0 · Reading time: 3 min · Views:
Why doesn't solder stick to the soldering iron?
The main and main reason for this problem is very strong carbon deposits on the soldering iron tip. The fact is that if there is no solder or flux residue on the soldering iron for a long time when it is turned on, then a dense layer of soot forms on the surface of the tip due to oxidation, which can no longer be cleaned off with a desoldering sponge. This is why solder rolls off the soldering iron tip.
Causes of soot
Some beginners or those who are used to working with copper tips make a fatal mistake. They clean the soldering iron tip with sandpaper, files or blades from a stationery knife. This is only true for uncoated copper tips.
This method is unacceptable in principle for “eternal” stings.
There is a high risk of damaging the outer layer of the tip (a thin metal alloy), which can lead to cracks and further destruction. In addition, despite its appearance, the soot layer itself does not exceed some microns.
So how to clean a soldering iron from such deposits? There are several ways.
Easy sponge cleaning
The easiest way is to clean the tip with a metal sponge. Small metal shavings clean the tip from carbon deposits without damaging the coating. Such sponges are sold in any smartphone spare parts store, as well as in radio stores and online stores (AliExpress, etc.). A kitchen one can also work, but you need something dense and softer. In addition, it will be worse to clean.
An even more affordable recovery option
By soldering you can remove a layer of carbon deposits. We make a small bath of solder. You will need a solder rod and flux. Preferably activated (for example, LTI - 120). You can even use regular alcohol rosin. This is in the case of “light” soot, of small size.
Now we divide the solder bar into small pieces and pour a little rosin or flux (even if you have solder containing rosin, this is not enough for this case).
And we begin to bathe the tip in solder. If the solder does not melt, then you need to increase the temperature.
We coat the tip in solder from side to side, without pulling it out, so that the tip is completely enveloped. In a couple of minutes, a small amount of carbon deposits will evaporate, and it will be possible to take a little more fresh solder onto the tip after “bathing”. We leave the soldering iron heated with a drop of water for 10 - 15 minutes.
When doing this work, thoroughly ventilate the room! If the carbon deposits are still difficult to clean off after several attempts, then now you need to use soldering acid. The procedure is the same.
Sting activator to help
Even if it didn’t work out with solder, there is still one more way - this is an activator for the tips. Like the metal sponge, it is available in radio stores and can also be purchased on AliExpress. The principle of operation is simple - dip the tip of a working soldering iron into the activator for a couple of seconds and clean it with a sponge after that.
After removing the carbon deposits, you need to apply solder to the tip as soon as possible. even in a few seconds it can burn (if, of course, your soldering iron temperature is over 340 ℃)
Tips for caring for your soldering iron
- Do not leave the soldering iron turned on for a long time without solder or flux on the tip;
- Clean the tip only with a desoldering sponge or a metal sponge, which also removes carbon deposits;
- Do not clean the sting with sandpaper , a knife, or a scalpel. There is a risk of damage to the coating;
- If you solder with acid , be sure to clean the soldering iron after soldering; do not leave it to cool with acid!
Useful videos on the topic
Source: https://tyt-sxemi.ru/payalnik-ploho-payaet/
How to solder (change) surface mount BGA chips?
› Equipment repair › How to solder (change) surface mount BGA chips?
Almost all modern electronics, including tablets, laptops, smartphones, etc., contain surface-mount chips on their motherboards. The design of such microcircuits differs in that instead of the classic wire leads, it contains a ball array.
That is, a certain number of metal contact points, which in fact represent pieces of solder in the form of small balls. Such balls, accordingly, cannot be inserted into traditional holes on the board, but BGA chips can be soldered to mounting pads. This is surface mounting.
Let's look at how to solder BGA chips, as well as the necessary equipment for the job.
Replacing surface mount chips
It would seem that surface mount integrated circuit technology requires a unique mechanical approach. Looking at such a chip installed on the motherboard of a laptop or other equipment, it is difficult to imagine how, for example, you can replace a chip at home if it fails. However, as practice shows, home repairs with BGA (Ball Grid Array) replacement are quite possible.
How to solder a microcircuit constructed using BGA technology - a chip that is simply applied to the surface of a printed circuit board? It turns out it's not difficult at all
Of course, you need to have some skills in repairing electronic equipment and soldering skills in microcircuits, in particular. You will also need a certain instrumental and material base:
- electric soldering gun,
- auxiliary infrared heater,
- miniature vacuum pump with suction cup,
- special flux,
- electric soldering iron,
- other auxiliary tool.
In addition to the entire designated material base, an important component in the soldering of surface-mount BGA microcircuits is a special flux - a paste-like substance.
What is flux for soldering BGA chips?
In fact, soldering flux for surface-mount microcircuits is a chemical (acidic) compound, thanks to which high-quality “cleaning” of soldering areas is achieved. There are two types of paste-like (gel-like) fluxes:
- Fluxes requiring subsequent cleaning.
- Fluxes that do not require cleaning.
