How to make a soldering iron with your own hands. Homemade soldering iron: diagram

The phrase "Soldering iron from a resistor" quite adequately correlates with the phrase "Money out of thin air". The goal is to get something out of nothing. This is not a crazy attempt to "overturn" the huge range of factory soldering irons that are on the shelves of electrical stores. However, there is so far, but not everywhere, and where there is now, it may not be later. Life is a changeable thing, especially since even the most expensive one can burn down at such an inopportune moment - so to speak, in the most interesting place. And PEV resistors (wire - enameled - moisture resistant) were, are and will be. So, it's not worth the hassle.

Here they are "two from the casket." The resistance of the left, in the past resistor, and now the heating element is 1019 Om, at a voltage of 220V it consumes 210mA and its real power is 46.2W. The resistance of the heating element of the second soldering iron is 1553 Om, at 220V the current consumption is 140mA and it will be 30.8W. It is very convenient and comfortable to use them in tandem with a power regulator. Heaters made of PEV resistors withstand a heating temperature incomparably higher than the melting point of tin. I suspect that a method has been devised to convert these resistors into heating elements at the same time they are being manufactured. This technology for manufacturing soldering irons has not received wide application among radio amateurs, and this is due to the difficulty in choosing, and even more so making suitable holders (handles) for such soldering irons. The difficulty is in the choice of material and in the design itself.

But if you manage to find something suitable for the body - the holder of the future soldering iron, then the manufacturing process comes down to elementary fixation of the voltage supply wires by twisting them with resistor contacts.

Here the case - the holder is the former connecting plug - "mother" from the three-program radio "Electronics".

And here the holder has always been it, but only in the polyethylene film welding device. Where also as a heater using a powerful PEV resistor, moreover, the product is industrially manufactured.

Resistor calculation

It is not at all necessary to determine the resistor required at face value from the very beginning by the selection method, you can roughly calculate it. It is quite acceptable to “push off” from the measurements given above. So with a soldering iron power of 30.8W, the resistance of the resistor is 1553 Om. And you need, for example, exactly 30W. We consider the method of calculating the proportion, but not direct, but inverse. Indeed, in this case, a decrease (power) is achieved by increasing (resistance).

For simplicity of possible further calculations, I propose to round the value of 1594.4 Om to 1600 Om - the calculations will still not be entirely accurate, +/- a couple of watts in terms of power.

P, W D L H d
PEV 3 14 26 28 5.5
PEV 7.5 14 35 28 5.5
PEV 10 14 41 28 5.5
PEV 15 17 45 31 8
PEV 20 17 50 31 8

A soldering iron from a PEV resistor does not need to be grounded, it will not break through to ground, the main thing is to isolate its contacts well at the junction with the power wires. Moreover, it is not necessary to use 220V for heating. For example: if you take a PEV 7.5 resistor with a resistance of 75 ohms for a soldering iron and apply 12 volts of constant voltage to it, you will get a miniature soldering iron, convenient for soldering SMD, with a current consumption of 500 mA and a heating element power of just over 7 watts. Not everyone has an electrical store near their house and not everyone lives in cities, but this is not a reason not to have the right soldering iron. He talked about the pressing, Babay.

Soldering Forum

Discuss the article HOW TO MAKE A SOLDERING IRON

radioskot.ru

RESISTOR SOLDERING IRON

I recommend to the readers of the magazine an easily calculated, easy to manufacture and very reliable electric soldering iron. For example, I have several of these at home: from a “tiny machine” for working with microelectronics to a powerful “cleaver”, with which I patch leaky metal tanks, repair well filters and other large-sized parts. Moreover, the heating element for each electrical appliance is ... a resistor of the appropriate power (type PE or PEV), powered by a household electrical network with a voltage of 220 V. Extinguishing resistances, if you can’t do without them, are reactive, more precisely, capacitive, allowing you to solve rather complex electrical problems with minimal dimensions the devices themselves.

As practice has shown, in order to carry out calculations in the manufacture of soldering irons with resistor heaters, it is enough to know Ohm's law (I \u003d U / R), the elementary power formula (P \u003d IU) and tolerably use four arithmetic steps.

