How to measure the temperature of a soldering iron tip

Soldering iron heating temperature 40 W

How to choose a soldering iron is a task that faces almost every user who decides to solder any material. And you need to choose it correctly. Each job requires different power. In some cases, special stations are also used. We will tell you more about the subtleties of choice in the article.

Choosing a soldering iron - what parameters should you pay attention to?

review of electric soldering irons

It is clear that any tool has a number of parameters according to which it is important to select it. Accordingly, you may be wondering how to choose the right soldering iron? What are its main characteristics? To understand this issue in more detail, we decided to describe the main properties that are important to pay attention to.

• Soldering iron power and size. There are devices up to 10 W, 20 - 40 W, 60 - 100 W, 100 - 250, 250 - 500 W. And each of them is designed for certain jobs.
• Supply voltage. A popular soldering iron is 12 V, 220 V, 6 V, 36 V. It is better, of course, to take an operating voltage of 220 V. Since it is suitable for any industrial outlet. However, from a safety point of view, a 36 V device would be a suitable option. In the case when you buy a 12 volt soldering iron, you will need to additionally purchase a step-down transformer.
• Type of heating element. Today, EPSN (that is, devices with a spiral heater) are very common. They consist of a mica or ceramic tube, which is covered with wire on top. There are also devices with a ceramic heater. But they are more capricious to use and not as durable. Moreover, they are more expensive.
• Shape and durability of the tip. The sting can be made in the form of a cone, blade, needle, etc. It is best, of course, to choose a set that contains various stings. Or buy one that is most convenient for you.
• Thermal insulating handles. They are needed so that your hands don’t burn. That is, they must be properly isolated from the heating element. Usually, holes are made on the body for this purpose. The more holes, the better the thermal sink.
• Possibility of adjusting the length of the tip. As is known, with lead-tin solder the tip is “eaten up” over time. That is, dimples and notches form at the end. You can get rid of them quite simply, you just need to cut off the tip. Therefore, adjusting the tip in this case is very useful.

Also, in addition to electric ones, there are impulse and rod soldering irons. But if you select an electrical device according to these parameters, then you will not have a question - which soldering iron is better, since your tool will optimally combine everything you need for work.

Which soldering iron should you choose based on power?

review of the professional soldering iron Goot CXR-41

As already mentioned, the power of a soldering iron can vary. And it is selected depending on the type of work. To wire resistors, microcircuits, and diodes, you need devices with a power of 3-10 W. A 25 W soldering iron is suitable for repairing the radio. For household work, a 40 W soldering iron is considered good.

More powerful devices (up to 100 W) are used for wiring in car repair shops. A 150 W soldering iron is used for sealing radiators, as well as for pots and other large metal objects. A soldering iron of 200 W or more is used for soldering large objects.

A 500 W soldering iron is considered the most powerful and is often used in construction.

If you already know how to solder, then you can use a soldering station. It improves the quality of soldering many times over. And most importantly, the speed of work increases. In addition, soldering stations have other advantages.

These include: the ability to maintain a constant temperature in the tip, control of the heating temperature, the presence of a special stand and bath for cleaning the soldering iron.

The last two are especially important, since these accessories would have to be purchased for the soldering iron one way or another.

What additional tools are needed for a soldering iron?

Before starting the soldering process, it is important to prepare your work area. First of all, it must have good lighting. Therefore, take care of the lamp. It is also important to equip a table specifically for the device. Planks are placed on it where the soldering iron will be placed. Make a surface covered with asbestos. It is necessary when working with solvents or acids. Well, plus everything you need additional tools:

• Tweezers (necessary to avoid burning your fingers);
• wire cutters and insulation strippers;
• stationery knife or medical scalpel;
• file for cutting and cleaning the tip;
• thin awl;
• a syringe needle (it is important that it has a blunt end).

Source: https://steelfactoryrus.com/temperatura-nagreva-payalnika-40-vt/

Soldering iron with temperature control

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About soldering

  With proper soldering, solder (tin-lead POS-61, tin 61%): 1. shines; 2. lies smoothly and streamlined on the contact pad (CP) of the printed circuit board and the output of the part; 3. its amount and the amount of flux that has flowed out, but not evaporated, is minimal. In case of poor soldering, solder: 1.

does not shine, which indicates either that the joint has not been heated (the solder sticks), or that it has overheated, in which the flux has evaporated ahead of time (the solder is like mush); 2. lies in lumps, droplets, “swallow’s wing” - all this indicates that there is little flux and a lot of solder; 3. its quantity is large (poor dosage of solder) and dirt from flux (poor dosage of flux and no cleaning of the soldering iron tip from carbon deposits).

For proper soldering you need: 1. a soldering iron with temperature control (temperature control at about 270 °C); 2. coated tip; 3. solder with flux, with a diameter of 0.5-0.8 mm for soldering SMD parts, for the rest - 0.8 - 1.0 mm (it is better to take imported solder, for example, 63% 8PK-033); 4. tip heater - low voltage, for example, 24 V.

Remember that with an ordinary soldering iron 40 W 220 V and a glass fabric tip insulation, the current in the “tip-part-hand” circuit can amount to several mA, which can easily damage semiconductors (the human body resistance is about 1 kohm).

Therefore, to reduce the likelihood of electric shock or damage to an expensive MS: 1. reduce the supply voltage of the soldering iron using a transformer; 2. the temperature of its tip is controlled by a thermocouple and an electronic circuit; 3. use a sharp conical copper tip with a coating (the dirt will now only come from the flux, and not from the copper); 4. cleaning the tip is done periodically during soldering, wiping the tip on a piece of a special sponge (moistened in water); Proper soldering is done as follows: 1. a little fresh solder is applied to a clean tip to increase the area of ​​subsequent thermal contact at the junction; 2. The sting simultaneously touches both the output of the part and its control panel on the board, warming them up; 3. then touch the solder wire (with flux) to the desired diameter of the junction, dose the spreading solder, quickly remove the wire, and then the tip from the junction; 4. when soldering SMD components, they are first secured to the board with solder at one pin and, if necessary, adjusted;

    5. If there is an overdose of solder, it is removed from the gearbox using a braid from a shielded cable.

  An imported type SL-20 (or a similar one with similar characteristics) with a power of 48 W with a 12-16 ohm heater and a thermocouple (about 30 µV/°C) is used.
 
The soldering iron should lie horizontally, and not with the tip down (as foreign comrades do), in which the handle gets very hot. The pinout of the soldering iron connector is shown in the figure below. For correct and convenient soldering, the tip temperature should be about 270 °C, that is, always slightly higher than the melting temperature of the solder (260 °C for POS-61).
  When soldering large connectors and dismantling parts, the temperature of the tip should be much higher - about 350 °C. In this case, it is clear that the heater module and the tip darken and crackle due to high temperature. In this mode, the soldering iron will not last long. Therefore, always, as soon as you have finished this “heavy” soldering, reduce the temperature to 270 °C. In this mode, the soldering iron works all day, and the closed control unit practically does not heat up.

About the control unit

The control unit circuit is simple and easy to repeat, reliable in operation, although the design of the control unit has a small drawback - there is no soldering iron tip temperature indicator. But as practice has shown, a well-calibrated scale is quite sufficient for operation, and it is quite possible to do without a digital indicator.