Meanwhile, in any case, you should still resort to cleaning the board from flux residues after completing all work, thereby preventing possible destruction of the PCB structure in the future. It should be noted: almost all fluxes intended for soldering surface-mount microcircuits (BGA) can be washed quite easily.
Flux, a substance used when soldering surface-mount chips, looks like this consistency. Typically packaged in plastic syringes for ease of use
The commercial market offers a wide selection of materials of this kind for working with surface-mount microcircuits. In particular, a rich assortment is presented on the well-known Chinese portal Aliexpress. Moreover, the prices of Chinese goods are significantly lower than branded European ones, and the quality is quite consistent.
If desired, it is possible to make flux yourself using a certain set of substances:
- glycerin (a mixture of glycerin and aspirin),
- acetic acid (ammonia),
- alcohol solution of rosin,
- wax.
However, it is preferable to use a ready-made commercial product.
Infrared motherboard heater
Additional heaters, for example, an infrared desktop device with automatic temperature setting, are used to warm up the motherboard from the bottom side relative to the installation of the BGA chip.
In this way, uniform heating is achieved during the process of soldering (replacing) a surface-mounted BGA microcircuit, and deformation of the motherboard PCB structure is eliminated.
The Chinese portal Aliexpress is full of such ceramic panels of infrared radiation, which are proposed to be used under the tool for lower heating of electronic boards
However, digital infrared heaters are quite expensive (from 5,000 rubles), so for home use (individual, not large-scale repairs) it is more logical to use simple ceramic infrared plates for soldering BGA microcircuits.
An upper heating tool is used together with bottom heating. In particular, the traditional tool here is a soldering iron - a modern-style electric soldering iron, “sharpened” for soldering (desoldering) miniature elements of electronic boards.
Electric soldering gun for surface mount chips
This type of soldering tool differs from a traditional soldering iron with a metal tip in that in this case a working tip is not used. Instead of a working tip, the required temperature background in the soldering areas is provided by a flow of heated air. Accordingly, the design of a soldering gun should be considered a kind of air pump, equipped with a heating and control system.
Soldering Station
One of the many design options for a soldering station that supports the use of a conventional soldering iron with a tip and the operation of a soldering gun
There are soldering guns of various designs and operating capacities. Factory-made structures usually have functions for controlling the strength of the air flow, the temperature of the outgoing air, and allow visual monitoring of parameters. At the same time, it is possible to make a completely tolerable soldering iron from an ordinary electric soldering iron by performing some modernization of the design.
Source: http://poleznyblog.su/kak-paiat-meniat-mikroshemy-poverhnostnogo-montaja-tipa-bga.html
Types and features of choosing a soldering iron tip
Even such a simple tool as a soldering iron has design features that consist of individual elements. The sting has the smallest size. The performance of the device depends on the quality level of this part. If you are not interested in this, then you can simply buy a soldering kit, use the instructions and not think about which soldering iron tip is best. But if you are curious and think that you can figure this out on your own, then read on.
Tip properties
The working tip has the following properties:
- Thermal conductivity. A very important parameter that determines how much heat will be transferred to the work area from the heating element;
- Ability to accumulate heat. This characteristic depends on the size of the tip. A very thin tip, when in contact with a large element, can instantly release heat;
- Wear resistance. Of course, no one will hammer nails with a soldering iron, but over time the tip is subject to wear due to mechanical stress and the influence of aggressive fluxes;
- Protection against oxidative processes. Even a thin oxidizing film significantly reduces the quality of the tip.
From the point of view of heat conductivity, copper alloys are considered the most optimal metal for the tip. But copper is characterized by low resistance to corrosion and wear. Nickel or steel based alloys are the complete opposite. High level of strength, rust protection - but terrible thermal conductivity.
Therefore, modern manufacturers are trying to create tips from a variety of materials in order to adapt to market demands. They also constantly experiment with composite materials, increasing the performance properties of the tool.
Copper products
Most soldering irons are equipped with these tips. The copper product is very versatile and has excellent thermal conductivity. And most importantly - excellent heat capacity.
That is, when processing large parts or soldering thick wires, the collected thermal energy will not sharply change the temperature and dissipate. Therefore, when processing massive elements, specialists prefer to use soldering irons with a large copper alloy tip. To heat such a product, a large amount of energy is required, but its mass ensures stable temperature indicators during operation.
You can solder almost any part with this tip. The only exceptions here are planar microcircuits, SMD modules, etc. Of course, the tip can also be given a thinner shape, but in this case it will wear out quickly.
The main problem with copper alloys is their low level of heat resistance and excessive softness. Also, when exposed to high temperatures, a copper product begins to oxidize. Cleaning the tip using the classical method does not give a positive result. Craftsmen have to clean it using sandpaper or a file, after which the size of the tip is significantly reduced.
For the purpose of keeping the surface of the tip in good condition, it is coated with solder.
Tinning process
To begin with, the product needs to be wiped with a sponge soaked in water, slightly warmed and cleaned with a needle file (fine file) or emery abrasive. After this, you need to place it in rosin, and put a piece of solder on top. The tin alloy itself will begin to coat the surface of the tip.
