Sometimes there are situations when the owner simply cannot do without a simple soldering iron. For example, you need a multi-core cable for an outlet, or from a burnt-out appliance. At such moments, you have to either borrow a tool or postpone the matter indefinitely. After all, not everyone wants to buy an expensive soldering iron or soldering station if he is not a repairman. However, there is a simple way out of this situation - to assemble a small soldering iron yourself, it is just suitable for small work. The manufacturing process will not take much time and effort, but you will be able to save some money and gain invaluable experience. Next, we will tell you how to make a soldering iron with your own hands at home. You will be offered several designs, and you can choose the one that suits you best.
Idea No. 1 – Use a resistor
First and most simple technology making an electric soldering iron with your own hands - using a powerful resistor. The device will be designed to operate at voltages from 6 to 24 Volts, which will allow it to be powered from various current sources, and even make a portable version powered by a car battery. In order to make your own instrument, you will need the following materials:
To make your own soldering iron from a resistor at home, you must complete the following steps:
- You need to drill a hole in the end of a thick copper rod and drive the thread under the screw using a tap. It is also necessary to cut a groove for the retainer, which in our case is the spring ring. This can be done using a triangular file or a hacksaw for metal.
- From the second end, drill a hole with a diameter similar to that of a thin rod, which will act as the tip of a mini soldering iron.
- All elements of the rod must be assembled into one whole, as shown in the photo.
- The resistor is prepared for attaching the soldering iron tip, which must be inserted and secured at the back with a screw and washer.
- From a textolite or plywood plate you need to make a comfortable handle with your own hands with a seat for a resistor and wire. To do this, use a jigsaw to cut out two identical halves of the handle and make holes and recesses for screws and nuts.
- A power cord must be connected to the heater terminals. It must be screwed to ensure reliable contact.
- Ready homemade soldering iron twisted and checked.
We draw your attention to the fact that with such a portable gun you can easily solder microcircuits, even with your own hands. It can work not only from a power supply, but also from a battery. On the forums we came across many reviews where this option homemade products were connected from a 12 Volt cigarette lighter, this is also very convenient!
Please note that when first turned on, all soldering irons may smoke and stink for a while. This is normal for any model, as some elements of the paintwork fade. This will stop later.
Video instructions for making a simple electrical appliance
Idea No. 2 – Second life for a ballpoint pen
There is another unusual one, but at the same time simple idea How to make a soldering iron with your own hands from scrap materials for soldering small parts or SMD components. In this case, it will again be useful to us, but now not SEV (as in the previous version), but MLT, with a power of 0.5 to 2 Watts. 
So, first you must prepare the following materials:
- Ballpoint pen of the simplest design.
- Resistor with characteristics: resistance 10 Ohm, power 0.5 W.
- Double-sided textolite.
- Copper wire with a diameter of 1 mm, you can wind it from an old inductor or buy a single-core copper wire insulated at an electrical store and carefully remove it with a stationery knife
- Steel or copper wire with a diameter of no more than 0.8 mm.
- Wires for connecting to the network.
Making a soldering iron from a pen at home is quite simple, you just need to follow these steps:
- Remove the paint layer from the surface of the resistor. This operation can be carried out using sandpaper, a needle file or a file, in as a last resort, knife. The main thing is not to overdo it, so as not to damage the resistor. If the paint is difficult to remove, connect the product to a regulated power source and heat it up a little.
- There are 2 wires coming out of the barrel, cut one of them and drill a hole in this place for the copper wire (diameter 1 mm). To prevent the wire from coming into contact with the cup (this must be avoided), make a countersink with a thicker drill, as shown in the photo below. In addition, you need to make a small cut for the wire directly on the resistor cup. A triangular file will help you with this again.
- Bend the steel wire into the shape of a handle with a fastening in the form of a ring, with a diameter similar to that of a drink on a cup. If you have copper wire, then you need to clamp the cup in it and twist it using pliers so that the contact is reliable, but do not overdo it, otherwise you will wrinkle the body. Remember that the wire must be without varnish insulation.
- Carefully cut out a board from a double-sided PCB with your own hands, exactly the same as shown in the example in the photo. It is not necessary to buy exactly new leaf textolite. You can use a jigsaw to cut out a suitable piece from any unnecessary double-sided board. Or do without it altogether: twist the wire with wires and attach them to the handle using superglue. The main thing you need to pay attention to is that the distance between the heating element and the handle is more than 5 cm, otherwise the plastic may melt.
- Next, you need to assemble a homemade soldering iron from a handle, which should not cause any difficulties.