Principle of operation of the device The voltage from the thermocouple of the soldering iron, at a level of tens of millivolts, is amplified by MS DA1.1, and is supplied to one input of the comparator DA1.2, and to its other input, a constant adjustable voltage is supplied from the resistive divider (temperature setter). If the temperature of the tip begins to drop, the voltage from the thermocouple will decrease, and the voltage from the amplifier output will also decrease.

And as soon as the voltage at pin 5 of the MS becomes higher than at pin 6, the comparator will switch, and the voltage at its output will become +5 V. The key transistor will open, and a current of about 2 A will flow through the soldering iron heater, and the red “Heating” LED will light up. After a few seconds, an increase in temperature will cause the opposite situation - the voltage at the output of the comparator will become 0 V, and the key will open the heater power circuit, the LED will go out.

Subsequently, the soldering iron is periodically (every half a minute) heated up, turning on for a few seconds (depending on the intensity of soldering and the ambient temperature).

Design

The power supply uses a toroidal power transformer (O 80 x 35 mm), which practically does not heat up at idle. Since the current flows through the soldering iron heater about 20% of the time, the diode bridge and transformer are installed without a radiator, and the housing is made closed. The voltage stabilizer and MOS transistor in TO-220 housings practically do not heat up. The electronic control module is assembled on a dual Op-amp, and the power supply produces voltages that are not stabilized +24 V and stabilized +5 V. All parts are mounted on a board measuring 40 x 80 mm. A printed version of the board has not been developed, and if you wish, you can do it yourself and post it here for other readers. The switch and LEDs are installed on the rear and front walls of the case, respectively. The fuse is isolated on a wire in a piece of heat-shrinkable tube. The transformer is attached with a screw to the top cover of the case, and the board is installed on 3-4 stops glued to the case and secured with self-tapping screws. The case is made of plywood 6 mm thick.

Settings

Source: http://vprl.ru/publ/tekhnologii/nachinajushhim/pajalnik_s_regulirovkoj_temperatury/9-1-0-41

DIY electric soldering iron with temperature control

05.05.2018

To perform electronic repair work, you need to have as multi-functional tools as possible. No specialist repairing laptops, computers or other equipment will use several power supplies of different capacities or a dozen different screwdrivers. A soldering iron with temperature control can replace several devices at once.

Types of soldering devices

It will not be very easy for a novice repairman to choose his first working tool. This is due to the wide variety of and workstations on the market The most important characteristics that a beginner should pay attention to when choosing a soldering iron are the power and material of the heating element. Power, in turn, has the following gradations:

• Up to 15 watts - a tool for delicate work carried out on circuit elements that are very sensitive to overheating and can fail after prolonged exposure to high temperatures. They can be powered by a battery; the heating temperature of the tip is sufficient to melt popular brands of lead-containing solders.
• From 15 to 40 watts - the most common household models, operate from a wall outlet, and are capable of quickly melting any type of solder. As a rule, they have a whole set of removable blades of different configurations for the widest range of applications. They are powered by 220 volts when connected to an outlet. The most popular devices are those with a power of 25 W.
• Range 40-80 watts - such devices are most often part of soldering stations, where there is not only a soldering iron, but also a hair dryer, which allows you to heat the parts on the board without direct contact with them. They have a built-in ability to adjust the operating temperature and air flow speed. A hair dryer and a soldering iron with a thermostat are the most versatile devices that can be used in most jobs performed by electronics repair centers.
• From 80 and above - used for soldering thick wiring, for repairing kitchen utensils (repairing pots made of aluminum and duralumin). As a rule, they are equipped with their own inverter, as they have very serious power requirements.

The material can be of two types . Strictly speaking , in both cases a ceramic rod is used, but there are significant differences in characteristics:

• Ceramic heater - high-speed heat exchange with a copper conductor makes it possible to quickly change tips depending on the current task, since cooling and heating occur very quickly. There is only one drawback - due to constant temperature changes, the ceramics may crack, and the device can be thrown away.
• A ceramic heater with a spiral wire wound over it. This design increases the strength of the heating element, but increases the time it takes for the temperature to rise and fall.

Hair dryers for electronics repair

In addition to hand-held soldering irons, air guns are widely used in performing more complex tasks With their help, you can desolder complex microcircuits and change transistors with a complex design of pin contacts. The simplicity of these operations is achieved by the fact that air soldering is non-contact and has a much larger heating area than the soldering iron tip.

Main characteristics of the devices:

• Adjustable operating temperatures of the air flow - from 100 to 300−450 degrees.
• Pump capacity is up to 120 liters per minute.
• Digital or light indication of temperature and switching status.
• Power - up to 450 watts.

Very often, hair dryers and soldering irons combine soldering stations, where both devices are powered by one inverter. In this case, a pump, two separate thermostats for temperature regulation, and one hair dryer air flow controller are combined into a common soldering station circuit. With your own hands, you can do a wider range of work using this station.

Features of infrared stations

A large subtype of repair heating tools are soldering installations, in which the heating element is infrared radiation, rather than a hot tip or heated air. Here, soldering is carried out using the radiation of an electromagnetic wave up to 8 micrometers long. These devices are well suited for reballing and replacing BGA components, removing and seating parts located in hard-to-reach places and other complex installation work in electronics repair.

Compared to convector soldering and using a soldering iron, such a device has several significant advantages:

• The radiation does not block visual control of the process, which allows operations with boards to be carried out much more accurately and without additional protective tools.
• With good insulation (for example, aluminum foil), the heat does not spread far beyond the working area, which makes it possible to protect other sensitive parts from unwanted overheating - such as transistors or capacitors, which can explode and injure a specialist with fragments.
• Radiation heats metal parts with greater force than non-metal parts. As a result, the board components intended for replacement or installation are heated to the required temperatures, and the board itself does not experience severe thermal loads. This allows you to avoid such negative consequences that can happen when soldering with a soldering iron or air, such as damage to tracks and interlayer connections of printed circuit boards.

Digital temperature controller

With your own hands, it is not at all difficult to make a device for an existing soldering iron that can change its operating temperature in accordance with the needs of the user. There are quite a few universal solutions that can be used for other household appliances. In addition to the obvious ones, such as climate control inside an aquarium or a boiler in the bathroom, some people manage to make devices that can regulate the temperature inside refrigerators.

A wide range of applications is achieved by the fact that this device is based on an electromagnetic relay, which is capable of operating from a maximum current of 30 amperes.

In addition, instead of expensive and rare parts, cheap and common ones are used, which allows you to make a simple thermostat with your own hands.

Its circuit will be built on the basis of an adjustable zener diode in a TL431 package with three terminals or its full analogue. Other parts used in the regulator:

• Electrolytic capacitors with a capacity of 2200, 1000 and 47 microfarads.
• A 5-volt stabilizer, for example, a 7805 chip and a radiator to cool it.
• Dimmer or LED for indication; it is better to look for the one that will consume the least current.
• A thermocouple, which will be based on a thermistor with a rating of 50 kilo-ohms or more.
• An electrical relay that will draw about 0.1 ampere and operate at 12 volts.
• A variable resistor with a nominal value of 150 kilo-ohms and a set of regular resistors with values ​​from 150 Ohms to 160 thousand Ohms.
• 6 rectifier diodes like BYW43, HEPR0056RT or IN4001 (4007 are also suitable).
• A bipolar transistor with an acceptor current value of up to 0.3 amperes.
• Transformer that converts 220 volts to 12.

A homemade temperature controller is usually assembled in a separate housing with a thermocouple brought outside. It is she who monitors compliance with the set temperature, turning on heating when cooling is more than one degree , and turning it off otherwise. Such a device is quite reliable and can turn an ordinary fixed-power soldering iron into a truly multifunctional device.