Another option is to rub the hot tip against the surface of the wood that has solder or flux on it. It is better to choose coniferous wood.
Another problem with copper is its low resistance to corrosion at high temperatures and exposure to fluxes. There is no need to assume that acidic compounds are the cause of all problems. Rosin also has an unfavorable effect on copper. Over time, grooves and microscopic niches appear on the surface of the metal, which must be polished.
One way or another, with regular replacement and proper care, the copper tip is very convenient to use. That’s why soldering irons with such tips are still produced today.
Nickel and silver
In fact, this is the most ordinary copper tip, but with a special coating. To provide protection against burning and corrosion, the surface of the product is silvered or nickel-plated. The only problem is that a metal such as nickel is characterized by insufficient good adhesion, therefore solder melted to a liquid state does not stick to it.
You will only be able to heat the soldering area itself, rather than scooping up a small amount of tin with a soldering iron. In practice, you will have both hands busy - one holding the tool and the other holding the tin wire.
Silver plating does not have these types of problems. At the same time, the price of the device is within reasonable limits, and the quality of the tip improves.
Another solution is a multi-layer tip. In such products, the beneficial properties of materials are used separately. These designs are expensive, but they last a very long time and perform their assigned tasks extremely well.
It is also worth noting that tips with a protective coating must not be cleaned with abrasives, otherwise the protective layer will be damaged and the product itself will quickly break.
Ceramic coating
The body structure is made of strong ceramics, and the tip itself is made of a metal alloy. A material such as ceramics has good heat capacity and thermal conductivity. But it is much stronger than copper alloys and is not afraid of corrosion. By creating tips from composite materials, manufacturers try to combine all the best properties of different materials in one device.
Soldering irons equipped with a ceramic tip are very convenient. They do not need to be cleaned regularly. However, old-time craftsmen prefer copper products.
Compound varieties
This type of tip is composed of several materials at once. For example, the core is made of steel, the heat-conducting element is made of copper, and nickel, like a brass alloy, provides protection against corrosion.
Considering that working conditions can constantly change, for home use it is better to acquire a soldering iron with replaceable tips. The most important thing is to choose the planting depth and diameter.
Temperature stabilizer
Of course, good material alone is not enough for full-fledged work. It is also necessary that there is always a certain temperature at the end of the tip. It is for this purpose that many manufacturers build a special sensor into the body of the sting.
In fact, such temperature control is needed only for fine processing of parts that are very sensitive to strong heat. In this case, the required temperature is set on the tip, and work can be done without fear of damaging the parts. Most designs use the simplest scheme - setting values in advance without subsequent control.
The temperature regulator can be built into the product, or it can be a separate unit that receives data from the sensor. This does not have any impact on the quality of work performed.
Making a thin tip
Some radio amateurs and home craftsmen make their own soldering tools. This happens after they have tried a bunch of options - from expensive German and Japanese ones to nickel-plated pins with gas activators and microwaves from the Middle Kingdom.
To make a good tip, you will need:
- A familiar, experienced turner or access to a machine.
- A copper rod with a diameter of 6-8 millimeters.
- A small amount of silver.
Let's create the foundation. We give the copper rod a shape that matches the hole in the tip holder.
From the end part we make a hole with a depth of ten to fifteen millimeters for the “M4” thread. Then we order from a jewelry store or workshop a silver rod ten millimeters long and five millimeters in diameter. The quality of the precious metal is completely unimportant. We cut a two-centimeter piece from the silver rod, create an “M4” thread, screw it into the base and adjust the shape of the tip.
After processing is complete, you will have a high-quality soldering iron with a thin tip. The copper alloy will supply thermal energy to the silver tip, which has excellent adhesion, so solder will stick to the tip perfectly. For reliability, you can make two tips at once, which can be changed if necessary.
There is only one drawback - over time, silver will dissolve in lead or burn, but this is a long process.
Source: https://ObInstrumentah.info/raznovidnosti-i-osobennosti-vybora-zhala-dlya-payalnika/
Making a thin tip for a soldering iron with your own hands
Despite the fact that many people consider a household soldering iron to be an ordinary tool, it consists of several important parts, each of which performs a specific function. High-quality and coordinated work is simply impossible without the use of specialized soldering iron tips. These parts almost always have a removable shape, which greatly simplifies the work process. After all, from time to time there is a need to replace them.
Varieties of stings
All modern sets of tips for soldering irons differ significantly from each other, it all depends on the material, protective coating, shape and thickness. In addition, each replacement tool can dissipate different amounts of power, which is very important when choosing the most suitable product. Experts say that the most important thing to consider is what material the tip is made of and what shape it has.
As for the material, depending on the tasks, you can use tips with copper, ceramic, copper-steel, brass, chrome or nickel coating.
The shape of the product can also differ significantly: curved, pointed, cone-shaped and even with a cut. As practice shows, it is easiest to use a curved device to remove excess solder, as well as to dismantle parts from the board.