- All that remains is to install a thin tip in seat. To prevent the copper wire from burning through the resistor, you need to make a protective layer of a piece of mica or ceramic between back wall and sting.
- The last thing you need to do is connect the homemade product to a 1 A power supply and a voltage of no more than 15 Volts using wires.
That's the whole technology for creating a homemade mini soldering iron at home. As you can see, there is nothing complicated in making this tool, and you can easily cope with it, and all the materials can be found at home by disassembling old equipment or looking for them in bins.
How to make a more complex model of a mini soldering iron at home?
Video review of a device with nichrome wire operating on 12 Volts
Idea #3 – Powerful impulse model
This option is suitable for those who are already more or less familiar with radio engineering and know how to read the corresponding diagrams. A master class on making a homemade pulse soldering iron will be provided following the example of this diagram: 
The advantage of this tool is that the tip heats up within 5 seconds after turning on the power, and the heated rod can easily melt tin. At the same time, you can make it from a switching power supply from a fluorescent lamp, slightly improving the board at home.
As in previous examples, we will first consider the materials from which you can make a soldering iron with your own hands at home. Before assembly, you must prepare the following available tools:
All you need is to connect the tip to the secondary winding, which, in fact, is already part of it. After this, one of the ballast terminals must be connected to the primary winding of the transformer and all circuit elements must be secured in a reliable housing that will protect you from accidental damage electric shock, since the circuit contains a life-threatening voltage of 220 volts!
The operating principle of this design is that the ballast from the lamp creates AC voltage, which is supplied to the primary winding of the transformer and is reduced to low values, while the current increases many times. One turn, which is essentially the tip of the soldering iron, acts as a resistor through which heat is dissipated. When you press the button, current is supplied to the circuit, and rapid heating occurs; after the button is released, the tip quickly cools, which is very convenient, since you do not need to wait long for the instrument to heat up and cool down.
A USB soldering iron, familiar to many, is a device for soldering parts, powered by a specialized computer connector.
In addition to the device itself, the delivery set of this device includes a connecting cord one and a half meters long, as well as a small metal stand and several coils of solder rolled into a spiral.
Externally, the USB soldering iron looks like a wireless product equipped with a special connecting cord. The mini soldering iron is also equipped with a special plastic plug that protects its working tip from accidental damage.
As for the one and a half meter connecting cord, one of its ends is made in the form of a classic USB connector, and the second ends with a regular 3.5 millimeter power “Jack”.
The manufacturer organizing the supply of portable USB soldering irons to domestic market, the following performance characteristics are guaranteed:
- small dimensions and compactness of the device, which greatly facilitates its handling during the soldering process;
high speed of heating the tip (this takes no more than 15 seconds); - fairly rapid cooling of the working tip (usually 25-30 seconds is enough);
- the power consumption of the device does not exceed 8 watts;
- operating power - from a USB connector with a voltage of 5 Volts;
- the presence of a timer that automatically turns off the mobile device after a programmed period of time.
The soldering iron is turned on when you touch its body with your hand (due to the built-in touch sensor).
Finalization
The main advantages of a USB soldering iron (almost instant heating and the presence of an automatic switching mode) in practice turn into disadvantages, the elimination of which requires its modification.
These disadvantages are expressed as follows:
- severe overheating of the tip in the absence of forced cooling;
- premature switching on of the soldering iron, associated with increased sensitivity of the sensor and also leading to overheating;
- a delay in turning off the device, in some samples reaching 45 seconds, as a result of which the same overheating and failure of the device are observed.
These deviations from the norm are found in most reviews of the operation of heating devices of this class and require changes to their electronic circuit.
Based on all of the above, independent modification of a soldering USB device should be reduced to the following.
Firstly, it is necessary to slightly reduce the sensitivity of the built-in sensor, which should respond clearly when touched by hand. To do this, it is enough to solder an additional capacitor with a capacity of about 2.2 nF between the touch contact and the ground power bus.
Secondly, the delay time for turning off the soldering iron after returning to the stand should be reduced, which will eliminate dangerous overheating. For this purpose, it is necessary to reduce the value of the timing resistor connected to the NE555 timer from 200 to 47 kOhm.
Upon completion of all these modifications, working with a USB soldering iron is greatly simplified, since after reducing the sensitivity, you can control the heating of the device directly during operation. These improvements also extend the life of the heating element.
Positive reviews
Among the user reviews about the operation of the USB soldering iron, its advantages are especially noted, such as its almost pocket format, which allows you to store it directly in your work clothes.