The advantages of use include:

• Cost-effective - soldering irons with a homemade thermostat, as a rule, can significantly reduce energy consumption.
• Durability - coupled with a good, proven brand of the main device, such a symbiosis will last much longer than the universal Chinese solutions presented in stores.
• Increased soldering quality - with the ability to control heating, good heat distribution and the absence of the need to remove the tip to avoid overheating, repairs will be carried out to a much higher quality.

Thus, when using homemade temperature control devices, you can achieve much better, faster and more economical results in complex do-it-yourself soldering iron repairs of many devices.

Security measures

To perform high-quality work on the repair or assembly of electronic components of complex devices, it is necessary to ensure the safety of the process for both the worker and the environment. Therefore, it is worth following simple rules that help to avoid injury, burns or exposure to effects on the body that have long-term consequences.

To avoid getting burns from hot metals, heated circuit boards and their components, all work should be carried out in special protective clothing. To do this, you can use cotton robes with high collars and rubber or linen gloves. The main property of protective devices should be their high resistance to fire. Goggles should be used to protect your eyes.

After completing the work, the boards must be allowed to cool and not touched immediately. The soldering iron tip also does not cool down immediately, so you should always wait for it to cool down, especially in situations where it is necessary to change it.

In order not to poison your body with the products of solder burnout when it melts, make sure that the work area has good ventilation with a well-equipped exhaust hood. Remember that heavy metals and their vapors can have very unpleasant consequences when they enter organs and tissues, which will become noticeable only after a few years.

Source: https://ObInstrumentah.info/elektricheskij-payalnik-s-regulirovkoj-temperatury-svoimi-rukami/

How to choose a soldering station?

Radio electronics for beginners

Having mastered soldering with a regular soldering iron with a copper tip, a novice electronics enthusiast thinks about purchasing more modern equipment - a soldering station.

How to choose? After all, the choice is simply amazing. I’ll tell you what criteria I used to choose a hobby-class station for myself.

If you browse online stores and read descriptions of soldering stations, you will notice that many indicate the type of heating element - ceramic . But this is not entirely correct. Oddly enough, high-quality ceramic (Japanese type Hakko-1321) and nichrome heaters (Taiwanese) also fit this description. The nichrome spiral is also sealed in ceramic, but unlike the Hakko-1321 heaters, their design and characteristics are completely different.

Nichrome heater device

A nichrome heater is made like this. A ceramic rod is taken and a spiral of high-resistance nichrome wire is wound onto it towards the end of the support rod. The winding width is about 2 cm. There is also a thermocouple pressed into the support rod - it is located at the end of the support rod. Then this entire structure is also sealed in ceramic. The result is a ceramic heater made of nichrome with a thermocouple. These usually have the inscription TAIWAN (Taiwan).

Flaws:

• It takes a few minutes to warm up;
• With intensive use, a nichrome heater burns out on average in six months. If you do not solder often, then a soldering iron with a nichrome heater can last 4 or 5 years
• Using a thermocouple as a temperature sensor reduces the accuracy of setting the tip temperature.

Nichrome heaters are found in such soldering stations as Lukey 702, Lukey 898, Lukey 852D+FAN. The advantage of these stations is that they are digital.

How are high-quality ceramic heaters made?

A high-quality ceramic heater consists of a support rod, onto which a thin layer of resistive substance and a thin-film thermistor are applied. Next, all this is baked into a ceramic shell at high temperature. The surface of the heater is smooth to the touch, and an ornate pattern is visible through the light - a thin-film layer of the heater and thermistor.

Flaws:

• Sensitive to temperature imbalance (this is when it heats up unevenly);
• When cracks form, it fails;
• Costs more than a nichrome heater (2 - 4 times);

As far as I know, high-quality Japanese heaters HAKKO 1321 are found in soldering stations Lukey 936D (I have one myself), Lukey 936+, Lukey 936D+, Lukey 852D+, Lukey 868, Lukey 853, Lukey 853D. Better check before purchasing! Read on to find out how to do this.

What's better than nichrome?

• Fast heating. I consider one of the undeniable advantages of ceramic heaters to be fast heating when turned on - a few seconds! In fact, 10 - 30 seconds and you can already solder. For those who have previously soldered only with regular EPSN, this is a shock;
• Durability. Compared to nichrome heaters, it has a longer service life;
• A precision thermistor measures the temperature of the tip more accurately;
• High power and good heat dissipation.

It is quite difficult for an ignorant person to distinguish a high-quality ceramic heater from a nichrome one. Outwardly, they look the same, since their base is ceramic.

How to determine what is in front of you: ceramics or nichrome?

The heater with a nichrome spiral has a kind of “droplet” at the end - it’s sort of rounded.

A ceramic heater has a characteristic “step” at the end. Ceramic heaters also have a built-in precision thin-film thermistor - a temperature sensor. The pattern in ceramics from the temperature sensor and heater is visible even to the naked eye. Take a look.

To be completely sure, turn on the soldering iron and evaluate the heating rate of the tip. If it takes a long time to warm up, then it is nichrome.

In my Lukey 936D I found a ceramic heater HAKKO 1321 (A1321) - there is a corresponding inscription on the heater.

Even when I was choosing it in the store, I noticed this. But on the cheaper Lukey 936A (it does not have a digital indicator), I found a nichrome heater with a drop on the end and the inscription TAIWAN (Taiwan). Therefore, I did not buy it. I really don’t like it when the soldering iron takes a long time to warm up.

not A station already has a Hakko-1321 ceramic heater, not nichrome. There is such a small difference in the name, but what a difference in price and quality.

And here is the heating element of the A-BF GS90D 90 W soldering station. It is also ceramic, with a step.

If you look closely, you can find the inscription A1329 DC and “patterns” on the case.

This soldering station looks like a regular soldering iron without a separate unit. Despite this, this soldering iron is a true temperature-controlled soldering station. True, without galvanic isolation - naturally, there is no transformer in it

Tip temperature control (thermostat)

A good soldering station has a heater with a temperature sensor and, through feedback, maintains the tip temperature set by the operator. If you pick up a soldering iron from the same Lukey 936D, you will find that the ceramic heater has 4 leads, two red ones go to the heater spiral, and two blue leads come from a thin-film thermistor.

Having measured the resistance on pairs of these terminals, I received the following data (room t0):

• Heater - 3.3 Ω (Ohm);
• Thermistor - 50~51 Ω (Ohm).

Conclusion: yes, this is real ceramics.

Obvious fakes have a heater with 2 terminals. Here is a simple soldering iron without thermal stabilization.

• In digital soldering stations, temperature control is carried out by a microcontroller. The signal from the temperature sensor in the heater is digitized and compared with the value set by the operator. The advantage of digital control is accuracy. All digital soldering stations have buttons to set the temperature. Less often - an encoder. For example, Lukey 702 has a nichrome heater, but digital control. Therefore, it has earned respect among radio amateurs.
• In analog soldering stations, a comparator is used to maintain a given temperature, for example, based on the LM358 (HA17358) chip, and a regular variable resistor is used as a temperature setter. Such stations include Lukey 936D. I took it apart personally and was convinced of this. Analog temperature control is worse, since additional error is introduced by mechanical elements (variable resistor), resistance of the temperature sensor contacts, connector contacts, and changes in the parameters of the elements. Some analog station models require calibration before use.