It is the material and shape of the tips that play an important role in the operation of the soldering iron, since the following characteristics depend on them:
- The resulting ability to inject energy at the soldering site. It is this characteristic that determines the possibility of high-quality and uniform heating of the working area.
- The level of thermal conductivity, which determines the final amount of heat supplied from the soldering tool to the working area.
- The degree of resistance of the tip used to oxidation.
A high-quality soldering iron with a replaceable tip must be equipped with a tip made of copper and special alloys. This criterion is due to the fact that the final thermal conductivity of the removable product will be significantly higher than that of steel parts.
But, despite all the advantages, even copper tips have their drawbacks. The main part of them is associated with the low level of wear resistance of the material and the fact that they are susceptible to the negative effects of corrosion. To eliminate these nuances, manufacturers apply a nickel or steel coating to the tip, and the thermal conductivity of the tip changes.
Due to the fact that gas soldering irons are widely in demand both in the private and industrial spheres, manufacturers produce a wide range of tips with different performance characteristics. Thanks to this, you can purchase the most suitable soldering iron rod at an affordable price.
Main advantages
Universal soldering iron tips are distinguished by their versatility and high quality, which is very important for repair work. The great demand for working tips is due to their many advantages:
- The ability to accumulate generated thermal energy. It is worth considering that this factor largely depends on the size of the part. Experts say that a soldering iron with a thin tip gives off all the heat at the first contact with the metal.
- High degree of thermal conductivity. This is one of the most important characteristics. This criterion determines how much heat from heating will be transferred to the main work area.
- Oxidation resistance. The presence of even the thinnest film of oxides several times reduces the ability of the tip to transfer heat to the soldering site.
- Good wear resistance. Of course, no one will use a soldering iron to perform tasks that are unusual for it, but over time, any tip wears out. This is mainly due to negative mechanical effects.
Due to numerous advantages, tips made of nickel alloys can be found in the collection of every master. This is due to the fact that such parts have a high level of strength and resist corrosion well. But the thermal conductivity in this case is at the lowest level.
Self-tinning of the tip
To carry out this procedure at home, you need to wipe the sting with a regular sponge, which should first be moistened in water. After this, the tip must be thoroughly heated and cleaned with sandpaper (in some cases a needle file can be used).
Source: https://pochini.guru/sovety-mastera/izgotovlenie-zhala-dlya-payalnika
Important characteristics of the soldering tip
Even such a simple device as a household soldering iron has component parts, each of which performs its own strictly defined function.
That is why, when studying the structure of this product, they talk about a set of soldering iron tips, which are almost always (except in rare cases) made removable.
The need to change the tip is caused not only by mechanical wear, but also by the need to select the thickness and shape of the tip that is suitable for specific operating conditions.
Types of stings
Replaceable soldering iron tips, differing in material, shape, coating and thickness, are capable of dissipating different amounts of power, which is very important when choosing a product suitable for the job. The material and shape of the tip are of particular importance.
According to the type of material used in manufacturing, all soldering iron tips are divided into copper and copper with steel, nickel or chrome coating.
According to the shape of the tip - pointed, curved, cone-shaped or with a cut. The curved tip is convenient for dismantling parts from the board and removing excess solder.
Important characteristics such as:
- thermal conductivity, which determines the amount of heat transferred by the soldering tip to the working area;
- the ability to accumulate energy in the soldering area, which determines the possibility of high-quality heating of the working area;
- wear resistance and resistance to oxidation of the tip used.
Even a relatively thin oxide film formed on the surface of a removable element significantly reduces its ability to effectively transfer heat energy to the soldering zone.
The most suitable material for a soldering iron tip is, of course, pure copper, as well as well-known alloys made on its basis. From the point of view of thermal conductivity, a copper removable tip is much preferable to a steel one.
However, it is not without certain disadvantages, manifested in the low wear resistance of the material and its susceptibility to corrosion. Therefore, a steel or nickel coating is applied to it, and the thermal conductivity of the product changes.
Adapting to the needs of the market, many manufacturers have mastered the production of a wide range of tips, so purchasing a suitable soldering iron rod is not difficult.
In addition to the technical characteristics and properties of soldering tips discussed above, great importance is also attached to such a parameter as their size.
Tip thickness
This parameter is decisive in cases where an electric soldering iron is used to work with massive products (with large amounts of thermal energy released into the soldering zone).
In contrast, soldering irons with thin tips and different tip shapes are typically used when working with small electronic parts and thin conductors. They are also in demand in the manufacture of jewelry, which involves filigree processing methods.
This parameter is universal and can apply to soldering iron tips made of any material. At the same time, its influence on thermal conductivity indicators for the specified design options is different.
In cases where a significant increase in thermal output is required, preference is usually given to tips made of pure copper.
Availability of protective coating
The main disadvantage of copper products (rapid destruction during the soldering process) can be leveled by applying a special protective coating to their surface. In this way, some hobbyists are trying to get a so-called “long-lasting tip” for a soldering iron.
One of the most effective methods of protection is the use of silver-based coatings, which provide excellent thermal conductivity.