Suppose that, having a PEV30 vitrified resistor with a nominal value of 100 ohms, you decided to make a soldering iron based on it for operation from a 220 V power supply. Referring to the above ratios, it is easy to determine the required data: current 2.2 A, power consumption 484 W. But…

The 30-watt parameter appearing in the name of the resistor used is the dissipation power at which the PEVZO can maintain its nominal value for a long time (thousands of hours!) without noticeably heating up. Mounted as a heater in a soldering iron (of course, with an inserted copper heat sink rod), this resistor must and can dissipate power many times greater than the nameplate one.

True, 484 W will also be unbearable for him - it will melt. Taking this into account, we will lower (for example, four times) the power per 100-ohm PEV30 by connecting a special damping resistance in series with it. Then the current that will flow through such a circuit will also decrease and become equal, according to calculations, to 0.55 A. This means that the voltage drop across the heater resistor will now be only 55 V.

But the network is 220 V. Therefore, 165 V is the proportion of damping resistance, the value of which, according to the law of electrical engineering known from the school bench, should be equal to 300 Ohms. As such a circuit element, a capacitor (for example, of the MBGCH type), designed for an operating voltage of 250-300 V, is the best fit.

We know from theory that the equivalent resistance of a 1 microfarad capacitor at a frequency of 50 Hz is approximately 3 kΩ. We need 300 ohms. Given this, we select the capacitance of the quenching capacitor 10 times larger, that is, equal to 10 microfarads.

So, the necessary data is received. Now you can proceed directly to the manufacture of the soldering iron itself.

The rod is machined (or purchased with subsequent refinement); material - red copper, diameter - with a minimum (in relation to the inner hole of the selected resistor) gap, which is recommended to be filled with silicate office glue during assembly (not shown in the figure). Although the glue impairs heat transfer from the heater, it dampens the “copper rod - nichrome spiral” system, protecting the fragile ceramic base of the vitrified resistor from cracking. In addition, the crystallized adhesive layer virtually eliminates the occurrence of backlash in the main assembly of the soldering iron.

Soldering iron based resistor:

1 - sting (copper rod), 2 - resistor, 3 - asbestos threads, 4 - electric cord, 5 - ceramic bushing, 6 - handle (plastic based on thermosetting resins), 7 - rubber bushing, 8 - metal tube body, 9 - M4 bolt (3 pcs.), 10 - insulation (lacquered cloth), 11 - metal casing.

As for the conductive wires welded to the resistor terminals, it would seem that they can simply be brought out through a hole in the tube-case. But with a high power soldering iron, it is difficult to avoid melting and burning the insulation at the cord (and there it is not far from a short circuit). Therefore, it is better to play it safe by reinforcing the insulation at the point of connection of the cores to the resistor with a heat-resistant asbestos thread (followed by impregnation with silicate glue) and installing a ceramic sleeve on the tube body. It will not be superfluous to use an additional elastic (rubber) sleeve at the input of the power cord into the soldering iron handle. Read about a homemade low-voltage soldering iron at the link.

Last tip. The power of the soldering iron can be quickly changed by adding or reducing the capacitance of the capacitors in the battery. For example, in order to quickly heat up the working rod, it is enough to connect two more of the same in parallel instead of the 10 microfarads used. The total electric capacity of the battery will then triple. As the required temperature is reached, the power can be reduced, leaving, say, 20 microfarads connected (with prolonged operation, they are limited even to the previous 10 microfarads). Moreover, if the mass of the heated rod is solid, then it happens that preference is given to a soldering iron with a quenching capacity, the real value of which is less than necessary, and only occasionally (and not for long) is a reserve connected - the entire battery of capacitors.

Perhaps the above details of the manufacture and calculation of resistor soldering irons will not seem very relevant to anyone, but I think they will be useful not only for beginner DIYers.

Noticed an error? Select it and press Ctrl+Enter to let us know.

modelist-constructor.com

:: SOLDERING IRON FROM RESISTOR::

How to make a soldering iron for small parts based on a resistor. As you know, it is more convenient to solder miniature radio components with a small-sized one, the size of a fountain pen, a soldering iron. It must be low voltage and galvanically isolated from the mains. This will protect the radio amateur from electric shock, reduce the likelihood of breakdown by static electricity, for example, insulated gate field-effect transistors. For these purposes, the proposed microsoldering iron, which can be made in just a few hours, is suitable. The power of the soldering iron reaches 15 W at a supply voltage of about 12 V, the temperature at the end of the tip is 250 ° C.