It is worth distinguishing between power regulation and thermal stabilization. Perhaps someone has already made a so-called soldering iron tip temperature controller. Its simplest circuits simply reduce the power supplied to the soldering iron heater and do not have temperature feedback. By reducing the power, the temperature of the tip can also be reduced.

Such attachments were used mainly for electric soldering irons with a copper tip. When idle, the tip of such a soldering iron gets very hot and burns out. To somehow reduce this effect, power adjustment was used. If you greatly reduce the power, the heat capacity of the tip may not be enough and the solder will stick. Soldering will be difficult.

Soldering irons with thermal stabilization monitor precisely the temperature of the tip (feedback). Cooled down - more power, overheated - less.

A very important parameter. First you need to imagine why you need a soldering station. You can also solder buckets :). For soldering electronic components, a 40-60W soldering station is sufficient, but it is better to have a more powerful one. For myself, in addition to Lukey 936D (heater A1321 at 50W , 24V), I also purchased A-BF GS90D (heater A1329 at 90W , 220V). I wanted to buy a 110 W model - model A-BF GS110D, but 900L tips are desirable for it, although 900M are also suitable.

As you can see, both stations have heating elements with different operating voltages. The 936 has low voltage (24V), and the A-BF GS90D has high voltage (220V). If safety comes first, then it is better to use a soldering station with a low-voltage heater. So, for example, as far as I know, previously in children's amateur radio clubs it was forbidden to use 220V soldering irons; it was only allowed to solder with low-voltage 36V ones.

Also, when repairing sensitive equipment, such as mobile phones, it is better to use a station with a low-voltage soldering iron. Here you have galvanic isolation from the electrical network through a transformer, and grounding of the tip. It will be extremely difficult to kill an element with static.

Replaceable tips

When choosing a soldering station, you should think about how accessible replacement tips are for a given soldering iron model. The most common are the 900M series tips. Here they are in the photo.

I advise you to buy at least one more tip for the soldering station. The original tip, as a rule, is not running - it is cone-shaped.

If you are not going to smoke with a soldering iron every day, then you can buy 900M copper tips. They are much cheaper, but they burn out pretty quickly. Copper dissolves in solder over time and the most that can be done with the tip is to sharpen it with a file. You can take copper tips of different profiles for testing and work with them. If someone really likes the work, then only then buy a high-quality, non-fading tip.

Anti-static electricity

You've probably already seen this inscription - ESD SAFE . An ordinary electric soldering iron has no protection against static electricity and electrical discharge. In addition, the copper rod perfectly transfers all electromagnetic surges from the electrical network to the soldered element, because a nichrome spiral is, in fact, an inductor.

In soldering stations, the essence of ESD SAFE comes down to the following. The fitting that secures the printed circuit board with the heater and the bushing that contacts the replaceable tip is grounded - connected to the third, grounding terminal of the power plug. This is not difficult to verify if you measure the resistance from the tip to the third terminal of the plug.

The trouble is that not every house has electrical wiring installed with grounding. So keep this in mind if you work with particularly tricky electronic components in the future.

The ceramic heater also acts as a protective “screen” from electromagnetic pulses. Ceramics are an excellent insulator.

Maintainability

This quality can be disputed, since now the price of hobby-level soldering stations is low and it is unlikely that anyone will repair a faulty one. But still. The main working part of soldering stations is the heating element. It can be easily changed if the original one fails. This trick will not work with ordinary soldering irons, since if the heating coil burns out, then such a soldering iron can be safely thrown away.

» Radio electronics for beginners » Current page

also be interested to know:

• Hot air soldering station.
• How to learn to solder?

Source: https://go-radio.ru/kak-vibrat-payalnyu-stantsiyu.html

60 Watt Soldering Iron with Temperature Control

The design of the soldering iron is already outdated, but it can still be used, and the temperature control makes it a good all-rounder.

Immediately after receiving the soldering iron, I was eager to try it, so the photo already shows signs of use - the metal parts are a little burnt. The handle is made of something like acrylic, fastened with self-tapping screws, it’s better not to disassemble it again.

Characteristics, selection criteria

I definitely wanted to buy something with a fireproof tip and temperature control, or just a soldering iron, or a station, but then with a hair dryer. For now I decided to buy something at the very entry level for testing, and therefore for a minimal price. The presence of gift certificates for a specific store with an expiration date weighed heavily in the choice.

Soldering iron characteristics from the seller's page:

• Supply voltage: 220-240 V, plug with flat pins, there is a separate wire with a crocodile clip for grounding.
• Power: 60 W.
• Temperature adjustment range: 200-450°C, step 25°C.
• Tip diameter: 5.4 mm.
• Dimensions, cm: 24.5 * 2.5
• Weight: 129 g.

In fact:

• The power of the soldering iron reaches 60 W only at 240 V; with my usual 210-220 V in the network, I cannot get more than 45-50 W.
• The temperature control is smooth, 25°C is the step of the marks on the regulator. Addition: but the temperature is maintained in a certain range, which may well be 50°C.
• The length is indicated without the wire outlet, in fact it is all 27 cm, the soldering iron is huge, the size of my EPSN-25. The transparent handle works like a lens, the internal elements increase in size, so the soldering iron appears much smaller in the photo.
• The complete tip is uneven in thickness; at its thickest point the diameter is 5 mm, so it does not fit tightly.

Soldering iron device

The length of the main power cable is about 1.5 m, the output from the soldering iron is well made. The thickness is normal, flexibility is above average. The ground wire is directly connected to the metal part of the soldering iron. I don’t have land, I’ll remove this wire the first time I disassemble the soldering iron, now it’s just in the way.

Judging by the four wires going to the heater, the soldering iron uses a temperature sensor, unlike soldering irons where temperature control is done by measuring the resistance of the heater. When the heating is turned on, the red LED lights up, its brightness is optimal.

Temperature adjustment

The soldering iron can only turn the heater on at full power, or turn it off completely. The temperature is kept around the set point, but fluctuates within fairly large limits. I don't have a suitable thermometer, but this effect is noticeable immediately.

When the soldering iron cools down, before turning on the heater, the set temperature often becomes insufficient, you have to increase it and wait some more time for heating.

But such an adjustment needs to be done only once, and after some experience with this soldering iron you already know in advance how to set the regulator for a specific solder and type of work, so as not to tug on it anymore.

The initial heating time depends on the temperature. The soldering iron heats up to 200 in a little less than a minute, to 300 in two minutes, to 400 in four and a half. Of course, it still depends on the ambient temperature and ventilation, as well as the network voltage.

Soldering with ordinary POS-60 type solder is comfortable when set to about 275 degrees; when working with lead-free solders, you have to increase it to about 350, for large polygons up to 375.

The values ​​here are, of course, conditional; I’m not sure that the soldering iron is well calibrated, but if you consider that not all the heat reaches the thin tip of the tip, then these values ​​look quite normal.

Sting

When I first turned it on, I set the temperature to about 250-300 degrees (according to the regulator) and tinned the tip of the tip, but it looked like it was already tinned.

I didn’t plan to use this soldering iron as my main one, so I decided not to spend money on spare tips of a more familiar shape and try to learn how to work with a thin supplied tip, for some reason they put it in every new soldering iron, maybe not everything is so bad.

Indeed, soldering small elements one contact at a time is quite possible with such a tip. When tinning the wires, I also didn’t notice any problems; you can either hook a fairly large drop of solder, or keep an even larger drop of liquid on the table.