Naturally, such tips also have a corresponding price, but they are very practical in use, since they are well “wetted” with solder. However, the high cost of coatings limits the possibilities of using such tips in everyday life; In addition, the silver coating fades quite quickly at elevated temperatures.
Manufacturers have developed a compromise option that allows you to combine all the best of the considered solutions in one product. They cover only the base of the soldering iron tip with a protective layer of nickel, without touching its working tip, which is protected by a more reliable and expensive material with good adhesion.
They are also made with soldering irons with a ceramic heater and a special non-burning tip, which requires special careful handling. In some cases, the coating may be multilayer, consisting of metal alloys.
Homemade tip for usb model
The choice of tip for working with a soldering iron powered from a USB connector is determined by the amount of power consumed from the source, which is limited by the applied voltage (no more than 5 Volts). In this case, you will need a very thin soldering iron tip, made by yourself at home.
If you have an old purchased product, you can use the spare tip included with the kit.
Almost any craftsman with a minimum of metalworking skills can make a tip for such a soldering iron on his own. To make it, you need to take a copper rod with a diameter of no more than 3 mm and cut a piece of the required length from it.
After this, you should sharpen one of its ends, which is called “to suit you”, that is, in such a way that it is convenient to solder the elements of the circuits with which you will work. The second end of the homemade tip is adjusted in thickness to fit the mounting hole in the soldering iron, or a thread of the appropriate size is made on it.
Protective treatment
The main disadvantage of soldering irons with a copper tip is the softness and low heat resistance of the starting material itself - copper.
At operating temperatures, the surface intensively oxidizes and begins to deteriorate layer by layer. Periodic cleaning of the tip using conventional methods (sandpaper or file) only delays the time of destruction and does not ensure the required safety of the material.
The only way to extend the service life of this part of the soldering iron is mechanical treatment of the surface, which consists of protective tinning (the term “tinning” means covering the surface with a thin layer of solder).
In order to properly tin the tip installed in the soldering iron, you must perform the following operations:
- First, it is wiped with a damp cloth or sponge, after which the soldering device is plugged in.
- After the tip has warmed up to operating temperature, the tip and most of the base should be cleaned with a small file.
- Then you will need to immerse the end of the tip in a jar of rosin and place a small piece of soft solder on top.
Upon completion of this operation, the tin will spread evenly over the working surface of the tip.
There is another method for tinning and cleaning the surface from carbon deposits, according to which a heated tip is rubbed with force several times over a wooden surface with flux and solder residues.
Without first tinning the newly purchased tip, it makes no sense to start soldering, since the solder simply will not “wet” its surface.
Another serious problem that often arises when working with a soldering iron and leads to destruction of the tip is surface corrosion due to the aggressive effects of fluxes.
Combined with high temperatures, this results in the formation of deep pits and grooves that will require additional sanding to remove. As a result of grinding, the working dimensions of the tip are noticeably reduced, so over time it has to be replaced with a new tip.
Despite all these difficulties, with proper handling of the soldering iron and timely care of its working part, you can ensure normal operating conditions for this device.
And having a whole set of additional tips on hand will greatly facilitate all soldering operations.
Source: https://svaring.com/soldering/instrumenty/zhalo-dlja-pajalnika
Brass soldering iron tip - Metalworker's Guide
Such a simple device as a soldering iron has its own design and component parts. The smallest in size, but not in importance, is the sting. The soldering iron’s ability to perform its tasks depends on its quality.
Working tip properties:
- Thermal conductivity. The most important characteristic. It is this that determines how much heat from the heater will be transferred to the work area;
- The ability to accumulate thermal energy. The characteristic is mainly related to the size of the sting. A tip that is too thin will instantly give off heat when it comes into contact with a massive part;
- Strength, or more precisely, wear resistance. No one is going to hammer nails with a soldering iron. However, over time, the tip wears out - under the influence of aggressive fluxes or mechanically;
- Protection from oxidation. Even the thinnest film of oxides sharply reduces the ability of the tip to transfer thermal energy to the soldering site.
The ideal material for the manufacture of a soldering tip (from the point of view of thermal conductivity) is copper or its alloys. The reverse side of the moon is extremely low wear resistance and susceptibility to corrosion.
The direct opposite is steel and nickel alloys. High strength, no corrosion - but disgusting thermal conductivity.
Therefore, manufacturers produce soldering iron tips from various materials, adapting to market demands. They also do not stop experimenting with composite materials, giving tools ever higher consumer properties.
Copper
You can make a good sting from a copper rod
The vast majority of soldering irons are equipped with just such tips. The copper tip is quite versatile and has outstanding thermal conductivity. And most importantly - excellent heat capacity.
This means that when working with massive copper contacts or soldering thick cables, the accumulated heat will not dissipate throughout the workpiece, sharply reducing the temperature. Therefore, for soldering volumetric parts, soldering irons with a copper tip, which weighs several hundred grams, are chosen.
It will take a lot of energy to heat it up, but the mass of the tip will ensure a stable temperature during operation.