The heating element of the soldering iron is ready - it is a metal-film resistor of the MON type with a power of 2 W and a nominal resistance of 10 Ohms. The resistor is dipped in acetone or solvent for several minutes to soften the paintwork, and then carefully, trying not to damage the conductive layer, scrape off the paint with a knife. After removing the resistor leads with wire cutters, a 2.5 mm hole is drilled in the center of one of the end caps to expose the hole in the ceramic base of the resistor.

From a steel wire, a heat-shielding spring of 10 turns is wound on a rod with a diameter slightly smaller than the diameter of the resistor, and the spring is put on. the end of the resistor, in which holes were not drilled, so that 2 turns of it were on a conductive coating. The rest of the spring is stretched so that the gap between the coils is about 1 mm, and a loop is bent at the end with a diameter of approximately to connect the power conductor.

Another option for fastening the spring is also possible, which may turn out to be no less reliable. In this case, the resistor cap is sawn off with a file from the end along the edge by about three quarters of the circle, the resulting petal is bent and a hole 3 mm in diameter is drilled in it. A spring of 5 turns with a diameter of 5 mm is attached to the petal, which is wound in increments of 2 mm from soft steel wire.

The handle of a soldering iron can be, for example, a jigsaw handle with a metal ring at the end. Naturally, a homemade handle carved from hardwood is also suitable. A hole with a diameter of 5 mm is drilled along the axis of the handle for an electric cord. The protective cover is cut from sheet steel. The workpiece is bent directly on the resistor and the resistor cap is fixed in the casing with a screw and nut. To fasten the casing petals to the handle, blind holes are drilled in it and an M3 thread is cut, and then the petals are screwed with screws with such a thread. A washer is placed under one of the screws and the wire of the power cord threaded through the hole in the handle is clamped under it, the other wire of the cord is attached with a short screw and nut to the heat-shielding spring. The soldering iron tip can be made from thick copper wire. The end of the sting is inserted into the hole in the resistor housing. For a soldering iron, you can use a resistor with a lower resistance and, accordingly, reduce the supply voltage so that the power dissipated by the resistor is 10-15 watts. Suitable MLT or MT. True, the length of the MT resistor is longer than the MON, and the diameter is smaller, so you will have to change the size of the casing and tip. This homemade soldering iron is assembled in a couple of hours and does its job perfectly.

samodelnie.ru

How to make a soldering iron with your own hands

On the Internet you can find many instructions for making powerful soldering irons from improvised means. To create some products, you need good knowledge in radio engineering, but in most cases, a home-made soldering tool can be easily assembled even by a novice electrician. Next, we will just talk about how to make a soldering iron with your own hands at home, without having professional skills in working with radio engineering. 3 simple instructions will be provided to your attention, from the simplest to the most complex!

Method number 1 - Soldering iron from a resistor.

The first and simplest technology for making an electric soldering iron with your own hands is using a resistor. The device will be designed to operate at a voltage of 6 to 24 volts.

In order to make a tool yourself, you will need the following materials:

Resistor with characteristics: resistance 20 ohms, power 7 watts.

Textolite plate for making a comfortable handle.

Two copper bars of different sections. The one that is thicker is selected strictly according to the inner diameter of the resistor. The second should be thinner, for the convenience of soldering microcircuits with a small sting.

One bitten off spring ring (will serve as a retainer), a screw and a washer. You can see all accessories in the photo below.

To make a soldering iron from a resistor at home, you must follow these steps:

1. At the end of a thick copper rod, you need to drill a hole and drive the thread under the screw. It is also necessary to cut a groove for the retainer, which in our case is the spring ring.

2. From the second end, drill a hole with a diameter like a thin rod, which will act as a mini soldering iron tip.

3. All elements of the rod must be assembled into one whole, as shown in the photo.

4. The resistor is prepared for mounting the soldering iron tip, which must be inserted and fixed at the back with a screw with a washer.

5. From a textolite plate, you need to make a comfortable handle with a seat for a resistor and a wire with your own hands.

6. Connect the power cord to the heater terminals.

7. The finished homemade soldering iron is twisted and checked.

We draw your attention to the fact that with such a portable gun you can easily solder microcircuits and other radio parts.

Method number 2 - Soldering iron from a ballpoint pen.

Another unusual, but at the same time simple idea for making a soldering iron with your own hands from improvised materials. In this case, we again need a resistor, but in this case it is no longer a PEV (as in the previous version), but an MLT.