If you need to heat a large area, then it is enough to tilt the tip to heat it with a larger tip area. Compared to working with a large and thick tip, there are both pros and cons, I think I can work with such a tip in almost any situation.

First impressions of work

The initial heating takes longer than the indicator shows. The problem is probably a long tip with a thin tip. You need to wait a couple more heating cycles until the heat arrives. A thin long tip is evil, the temperature at its end fluctuates greatly, you have to increase the temperature unnecessarily, and this leads to rapid oxidation of the solder. Only solder with solder supply, but a cheaper soldering iron without temperature control could handle this.

Working at high temperature can be very fast. When working at 400 degrees, the solder melts instantly, but so does the rosin (for example), it evaporates almost immediately upon contact with the tip. And if at a low temperature I can wipe the sting on any paper or viscose napkin, then at a high temperature the napkin begins to burn strongly.

To restore wettability to the tip of the tip, it must be tinned and the oxide layer removed. It can be removed either mechanically (special devices such as a lump of shavings, rags, napkins, etc.) and/or chemically, for example, you can wipe the heated tip with acid, but only if there is still solder on the tip, or use a special activator (a mixture of flux and solder powder). A clean or slightly oxidized tip of the sting can be tinned even with rosin.

conclusions

This soldering iron design is already outdated; now heaters are used that are inserted directly into the tip. Therefore, finding inexpensive and high-quality tips for this soldering iron is already problematic. It makes no sense to buy such a soldering iron as the main working tool.

You can find it in stores using a phrase like “60w thermocontrolled soldering iron.” 10 bucks for such a soldering iron is a lot, but it’s put together well, looks futuristic, and might be a good gift for a novice radio amateur. If you add another 5-10 bucks, the choice of soldering irons will increase significantly; if you add another ten, you can look towards entry-level soldering stations.

Quite often there are soldering irons with similar characteristics, and even with the same regulator, but in fact they do not have a temperature maintenance function. Such counterfeits heat the tip to the highest possible temperature (usually about 400°C), at which work is extremely difficult, the tip quickly burns, and the solder does not stick to it. I took this option because I saw an explicit mention in the reviews that this soldering iron maintains the set temperature, and this was confirmed.

Source: https://skubr.ru/2015/01/60w-soldering-iron-with-temperature-control.html

Soldering iron temperature stabilizer

Many people are familiar with an inexpensive soldering iron from Aliexpress with a built-in voltage regulator. A dimer is better than nothing, but it does not provide normal operation with a soldering iron. At one time, L. Elizarov from Makeevka, Donetsk region, published a diagram of a temperature stabilizer for a soldering iron without a sensor. By measuring the change in resistance of the heating element. The diagram has been published many places. There was another article in Radio magazine.

Some time ago I already used the first circuit for a soldering iron with a ceramic heater and a pistol grip. In the picture it is the top one in its already converted form.

I liked the work of the stabilizer. That soldering iron has been my main one for probably a year now. But the handle is a bit thick. It's heavier than new. Yes, and interesting.

Next, we focus on the modified diagram (Refinement of the soldering iron tip stabilizer).

Measuring the resistance of the heater with Ali (bottom in the picture) gave a result of about 450 Ohms in a cold state and about 1.5 kiloohms in a well-heated state. Those. the resistance changes three times. I decided to adapt the scheme for him too. In fact, it turned out according to the second modified scheme. R1 – 820 Ohm, R2 – trimmer 200-500 Ohm. R3 is brought out and its resistance is 470-500 Ohms. With these ratings, my soldering iron regulates the temperature somewhere from 220 to 350 degrees.

As a housing I used a regular double splitter from the store. Photo of the board and case below.

The double is disassembled using a grinder, knife, pliers, side cutters, and excess is removed from the top cover. The picture shows approximately what condition it is in.

Pay attention to the translucent film. The board began to delaminate and I removed the top layer. And it is perfect as a safety spacer between the double buses (which I connect to the board with wires by soldering) and the board. It's all inserted inside like this:

Top cover, assembly. The device is assembled.

Modification of the soldering iron itself is not difficult at all

Its essence is simple - remove the triac and connect the soldering iron wire to the heater directly. Personally, I replaced the wire (the wire with the plug will come in handy), and hung the triac by one leg on the soldering iron board. The original regulator is no longer used. I use the twister as a plug and retainer for the board.

I haven't had much practice with this soldering iron yet, but I see no reason for a negative result. The first one I converted works great and is my main one. What should you do if you decide to redo yours? Measure the resistance of the heater when cold and after warming up. Naturally in a state disconnected from the network.

• If they approximately coincide with mine, you can safely repeat them with my denominations.
• If not, then you will have to select the values ​​for R1, R2, R3.

I haven’t experimented with soldering irons with nichrome heaters, so I can’t give any recommendations.

About details

• Zener diodes of 5.6 volts with a power of at least 1 W.
• Bridges used 2 A 1000 volts. They were just available.
• Triac BT134-600. It was also just there.

Printed circuit board

Here is the signet file.

Now the main thing. Why is all this needed, what does it give? A simple current regulator does not provide stabilization in any way. If there is very little natural cooling so that the soldering iron does not overheat, then when soldering there will clearly not be enough power.

If it’s normal when soldering, then when idle there will be overheating. Inevitably.

This has a very strong impact. For example, my Chinese tips that came with the soldering iron (copper, by the way) simply melted before our eyes. It’s especially unfortunate for the flat one. With a hatchet.

In addition, if it overheats and is left idle for a long time, the tip burns and sometimes it becomes extremely difficult to tin the tip. The solder naturally oxidizes and turns into a gray-black mess. And before soldering you will have to clean the tip every time. In short, the life of the tip and the comfort of soldering are greatly reduced.

A soldering iron modified in this way acquires the features of soldering irons of a completely different price category and quality. This is actually a soldering station.

Another aspect that I checked for myself. Sometimes I solder parts with two soldering irons. Since I now have two such soldering irons, it made sense to check whether there was a potential difference between them that would be detrimental to the part being removed.  

Measurements with a voltmeter showed zeros in the range of 20 volts constant and 200 volts alternating. I turned over one of the network plugs. Perhaps it’s just high-quality ceramics in the heaters. True, it’s worth keeping in mind that in the first converted soldering iron, instead of a power supply with zener diodes, there was a Chinese small 12-volt UPS (I didn’t find powerful zener diodes then). Perhaps this is another reason.

Well, why exactly such soldering irons are especially interesting for this alteration.

In normal mode it quickly overheats. This indicates that the heater temperature is too high. And excess power. It has a ceramic heater with a fairly high resistance and a strong change in resistance when heated, which allows you to more accurately monitor the temperature.

Consequently, after the modification it will heat up very quickly, since the voltage is supplied not after the dimmer, in a reduced form, but the full mains voltage.

For the same reason, it will quickly restore the temperature after intensive heat extraction when soldering massive parts.

A little about setting up the circuit

Everything is simple here. The resistance of the chain R1, R2 and R3 determines the minimum temperature of the soldering iron. The lower the resistance, the less heating. That is, by moving the resistance slider R3 to the position of least resistance, selecting R1, R2 set the desired minimum temperature. I chose it around 200-220 degrees. But the value of resistance R3 will determine the maximum possible temperature of the soldering iron. I chose it around 500 Ohms. And I got about 360 volts at maximum.

I don't recommend choosing it too big. At some resistance, the regulator practically stops turning off the heater (the LED is on, only blinking occasionally). It's so easy to completely ruin the stings.