There are more elegant copper tips. The classic version of a 40-60 W soldering iron, familiar to many.
With the help of such a tip, you can solder almost everything, with the exception of modern electronic components - planar microcircuits, SMD modules, etc. You can, of course, give a refined shape to the tip - but then the tip will wear out instantly.
Popular: How to solder correctly with a soldering iron, consider common mistakes
The problem with copper is its softness and low heat resistance. At high temperatures the surface quickly oxidizes. Cleaning the tip in the traditional way does not lead to anything. You have to clean it mechanically, using a file or sandpaper. At the same time, the tip rapidly decreases in size.
To maintain the working condition of the surface, it is covered with a thin layer of solder.
How to properly tin a sting
It is necessary to wipe it with a damp sponge, heat it and clean it with sandpaper or a file. Then immerse it in a jar of rosin and place a piece of solder on top. The tin will spread on its own over the clean surface of the tip.
Another way is to rub the heated tip on wood that has flux and solder on it. It is better to choose a tree of coniferous species.
If this is not done, soldering becomes impossible regardless of the heating temperature.
The second serious problem is corrosion from aggressive fluxes at high temperatures. You should not think that acidic compounds are to blame. Rosin also has a detrimental effect on the surface of copper. Over time, cavities and grooves form on the surface, which must be sanded, again losing in size.
However, with proper care and regular replacement, the red metal tip shows very good qualities. Therefore, there is no question of removing it from production.
Fireproof
In fact, this is an ordinary copper tip, only with a coating. To protect against corrosion and burning, the surface is nickel-plated or silver-plated. The problem is that nickel has poor adhesion, so molten solder will not stick to it.
That is, the classic option - scooping up a drop of tin and applying it to the contact - does not work here. You can only warm up the soldering area. Solder supply from the side is required. In reality, this means that both hands will be busy. Soldering iron in one hand, tin wire in the other.
Silver-based coatings do not have such problems. It is perfectly wetted by solder and has good thermal conductivity. But the high cost does not allow mass production of such tips. In addition, silver quickly burns out from high temperatures.
Manufacturers offer a comprehensive solution to the problem. The tip is coated with nickel, except for the working tip. More expensive coatings are applied to it, with good adhesion. At the same time, the cost remains reasonable, and the properties of the tip are improved.
Whole sets of soldering iron tips are offered, with working tips of various shapes.
On the one hand, you have to buy a whole package, on the other, wear and tear occurs much less. Another option is a multilayer tip, which uses the properties of each material for its intended purpose.
This design is not cheap, but it lasts a long time and performs its task efficiently. There are no questions about how to tin the tip of a soldering iron; this process is carried out in a factory environment and does not need to be repeated.
You will learn how to tin a soldering iron by watching this video.
Ceramic
The body is made of durable ceramics, the tip can be metal. Ceramics have thermal conductivity and heat capacity not much worse than copper. At the same time, it is stronger and not subject to corrosion. By making composite tips, manufacturers combine the best qualities of various materials into one product.
Soldering irons with a ceramic tip are more convenient and allow you not to be distracted by regular cleaning. But representatives of the so-called “old school” prefer copper tips. Although, for working with modern radio components of the SMD form factor, copper fits like a bull in a china shop. But a soldering iron with a thin ceramic tip is just right.
Composite
You can use the properties of each material exactly where they appear most clearly. Composite tips combine two, three, or four materials. For example, steel is in the form of a core for strength. Copper - as a heat-conducting material from the heating element to the working tip. Nickel – anti-corrosion coating. The tip is made of silver alloy for better adhesion to solder.
Given the constantly changing soldering conditions, it is wise to have a soldering iron with replaceable tips at home. The main thing is to select the diameter and depth of the tip into the heating element.
Temperature stabilizer
Of course, quality material alone is not enough. It is necessary that the optimum temperature is maintained at the tip of the sting. To do this, a sensor can be built into his body. This option is ideal for maintaining a constant temperature in the soldering area.
In fact, such a circuit is only needed when working with elements that are sensitive to overheating. Then the temperature on the tip is set not a few degrees higher than the melting point of the solder, and you can solder without fear of damaging the parts. Most designs use a simpler scheme - with pre-set temperature without objective control.
Popular: Soldering iron or soldering iron? We make it ourselves
The tip temperature regulator can be built into the housing (if the soldering iron's power supply circuit is inductive), or placed in a separate unit. This does not affect the quality of work. Moreover, the vast majority of work is performed by selecting a soldering iron according to power, that is, “by eye.”
There is a category of radio amateurs who prefer to use tools of their own design, including a soldering iron tip. As a rule, after trying various options, from expensive Japanese or German ones, and your favorite domestic copper ones, to nickel-plated nails from the Middle Kingdom, you will come to the only suitable product. Or try making a sting with your own hands.
In this case, we suggest you look at the following material:
What to make a high-quality soldering iron tip from
For production you will need:
- Access to a lathe or a familiar lathe;
- Copper rod 6-8 mm in diameter;
- A few grams of silver.