The advantages of this device also include a high heating rate of the tip and automatic disconnection from the power line. The soldering iron fits comfortably in your hand and allows you to melt solder in any spatial position.
Individual users are not limited to just technical advantages USB soldering iron, and also note the excellent design and ease of use of the soldering device.
Particular attention is drawn to the fact that the device with USB powered It is quite mobile and can be used to repair on-board power supply systems of modern cars equipped with appropriate connectors.
Flaws
Some users attribute the disadvantages of a mini soldering iron to the insufficient power developed by the heating element.
Sometimes it is not enough to warm up the soldering zone and, especially, when working with large and thermally resistant metal products.
An analysis of user reviews showed that many radio amateurs prefer to use a USB soldering iron to work with small details and most often they connect it not to a computer, but to a separate adapter or unit.
And this is explained, first of all, by the fact that it is advisable to use the corresponding computer connector for its intended purpose, without loading it with a sufficiently powerful consumer.
This device is ideal for the initial training of young radio amateurs, since its circuit does not contain life-threatening high voltage.
In addition, after soldering, children often forget to unplug a regular electric soldering iron from the mains, which in this case is done automatically.
To summarize all that has been said, we note that in general, the soldering device with a USB connector fully complies with the characteristics stated in its technical description.
However, the greatest return from such a soldering iron can be achieved only after minor modifications to it. electrical diagram, the procedure for which was described earlier.
On the Aka Kasyan channel, one of the options for making a cordless soldering iron is discussed. A similar soldering iron in online stores costs from 15 to 50 dollars, but we can’t afford it, so it will be cheaper to make it yourself.
Watch from 1:50 minutes
A sting with a heater, how to make it, is shown in the video at the end of the publication.
Li-ion battery standard 18650, the larger the capacity, the better. Charging board for one can lithium battery with protection based on the TP4056 chip. MT3608 boost DC-DC converter module. The case is from a cheap charging 18650 battery, in which the filling of the soldering iron will be assembled. A small switch with a lock, as long as the dimensions are compact. Current is about 3 A and higher.
Where to buy radio components, etc.
You can buy a cordless soldering iron in this Chinese store. You will find the DC-DC converter there by typing in the search: MT3608 2A Max DC-DC Step. Buy a charge board by searching for: Li-Ion Professional 5V Micro USB 1A 18650.
Here is a diagram of a soldering iron. Why everything is so complicated, you will understand later.
Battery soldering iron circuit
Making a soldering iron body
At the very beginning we prepare the body. Lightly processed, removed all unnecessary. This option is convenient because the battery can be changed or replaced if necessary. The case may be different, as long as the battery fits. A pair of 20 milliliter medical syringes is perfect.
The working part of the soldering iron had to be somehow adapted. Fixed it on a terminal made of ebonite. If you work with a soldering iron continuously for ten minutes, the ebonite begins to smell slightly. But the advantage of using this button is that it has a brass bushing with a thread and no additional gadgets are needed to fix the working part.
The case is plastic and so that the ebonite retainer does not melt it, I decided to trim the front part of the case and replace it with an implant made of fiberglass. Then I glued all these parts together with Chinese epoxy resin.
DC-DC converter
Why is it needed? The fact is that the heater is designed for an operating voltage of about 9 volts. You can do without a converter. if you use 2 batteries connected in series. But in this case the costs increase, dimensions and the weight of the soldering iron. In addition, it will become problematic to charge the soldering iron from a regular USB connector.
And why the master didn’t make a heater tailored for one can of lithium-ion battery was already explained in the first video.
Let's return to the converter. Quite a popular thing. The maximum output voltage can be about 28 volts at a current of up to 2 A. But real tests have shown that it begins to boil already at inflows of 1 A. If the output rectifier diode and the microcircuit heat up ungodly, but at some point the temperature stops rising, then with the inductor In general, things are bad. After a while it starts to stink. Therefore, I decided to replace it. I had a non-working Chinese 3 A voltage stabilizer module at hand. I simply replaced one inductor with another.
Power inverter
Next, we connect the inverter to a lithium battery, or even better, to a laboratory power source. We apply a voltage of 3.8-4 volts during operation. By rotating the line resistor we achieve 9 volts of output voltage.
I did not change anything on the lithium battery charging board. The charging current is around 1 A, which is quite satisfactory. The only thing I did was replace 2 LED indicators. I used a two-color LED, which brought it to a prominent place. By the way, this board is equipped with protection that will turn off the battery when the latter is discharged below a critical level.
If you need to work for a long time field conditions, then you can take a couple of charged batteries with you and quickly replace them if necessary.