During normal operation, the LED shines almost continuously after switching on for several seconds. Then pauses appear, which become longer as they warm up. My soldering iron reaches operating mode in 20-30 seconds.

Trishin A.O.G. Komsomolsk-on-Amur.

November 2018

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   Discuss the article Soldering iron temperature stabilizer

Source: https://radioskot.ru/publ/stabilizator_temperatury_pajalnika/1-1-0-1408

What should the soldering iron temperature be?

When water communications consisting of plastic pipes are assembled, temperature becomes the most important parameter. It must have certain values ​​to achieve a strong and reliable connection.

Today, the technology for laying pipelines made of such materials requires compliance with a certain temperature regime, as well as specific time values, when performing welding work. If you do not follow the recommended parameters, a rupture may appear in key areas and the movement of the water flow may deteriorate significantly.

General influence of temperature during docking work

The technological process of welding polypropylene pipes is based on heating the material to the required temperature. As a result, the plastic begins to soften. When connecting parts, diffusion of polypropylene molecules occurs. In other words, molecules merge into a compound. When the material cools, an extremely strong joint is formed.

The strength of the workpieces being welded is directly dependent on the temperature regime. If the heating is insufficient, the diffusion process will not occur. The molecules of the fitting and the pipe being welded are simply not able to get into the compatible areas. The welding will be weak and will not be able to withstand heavy loads. The pair will break and the seal of the joint will be broken.

When overheated, the structure will begin to deform. As a result, the original geometry will change. A strong influx in the form of a large roller may form inside the part. As a result, the cross-sectional diameter of the pipeline at the welding site will be significantly reduced.

https://www.youtube.com/watch?v=MKZBAqnGoZ4

For normal soldering of polypropylene pipes, it is necessary to create heating to a temperature of 255-265 degrees. The heating process must take into account several parameters:

• Part diameter.
• Room temperature.
• Heating time.

Practice has shown that heating time and part diameter are directly related.

The temperature of the room in which soldering occurs also affects this process. When parts are soldered, when removing them from the “iron” or other heating device, there is a pause before the coupling begins. To compensate for cooling at low temperatures, pp pipes need to be heated a little longer. This additional time is within 2-3 seconds. The selection occurs empirically.

It must be remembered that if you heat polypropylene pipes on a heating apparatus with a temperature setting of more than 270 degrees, the top layer of the part will become very hot. The core will not receive sufficient heating. When joining parts, the thickness of the welding film will be very thin.

How to weld polypropylene pipes manually

Welding sleeves of the device are selected taking into account the diameter of the parts. They are then inserted into the welding mirror and secured well.

Contact surfaces are cleaned of dust and dirt. For cleaning, it is better to use a cleaning fluid recommended by the manufacturer of this product. The following may help with this work:

• Chlorethylene.
• Trichloroethane.
• Ethyl or Isopropyl alcohol.

A certain temperature of the device is set. Typically, the thermistor should heat up within 250 - 270 degrees. This optimal temperature allows the correct connection to be achieved.

When the thermostat reaches the desired thermal level, the heating temperature of the welding mirror is checked. For this, a special thermal probe is used.

The pipe is cut, maintaining 90 degrees relative to the axis. If necessary, you need to clean the surface and chamfer it. Stripping parameters and chamfer depth dimensions are taken from table number one. The chamfer can be removed when cleaning the part or after it, using a special calibrated tool.

Polypropylene fittings for socket welding. Grinding depth and chamfer width.

The insertion depth “L1” is marked on the surface of the pipe. Taken from Table 2. Stripping must necessarily correspond to the insertion depth.

Insertion depth L1(mm): maximum insertion depth of the heated pipe into the fitting cup.

A longitudinal mark is applied to the outer surface of the pipe and fitting being welded. It makes it possible to avoid displacement of parts during connection.

The surface of the pipe, as well as the attached fitting, must be well cleaned of oil or dirt. After achieving the required heating of the welding mirror, the pipe, together with the fitting, is installed in special sleeves. The fittings must be inserted all the way, the pipe being welded to the full stripping depth. You need to wait a little while the parts heat up.

Source: https://MyTooling.ru/instrumenty/kakaja-dolzhna-byt-temperatura-pajalnika

Soldering iron tip temperature 100 W

A soldering iron is a hand-held tool used in tinning and soldering to heat parts, flux, melt solder and bring it into the contact area of ​​the parts being soldered. The working part of the soldering iron, usually called the tip, is heated by a flame (for example, from a blowtorch) or electric current.

Soldering irons with periodic heating [edit | edit code]

• Hammer and butt-end soldering irons are a massive working tip mounted on a relatively long metal handle, the length of which ensures safe handling of the tool. To perform non-standard work, soldering irons of this type are equipped with shaped tips. These soldering irons are heated by external heat sources - mainly fire from gas or gasoline burners [1]. This is the oldest type of soldering iron, known since ancient times.
• Arc soldering iron - the soldering iron is heated by an electric arc, periodically excited between a carbon electrode placed inside the soldering iron and the tip. An arc soldering iron weighing 1 kg heats up to a temperature of 500 °C at a voltage of 24 V for 3 minutes, power consumption is 1.5-2.0 kW.

Soldering irons with constant heating [edit | edit code]

• Electric soldering irons have a built-in electric heating element that operates from the mains, from a step-down transformer or from batteries.
• Gas - soldering irons with a built-in gas burner (flammable gas is supplied from a built-in liquefied gas canister, or, less commonly, gas is supplied through a hose from an external source).
• Liquid fuel soldering irons are similar to gas ones, but heating is carried out by the flame of burning liquid fuel.
• Thermal air - in them, the parts are heated and the solder is melted by blowing them with a stream of hot air. In this way, it resembles an industrial hair dryer, but, unlike it, a thin stream of air is used.
• Infrared - heating is carried out by a source of infrared radiation.

Soldering stations [edit | edit code]

When assembling electrical appliances and electronic devices in industry and laboratory conditions, soldering stations are used, which provide additional opportunities and convenience for soldering, primarily, temperature control of the soldering iron tip with the ability to quickly set different temperature values. In addition, there are soldering stations for hot air or infrared soldering, desoldering (equipped with solder suction), with automatic solder and flux feeders, etc.

The design of a soldering iron with an internal heater is based on a miniature heating element placed in a hole drilled in the tip. Thus, it is as close as possible to the soldering point, and heat loss is minimized.

Often, a film heater on a ceramic substrate, placed in a sealed housing made of thermally conductive ceramics, is used as a heating element. The advantages of such a heater are a long service life and reliable tip insulation.

Such soldering irons are usually equipped with a temperature sensor and are used as part of soldering stations.

Rod soldering iron [edit | edit code]

The design of the most common version of an electric soldering iron in everyday life is a metal casing equipped with a plastic or wooden handle, in which a tubular heating element (heater) is placed. A replaceable, usually copper rod (“tip”) is placed inside the heater at one end, sharpened at the end protruding outward to a cone or dihedral angle. The protruding end of the tip is the working end and is tinned.

The heater is a wire made of nichrome or other alloy with high resistivity and resistance to oxidation at high temperatures wound on a ceramic or metal tube wrapped in mica sheet.

Modern soldering irons of this type sometimes use a film heater sprayed onto a ceramic tubular base, or a ceramic volumetric heater. The heater is connected to a live cord that passes through the handle and is connected to the mains or a step-down transformer.

There is a design option in which a metal core is placed inside the heating element, equipped with a threaded hole into which a replaceable tip is screwed.