Let's make the base. We form the copper rod into a holder for the tip.
At the end we drill a hole 10-15 mm deep for M4 threads. Accordingly, we cut the internal thread.
We order a silver rod with a diameter of 5 mm and a length of 10 cm from a jewelry workshop. This will not take much money, especially since the quality of the metal does not matter; you can take the cheapest silver, even technical silver from contacts. We cut a piece 2 cm long from it, cut an M4 thread, screw it into the base and give the tip the required shape.
After processing, we obtain an excellent composite (composite) tip. The copper supplies heat to the silver tip. Silver has excellent adhesion, so solder sticks to it like glue.
Source: https://ssk2121.com/latunnoe-zhalo-dlya-payalnika/
Construction and repair of an electric soldering iron
An electric soldering iron is a hand-held tool designed for fastening parts together using soft solders, by heating the solder to a liquid state and filling the gap between the parts being soldered with it.
Electrical circuit of a soldering iron
As you can see in the drawing, the electrical circuit of the soldering iron is very simple, and consists of only three elements: a plug, a flexible electrical wire and a nichrome spiral.
As can be seen from the diagram, the soldering iron does not have the ability to adjust the heating temperature of the tip.
And even if the power of the soldering iron is chosen correctly, it is still not a fact that the temperature of the tip will be required for soldering, since the length of the tip decreases over time due to its constant refilling; solders also have different melting temperatures.
Therefore, in order to maintain the optimal temperature of the soldering iron tip, it is necessary to connect it through thyristor power regulators with manual adjustment and automatic maintenance of the set temperature of the soldering iron tip.
Soldering iron device
The soldering iron is a red copper rod, which is heated by a nichrome spiral to the melting temperature of the solder. The soldering iron rod is made of copper due to its high thermal conductivity.
After all, when soldering, you need to quickly transfer heat from the soldering iron tip from the heating element. The end of the rod is wedge-shaped, is the working part of the soldering iron and is called the tip. The rod is inserted into a steel tube wrapped in mica or fiberglass.
A nichrome wire is wound around the mica, which serves as a heating element.
A layer of mica or asbestos is wound over the nichrome, which serves to reduce heat loss and electrically insulate the nichrome spiral from the metal body of the soldering iron.
The ends of the nichrome spiral are connected to the copper conductors of an electrical cord with a plug at the end. To ensure the reliability of this connection, the ends of the nichrome spiral are bent and folded in half, which reduces heating at the junction with the copper wire.
In addition, the connection is crimped with a metal plate; it is best to make the crimp from an aluminum plate, which has high thermal conductivity and will more effectively remove heat from the joint.
For electrical insulation, tubes made of heat-resistant insulating material, fiberglass or mica are placed at the junction.
The copper rod and nichrome spiral are closed with a metal case consisting of two halves or a solid tube, as in the photo. The body of the soldering iron is fixed on the tube with cap rings. To protect a person’s hand from burns, a handle made of a material that does not transmit heat well, wood or heat-resistant plastic, is attached to the tube.
When you insert the soldering iron plug into a socket, electric current flows to the nichrome heating element, which heats up and transfers heat to the copper rod. The soldering iron is ready for soldering.
Low-power transistors, diodes, resistors, capacitors, microcircuits and thin wires are soldered with a 12 W soldering iron. Soldering irons 40 and 60 W are used for soldering powerful and large-sized radio components, thick wires and small parts. To solder large parts, for example, heat exchangers of a geyser, you will need a soldering iron with a power of one hundred or more watts.
Soldering iron supply voltage
Electric soldering irons are produced designed for mains voltages of 12, 24, 36, 42 and 220 V, and there are reasons for this. The main thing is human safety, the second is the network voltage at the place where the soldering work is performed.
In production where all equipment is grounded and there is high humidity, it is allowed to use soldering irons with a voltage of no more than 36 V, and the body of the soldering iron must be grounded.
The on-board network of a motorcycle has a DC voltage of 6 V, a passenger car - 12 V, a truck - 24 V. In aviation, a network with a frequency of 400 Hz and a voltage of 27 V is used.
There are also design limitations, for example, it is difficult to make a 12 W soldering iron with a supply voltage of 220 V, since the spiral will need to be wound from a very thin wire and therefore many layers will be wound; the soldering iron will turn out to be large and not convenient for small work. Since the soldering iron winding is wound from nichrome wire, it can be powered with either alternating or direct voltage. The main thing is that the supply voltage matches the voltage for which the soldering iron is designed.
Soldering iron heating power
Electric soldering irons come in power ratings of 12, 20, 40, 60, 100 W and more. And this is also no coincidence. In order for the solder to spread well over the surfaces of the parts being soldered during soldering, they need to be heated to a temperature slightly higher than the melting point of the solder.
Upon contact with a part, heat is transferred from the tip to the part and the temperature of the tip drops. If the diameter of the soldering iron tip is not sufficient or the power of the heating element is small, then, having given off heat, the tip will not be able to heat up to the set temperature, and soldering will be impossible.
At best, the result will be loose and not strong soldering.