It is impossible to mix up the connection if you follow the picture above.
In addition to the charge indicator, I added an LED that lights up when the soldering iron is turned on.
Soldering iron testing
And now that the device is assembled, you can test it. The tip can heat up to a temperature of 350 degrees, but the best thing is that the inverter allows you to regulate the output voltage, and therefore the heating temperature of the tip. So, if you wish, you can output a variable resistor to comfortable spot and get a cordless soldering iron with the ability to adjust the temperature. This is one of the advantages of using an inverter.
Of the minuses. We lose 5-10 percent of power for conversion. This is a minus, given that the instrument is portable and every milliwatt in this case is expensive.
The soldering iron can be used as a USB charger for the 18650 standard - also a small bonus.
Homemade cordless soldering iron How to make a soldering iron tip
The main advantage of this mini soldering iron is that it is powered by battery voltage 3.7 V. It is not connected to the network and you can easily take it with you. Of course, its power is not great, but it is quite enough to solder wires or solder some fallen radio element.
So, what do you need to make a mini soldering iron?
- Single-core wire with a core diameter of 2 mm.
- A piece of a telescopic antenna.
- Nichrome, wire 0.2 mm. 10 cm long.
- Reinforced fiberglass cambric.
- Rechargeable battery 3.7 V.
- Battery compartment for this battery.
- A piece of round wood.
- Switch.
- Thin single-core wire 0.3-06, diameter (multi-core can be unraveled).
Making a mini soldering iron
Let's take a thick single-core wire with a cross-section of 2 mm in diameter. We will remove the insulation using a clerical knife or another method.
Then we take a telescopic antenna from any receiver, joystick or walkie-talkie and disassemble it. We need to find a tube into which our core from the wire will fit tightly. Once the antenna elbow is selected, the remaining parts can be removed.
Using a machine or manually with a file, we sharpen a thick strand of wire into a cone - this will become a soldering tip.
Cut about 1.8 cm with a hacksaw.
We cut off about 4 cm of the tube that we took from the antenna.
We take nichrome wire and measure 10 centimeters, cut off the rest.
Let's take a wire with a diameter of 1.2-1.8 mm. It is only needed for winding the coil; we will not need it later. The material doesn't matter. We wind the nichrome wire, leaving the ends about 1 centimeter.
Then take a thin strand from a copper wire, fold it in half and twist it with wire cutters.
We will pass a nichrome wire into the resulting eye and twist the end around copper wire. And let's put it aside for now.
Let's take the tube from the antenna and thread the reinforced fiberglass casing inside the tube. If you have a cambric larger diameter– you can make a longitudinal cut and adjust it to the diameter of the tube.
We take everything together and put it together.
We thread a nichrome coil with wire into the cambric so that only a 1 cm long wire sticks out from the outside. From this centimeter we make a turn around the thermal insulation. This will be a thermocouple.
We take our tip and insert it into the tube from the antenna.
On the other hand, we insert our thermoelement all the way.
Take a round piece of wood and cut off about 2-3 cm.
Drill a hole in the center for the soldering element.
We mill a groove from this hole using the same drill, see photo.
Insert the soldering tip with the thermoelement assembly. And bend the tail into the groove.
We drill more holes, but with a smaller diameter and a little further from the center.
We take a thin copper wire and make a loop on the tube and bend it. This will be the second contact.
We insert everything into a round piece of wood.
A tool such as a soldering iron is indispensable for radio amateurs, but people who are far from electronic equipment and components do not consider it an essential item. Sometimes situations happen that can only be corrected with the help of this tool, and if it is not there, then what to do? If the problem is one-time in nature, then there is no need to go to the nearest store and purchase an expensive product. You can put in a little effort and use some simple components to assemble a homemade soldering iron. There are many options for assembling this device - let's look at some of them.
Resistor device
This is a very simple but extremely reliable device. At home it can be used in different ways. Depending on the design and power, they can solder microelectronics up to laptops. The large device even allows you to seal a tank or any other large product. Let's look at how to make a soldering iron with your own hands.
The circuit is interesting in that a resistor of suitable power is used as a heater. It can be PE or PEV. The heater is powered from the household network. These damping resistances make it possible to solve problems of various scales.
We carry out calculations
Before moving on to assembly, there are some calculations you should do. So, to make devices with resistors, it is enough to remember Ohm’s law from a school physics course and the power formula.