Working with a soldering iron

After turning on and heating the end of the tip above the melting temperature of the solder (about 5-6 minutes), the soldering iron is ready for use.

Before soldering, flux is applied to the joint to be joined, dissolving oxide films on the surface of the parts, which ensures better wetting of the metal surface with solder.

Rosin or its alcohol solution is often used as a flux for soldering small parts made of copper and copper-based alloys, tinned steel parts. For other metals and alloys, other (active) fluxes can be used, for example, phosphoric acid or an aqueous solution of zinc chloride. After soldering using active fluxes, the soldered seam is thoroughly washed from flux residues to avoid corrosion.

When soldering electronic (for example, printed circuit boards) and electrical devices, active fluxes are not used, since even traces of unwashed flux, due to its electrical conductivity and hygroscopicity, can completely disrupt the operation of the device. When soldering these devices, non-conductive fluxes are used; the most popular are rosin or alcohol-rosin flux.

When you turn it on for the first time, a new soldering iron that has not been turned on before smokes with a characteristic burning smell, which goes away after a few minutes.

This is not a sign of a malfunction and is due to burnout of the adhesive tape or adhesive layer that was used to glue the mica sheets together during the manufacture of the heater and traces of grease on the parts of the soldering iron.

During the manufacturing process, some types of products are coated with a special paint that protects the metal casing from corrosion during storage in retail chains and warehouses. This color can be easily removed after initial heating.

The power and operating temperature of the tip of some soldering irons drop slightly over time, as surface oxidation of the heating element wire occurs, which causes a decrease in its cross-section.

To compensate for this, the diameter of the wire in the manufacture of a soldering iron is initially chosen to be slightly larger [ source not specified 2371 days ], and to maintain the desired temperature, during critical soldering, an external voltage regulator is used, for example, an autotransformer or a rheostat, or the tip is thermostatically controlled with a temperature regulator.

Source: https://vi-pole.ru/temperatura-zhala-pajalnika-100-vt.html

How to choose an electric soldering iron | Blog | DNS Club

Do you need to connect several wires together? Do you urgently need to repair a household appliance or gadget? Has the car reached its advanced age and requires constant repairs in the garage? Does your child persistently ask to buy a radio engineering set? Or maybe, due to work needs, I had to master a related field - radio electronics? Well, then it’s time to buy a soldering iron. We will look at what they are and how they differ from each other.

Types of soldering irons

There are all sorts of soldering irons - classic electric, gas, infrared, hot air, induction, pulse and many others.

There are quite a large number of people who have learned to master some of them, for example, pulse or gas models, and perform most precision work with them, including soldering planar components.

And yet, the vast majority of both engineers and ordinary people use electric soldering irons with replaceable rods in their daily work, since they are convenient, very light and relatively cheap. The vast majority of them produce two types: mica and ceramic.

Both of these types have both undoubted advantages and certain disadvantages. In the first, nichrome wire is wound onto a dielectric heat-conducting cylinder (usually made of mica, ceramics or fiberglass), into which a soldering rod is inserted. The spiral in such soldering irons is located outside, and therefore most of the heat is not used, which leads to low efficiency.

It also has a rather short resource, which, during professional work in continuous mode, leads to frequent replacement of the tool or to the need to purchase additional devices in the form of a power regulator for standby mode.

On the other hand, they are not afraid of mechanical shocks and are very cheap to produce, since their manufacturing technology has been sufficiently developed and optimized over many decades.

In the second type, a ceramic heating cylinder is inserted into a hollow tip, due to which the efficiency significantly increases and the heating time decreases; also, with careful handling, the service life of such soldering irons is an order of magnitude longer than nichrome ones.

On the other hand, these models are quite fragile, which radically changes the manner in which it is handled when working, for example, it is very risky (as is customary in mica-plastic ones) to shake off the solder from the tip by tapping.

The production technology of such models is relatively new, requires serious investments in factory equipment, and therefore they are still quite expensive and “not just everyone” can produce them.

Power

Each type of work, depending on the size of the parts and the materials used to make them, requires its own specific power. So, for soldering surface-mounted parts, you need devices with a power of 3-10 W. For soldering most radio components into printed circuit boards or mounted mounting, a 16-25 W soldering iron is suitable.

For household and electrical work, 40 W is suitable in most cases. For soldering network and automotive wires, as well as when working with parts thicker than two millimeters, a tool power of around 100 W is required. For tinning and sealing old radiators, pots and other large metal items - 150 W.

For soldering large objects, earthen polygons, thick wires, powerful chassis - 250 W. For construction work - 500 W.

The size of the soldering rod and power, as a rule, are in accordance with each other, that is, the smaller the tip, the less ability it has to accumulate thermal energy and maintain it during operation, since when it comes into contact with the soldered parts, the temperature of the soldering iron will decrease due to for heat removal.

It is worth noting that soldering irons, in addition to varying power, are available for different supply voltages. The most popular voltages are 6 V, 12 V, 36 V, 220 V. The lower the voltage, the safer the soldering iron is for humans and some radio components, however, for all voltages below 220 V, converters (transformers) are required.

Temperature

Different types of soldering work require their own temperature, which is selected in accordance with the thermal profile of the parts being soldered and the selected solder. For example, surface-mounted micro parts require heating of ~260-270°C, small radio components require about ~300°C, and large ones require about ~350°C.

Higher temperatures of ~700 - 800 °C are used in conjunction with refractory solders for soldering bronze, steel, silver, and also where the soldering area experiences significant deformation, vibration and shock.

To correctly set the temperature of the soldering iron and select the solder, you should keep in mind that during classical soldering the tip is heated up by ~40-80°C more than the parts being soldered, and those, in turn, are heated by 20-40°C more than the solder.

In order for the parts to be firmly connected to each other and the soldering to be of high quality, it is necessary that the selected solder corresponds to the soldering temperature, since underheating and overheating of the soldering iron will radically worsen the quality of the connection - in the first case, the solder will not be able to melt completely, and in the latter, the flux will evaporate before it can solder the elements.

Thus, the choice of solder must be approached consciously, since the range is quite wide, from low-melting alloys, for example, Wood's alloy (~69°C) and Rose's (~94°C) to lead-free solders with a melting point of ~400°C and more.

The heating temperature of commercially produced soldering irons mainly depends on its design and power, and the most popular models heat up to approximately ~400°C.

Tip (sting)

The tip is a very important element of the soldering iron, the basis of its high-quality work, and the first thing people pay attention to when working. The speed, reliability and convenience of soldering depend on its parameters, so you need to be extremely careful when choosing it. A high-quality tip must have good thermal conductivity, sufficient strength, protection from oxidation, durability, etc.

These requirements are often well met individually for different metals, but usually cause considerable difficulty when trying to satisfy them all at the same time. For example, a copper tip has excellent thermal conductivity, but it oxidizes very quickly, becomes covered with a layer of scale and wears out, and the more active the flux, the greater the wear.

To restore the shape and further protect such a tip, it must be periodically sharpened and then covered with a layer of solder or tinned.

The process of searching for the ideal tip is ongoing.