A more powerful soldering iron can solder small parts, but there is a problem of inaccessibility to the soldering point.
How, for example, can you solder a microcircuit with a leg pitch of 1.25 mm into a printed circuit board with a soldering iron tip measuring 5 mm? True, there is a way out: several turns of copper wire with a diameter of 1 mm are wound around such a sting and the end of this wire is soldered. But the bulkiness of the soldering iron makes the work practically impossible.
There is one more limitation. At high power, the soldering iron will quickly heat up the element, and many radio components do not allow heating above 70˚C and therefore the permissible soldering time is no more than 3 seconds. These are diodes, transistors, microcircuits.
The soldering iron stops heating for one of two reasons. This is a result of chafing of the power cord or burnout of the heating coil. Most often the cord frays.
Checking the serviceability of the power cord and soldering iron coil
When soldering, the power cord of the soldering iron is constantly bent, especially strongly at the point where it exits and the plug. Usually in these places, especially if the power cord is hard, it frays. This malfunction first manifests itself as insufficient heating of the soldering iron or periodic cooling of it. Eventually, the soldering iron stops heating.
Therefore, before repairing the soldering iron, you need to check the presence of supply voltage in the outlet. If there is voltage in the outlet, check the power cord. Sometimes a faulty cord can be determined by gently bending it where it exits the plug and soldering iron. If the soldering iron becomes a little warmer, then the cord is definitely faulty.
You can check the serviceability of the cord by connecting the probes of a multimeter turned on in resistance measurement mode to the pins of the plug. If the readings change when bending the cord, the cord is frayed.
If it is discovered that the cord is broken at the point where it exits the plug, then to repair the soldering iron it will be enough to cut off part of the cord along with the plug and install a collapsible one on the cord.
If the cord is frayed at the point where it exits the soldering iron handle or the multimeter connected to the pins of the plug does not show resistance when bending the cord, then you will have to disassemble the soldering iron. To gain access to the place where the spiral is connected to the cord wires, it will be enough to remove only the handle. Next, touch the multimeter probes successively to the contacts and pins of the plug. If the resistance is zero, then the spiral is broken or its contact with the cord wires is poor.
Calculation and repair of the heating winding of a soldering iron
When repairing or making your own electric soldering iron or any other heating device, you have to wind a heating winding made of nichrome wire. The initial data for calculating and selecting wire is the winding resistance of a soldering iron or heating device, which is determined based on its power and supply voltage. You can calculate what the winding resistance of a soldering iron or heating device should be using the table.
Knowing the supply voltage and measuring the resistance of any heating electrical appliance, such as a soldering iron, electric kettle, electric heater or electric iron, you can find out the power consumed by this household electrical appliance. For example, the resistance of a 1.5 kW electric kettle will be 32.2 Ohms.
Let's look at an example of how to use the table. Let's say you need to rewind a 60 W soldering iron designed for a supply voltage of 220 V. In the leftmost column of the table, select 60 W. From the top horizontal line, select 220 V. As a result of the calculation, it turns out that the resistance of the soldering iron winding, regardless of the winding material, should be equal to 806 Ohms.
If you needed to make a soldering iron from a 60 W soldering iron, designed for a voltage of 220 V, for power supply from a 36 V network, then the resistance of the new winding should already be equal to 22 Ohms. You can independently calculate the winding resistance of any electric heating device using an online calculator.
After determining the required resistance value of the soldering iron winding, the appropriate diameter of the nichrome wire is selected from the table below, based on the geometric dimensions of the winding. Nichrome wire is a chromium-nickel alloy that can withstand heating temperatures up to 1000˚C and is marked X20N80. This means that the alloy contains 20% chromium and 80% nickel.
To wind a soldering iron spiral with a resistance of 806 Ohms from the example above, you will need 5.75 meters of nichrome wire with a diameter of 0.1 mm (you need to divide 806 by 140), or 25.4 m of wire with a diameter of 0.2 mm, and so on.
I note that when heated by every 100°, the resistance of nichrome increases by 2%. Therefore, the resistance of the 806 Ohm spiral from the above example, when heated to 320˚C, will increase to 854 Ohms, which will have virtually no effect on the operation of the soldering iron.
When winding a soldering iron spiral, the turns are laid close to each other. When heated red-hot, the surface of the nichrome wire oxidizes and forms an insulating surface. If the entire length of the wire does not fit on the sleeve in one layer, then the wound layer is covered with mica and a second one is wound.
For electrical and thermal insulation of the heating element winding, the best materials are mica, fiberglass cloth and asbestos.
Asbestos has an interesting property: it can be soaked with water and it becomes soft, allows you to give it any shape, and after drying it has sufficient mechanical strength.
When insulating the winding of a soldering iron with wet asbestos, it is necessary to take into account that wet asbestos conducts electric current well and it will be possible to turn on the soldering iron into the electrical network only after the asbestos has completely dried.
Source: https://YDoma.info/tehnologii-remonta/kak-payat/kak-payat-ustroystvo-payalnika.html