For example, you have a suitable part of the PEVZO type with a nominal value of 100 Ohms. You are going to use it to create a tool for use in household electrical networks. Using the form you can easily calculate the parameters. So, at a current of 2.2 A, a homemade soldering iron will consume 484 W of power. That's a lot. Therefore, with the help of resistance-damping elements, it is necessary to reduce the current by four times. After this, the indicator will decrease to 0.55 A. The voltage on our resistor will be within 55 V, and in the home network - 220 V. The damping resistance value should be 300 Ohms. A capacitor for voltages up to 300 V is suitable for this element. Its capacitance should be 10 µF.
Soldering iron 220V: assembly
It is possible that the glue will slightly impair the heat transfer, but it will dampen the system of the rod and the heating coil. This will protect the ceramic base of the resistor from possible cracks.
Another layer of glue will protect against play in this important node. The wire strands will be brought out through the hole in the rod tube. This diagram will help you understand how to make a soldering iron that is reliable, efficient, inexpensive, and safe.
To avoid troubles, it is better to strengthen the insulation where the conductors will be connected to the heater. An asbestos thread is suitable for this, as well as a ceramic sleeve on the body. Additionally, you can use elastic rubber in the place where the electrical cord enters the handle.
This is how easy it is to make a soldering iron with your own hands. Its power may vary. To do this, you simply need to replace the capacitor in the circuit.
Mini soldering iron
This is another one simple circuit. This tool can be used to work with various miniature devices or parts. With it, you can easily dismantle and solder small radio components and microcontrollers. Every craftsman has the materials to create this product. You will learn how to make a soldering iron, and then you can easily assemble it from scrap materials. Power will be provided from a household transformer - any frame scan from an old TV will do. A piece of 1.5 mm copper wire is used as a tip. The 30 mm piece is simply inserted into the heating element.
Making a base tube
This will not be just a tube, but the base of the heating element. It can be rolled from copper foil. Then it is covered with a thin layer of a special electrical insulating composition. This composition is also very simple and easy to make. It is enough to mix talc and silicate glue, lubricate the tube and dry it over gas.
Making a heater
In order for our DIY soldering iron to adequately perform its functions, we need to wind a heater for it. We will do this from a piece nichrome wire. To solve the problem, take 350 mm of material with a thickness of 0.2 mm and wind it onto the prepared tube. When you wind the wire, lay the turns very tightly together. Don't forget to leave straight ends. After winding, lubricate the spiral with a mixture of talcum powder and glue and let it dry until completely baked.
We are completing the project
The third stage involves additional insulation and installation of the heater in a tin casing.
This work must be done very carefully. The ends that come out of our heater should also be treated with insulating material. In addition, use the mixture to treat any cavities that may have arisen due to lack of care.
The manufacturing process of this tool involves protecting the heater leads with heat-resistant insulating material and pulling the cord through a hole in the soldering iron handle. Screw the ends of the power wire to the heater terminals, then carefully insulate everything.
All that remains is to pack the heating element into a tin casing, and then place it evenly in place.
Now you can use this product. If you did everything correctly, you will get an excellent soldering iron, assembled with your own hands. With its help you can solder many interesting circuits.
Miniature wire-wound resistor design
This tool is suitable for small work. It is very convenient to solder various microcircuits and SMD parts. The design of the product is simple; assembly will not be difficult.
We will need an MLT type resistor from 8 to 12 ohms. The dissipation power should be up to 0.75 W. Also select a suitable case from an automatic pen, a copper wire with a cross-section of 1 mm, a piece of steel wire 0.75 mm thick, a piece of PCB, a wire with heat-resistant insulation.
Before assembling this soldering iron with your own hands, remove the paint from the resistor body.
This is easily done with a knife or liquid with acetone. Now you can safely cut off one of the resistor leads. Where the cut was made, drill a hole and then process it with a countersink. The tip will be mounted there.
At the very beginning, the hole diameter can be 1 mm. After processing it with a countersink, the tip should not come into contact with the cup. It should be located in the resistor housing. Make a special groove on the outside of the cup. It will hold a current conductor, which will also hold the heater.
Now we make the board. It will consist of three small parts.
On the wide side, connect a steel current conductor to it; in the middle part, the housing from the handle will be fixed. The second remaining resistor terminal is installed on the narrow part.
Before you start working with this tool, wrap the tip in a thin layer insulating material. So simply and easily you got a low-power 40 W mini soldering iron.
Naturally, serious and hot-air hair dryers are offered today for professionals, but these devices are very expensive and are available only to technicians from service centers for repairing computers, laptops and mobile devices. For the home handyman This equipment is not readily available due to its cost. We hope this article will tell you how to make a soldering iron with your own hands quickly and easily.