Thus, in an attempt to improve the characteristics of a copper tip, there is a constant search for the optimal composition of alloys or options for the arrangement of layers of different metals, when the composition of the rod differs either in length (the main part, for example, is made of copper, steel or ceramics, and the tip is made of silver, nickel or alloys copper), or by thickness (when the core is made of one material, and the coating is single-layer or multi-layered from others, which increases protection from the effects of active flux and wear). However, in this embodiment, the classical manner and technique of working with capturing a drop of solder and transferring it is difficult, so soldering is usually carried out “with feeding”, when solder with flux in the form of a wire is brought directly to the soldering point without holding it on the tip. This is very convenient for industrial production and use on a conveyor belt, and for manual soldering this method requires some skills, as well as fixation and immobility of all elements, since both hands will be busy. At the same time, such tips require very careful and careful handling, they should not be overheated or any force applied to them, they should not be exposed to abrasives (files), they should not bend bent leads of parts, in addition, their thermal conductivity is somewhat lower, therefore, solder melts less well, which, accordingly, requires an increase in temperature. Also, they should not be operated for a long time at maximum temperature, as this leads to oxidation of the working edge, which will become extremely difficult to tin. They should also not be left for a long time without solder and it is highly advisable to reduce the heating temperature during idle time. These tips are cleaned with a special damp sponge.

For various types of work, not only the material of the tip is important, but also its shape, since the convenience of work depends on it. The most versatile and popular is the wedge - a tip with excellent thermal conductivity, it is very convenient to work with, the solder accumulates on the tip, and you can solder either with wire solder or with lump solder.

With such a tip you can solder both small parts and rows of pins of modern microcircuits, for which a tip or edge is best suited and they also remove random jumpers, as well as large parts, for which the wide side of the wedge is more suitable. Cones with a plane cut at different angles are also popular and have similar qualities.

Soldering irons and stations produced in Southeast Asia most often come with wedge-shaped tips, which are convenient for soldering small parts. Other external options, such as: needle, fork, microwave, knife, nozzle for soldering plastics, hatchet and others, are usually the province of professional technologies, where their use greatly facilitates, reduces the cost and speeds up the soldering process.

However, despite this variety, choosing the best shape or material from which the tip is made is more a matter of personal preference and skill.

Criterias of choice

Source: https://club.dns-shop.ru/post/16289

Why know the temperature of the soldering iron

There is no universal soldering iron and soldering temperature that is suitable for absolutely all cases. Much depends on the solder, on what materials the master works with, as well as on the goals he pursues.

And in general, choosing the optimal temperature is not such a simple matter. Typically, the soldering iron tip is heated until it begins to melt the solder. But in some cases more fine tuning is required.

A few soldering rules

There is one unshakable rule: the temperature of the soldering iron must be higher than the melting temperature of the solder.

Moreover, the solder material must be completely melted before it fills the empty spaces and is evenly distributed over the surface.

If the soldering iron tip is too overheated, the solder will oxidize and the soldering seam will not be of very high quality. By the way, oxides can appear on the soldering iron itself, and in order to get rid of them, experts advise purchasing a so-called tip activator - a really very useful thing.

And if the soldering iron tip is not just overheated, but burns out, then the solder material will no longer stick to it at all. “Cold” soldering (that is, when the temperature of the soldering iron tip is less than optimal) will also not give the expected result.

If the solder material does not melt to a fluid state, the soldering area becomes dull and rough, and the connection is not very strong.

And one more important rule, suitable for any soldering: the temperature of the elements being soldered must certainly be the same.

Types of solders

The variety of solders is divided into two categories:

• refractory;
• fusible (soft).

The soft category includes solders that have a melting point of up to 400 ℃ and relatively low mechanical strength (tear resistance up to seven kilograms per square millimeter). They can be melted with a soldering iron.

The marking of such solder always contains the abbreviation POS and numbers indicating a specific percentage of tin. As an example, it is worth citing the very common solder material POS-61, the operating temperature of which is from 190 to 260° Celsius.

POS-61 and other soft tin-lead solders are, in particular, used in radio installation. In general, when working with printed circuit boards, you must act extremely carefully.

It is better to avoid sudden heating and temperature increases, and the duration of exposure to the soldering iron should not exceed more than two seconds. This is especially true for objects such as integrated circuits and field-effect transistors.

To obtain special properties, bismuth, cadmium, antimony and other metals can be added to the composition of tin-lead solders. Low-melting solders are produced in the form of cast rods, pastes, wires, powders, tapes, as well as tubes with a diameter of 1 to 5 millimeters with rosin inside.

Among the trusted manufacturers of such solders, it is worth highlighting the brands Felder and AIM.

And one more addition: experts recommend not using metal boxes, lids, or cans for storing solders. Solders can stick to the metal - as a result, a rosin mess appears on the walls, which will not be very comfortable to work with.

Brazing alloys are characterized by the fact that they create high-strength seams. In radio installation work they are used much less frequently than fusible ones. Moreover, two subgroups of hard solders can be distinguished - copper-zinc and silver.

The former are used for soldering bronze, steel, brass and other metals with a high melting point. Interestingly, their color depends on the percentage of zinc content. And the melting temperature of, say, PMC-42 solder is 830 ℃.

Silver solders are perhaps even more durable. They are used mainly for soldering copper-brass and silver products. The melting temperature of such solders is in the range from 720 to 830 ℃. When working with such materials, a torch is used.

Melting various materials

The craftsman may well need to solder copper - for example, we are talking about heating pipes or other products made from this non-ferrous metal.

You can work with a soldering iron with copper and its various alloys using different solders, both soft and hard. At the same time, the temperature of soldering copper elements with soft solders is 250-300 ℃, and with hard solders – 700-900 ℃.

What should be the temperature of the soldering iron tip if you need to solder, say, polypropylene products? In this case, the optimal temperature will be +260 ℃, and the conditional permissible range is from +255 to +280 ℃.

But it is worth noting that if you overheat the soldering iron above 271 ℃ and reduce the heating time of the tool, the surface of the soldering zone will warm up much more than the inside. This means that the resulting sealing film will be very thin.

Useful measuring devices

Practice shows that if the temperature of the tip of the soldering iron used is selected correctly, then, when it cools down, the soldering area will have a characteristic mirror shine.

Conversely, the porosity and dullness of the soldering area indicates that the procedure was not carried out very well.

It is quite possible to find out the optimal melting temperature experimentally. This requires special soldering iron heating regulators (laboratory transformers). There is, however, an easier way to regulate the temperature - change the length of the tip.

But this method is perhaps only relevant for homemade soldering devices. In any case, the master has the opportunity to find out in advance at what temperature or at what length of the tip the solder appears to have a mirror shine.

Armed with this knowledge, you can begin real responsible work.

If you have the financial means, it is worth purchasing a special thermometer (sensor) for a soldering iron, which measures and calibrates the operating temperature of the tool.

There are quite a lot of such sensors now. And it will not be difficult for anyone who wants to purchase the desired model online or offline. They quickly and accurately measure the temperature of a soldering iron tip using a thermocouple (thermoelectric converter).

When choosing such a thermometer, you should pay attention to such characteristics as resolution, measurement range (for example, it can be from 0 to 700 ℃), accuracy, dimensions, and possible power sources.

However, simply measuring the temperature is not enough. It is important that the soldering iron keeps it unchanged during possible power surges in the network - that is, a special stabilizer is needed.

You can make such a device yourself - there are quite simple diagrams available in the public domain. In addition, there are now soldering irons and soldering stations with a built-in stabilizer.

And many professional soldering stations allow you to accurately set the temperature and desired soldering mode by simply pressing buttons or flipping a toggle switch. This greatly simplifies the work process and allows you to always be sure of a good result.

Source: https://svaring.com/soldering/praktika/temperatura-pajalnika