Materials and tools:

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;
Steel wire with a diameter of not more than 0.8 mm. Immediately it should be noted that the steel must take shape and at the same time not be soft, you will understand why;
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:

1. Remove a layer of paint from the surface of the resistor. If the paint is difficult to remove, connect the product to a regulated power supply and heat it up a little.

2. 2 wires come out of the barrel, cut one of them and drill a hole for a copper wire in this place (diameter 1 mm). To prevent the wire from touching the cup (this must be avoided), countersink with a thicker drill, as shown in the photo below. In addition, you need to make a small cut for the current lead directly on the resistor cup.

3. Bend the steel wire into the shape of a ring-shaped handle, with a diameter similar to that of a drank on a cup.

4. Carefully cut out the board from the double-sided PCB with your own hands, exactly the same as shown in the example in the photo.

6. It remains to install a thin sting in the 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 the back wall and the sting.

7. The last thing to do is to connect the homemade product to a 1 A power supply and a voltage of no more than 15 Volts.

That's the whole technology of creating a homemade mini soldering iron at home. As you can see, there is nothing complicated and all the materials can be found at home by dismantling the old equipment. Such a tool can be used to solder smd components on microcircuits with your own hands.

Method number 3 - Powerful impulse model.

Well, the last option is suitable for those who are already more or less familiar with radio engineering and can read the corresponding diagrams. A master class on making a homemade pulsed soldering iron will be provided following the example of this scheme.

The advantage of a more powerful tool is that the heating of the tip will occur within 5 seconds after turning on the power, while the heated rod can easily melt the tin. At the same time, it can be made from a switching power supply from a fluorescent lamp, slightly improving the board at home.

As in the 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 improvised means:

Ferrite ring from a pulse converter. The primary winding of the transformer should consist of 100, maximum 120 turns of copper wire, with a diameter of 0.5 mm. The secondary winding is represented by one turn of a copper bus, with a diameter of not more than 3.5 mm.

Copper wire, with a diameter of 1.5 to 2 mm as a sting.

All you need is to connect the tip to the secondary winding, which, in fact, is already part of it. After that, one of the ballast leads must be connected to the mains winding of the transformer, and that's all, consider that you managed to make a good fast-heating pulsed soldering iron at home!

In addition, we advise you to watch the video in our social networks. networks Vkontakte and Odnoklassniki, which show how easy it is to make a soldering iron stand at home, as well as a temperature controller and homemade soldering irons.

We still recommend using either the first or the second method, which is more understandable and easier to manufacture. As for the transformer version, although it is more powerful, it is still not so convenient to use. We hope that these photo instructions were useful for you and finally we recommend that you definitely watch all the video examples in which the assembly process is considered in more detail!

Based on materials samelectrik.ru

delaemvsjosami.ru

Quite often in amateur radio practice, it becomes necessary to solder fairly small amateur radio boards, components and microcircuits, of course you can buy a soldering station or a soldering dryer for soldering smd components, but if you have direct hands, and every radio amateur should have them, then you can assemble a miniature soldering iron made from a resistor. It is quite reliable and very easy to manufacture, as well as comfortable to use, including for soldering smd elements.

First, let's make the heating element. This role is best handled by the domestic MLT resistor with a power of 0.5 - 2 watts and a resistance of 10 ohms. An imported resistor will not work.

Carefully remove varnish and paint from the resistor with sandpaper, then bite off one of its leads with wire cutters and make a hole with a millimeter drill. We use the other output as a fastener in the handle body and for current dissipation. There is already a hole in the middle of the body of the domestic resistor and we will fix the soldering iron tip in it.

The next technological step in the manufacture of a homemade soldering iron will be countersinking the hole with a larger drill so that the tip does not come into contact with the resistor cup. In addition, a small cut is required in the anterior cup to attach the second current lead. You can make a conclusion from a spring from a metal "jack" connector, or something similar.

From a double-sided textolite, I cut out such a board, under the body of a fountain pen:

We assemble our elements into one design and solder the leads to the printed circuit board. We will make the sting from copper wire, and before installing it, it is necessary to make a gasket from mica or ceramics between the end of the sting and the cup.

To power the soldering iron, any power supply for 12 volts and with a current strength of 0.8 amperes is suitable. The technology of soldering with such a soldering iron is absolutely similar to any other.

A home-made soldering iron from a powerful PEV-10 type resistor can be assembled in just an hour without unnecessary troubles. To make a soldering iron, you need a powerful resistor, for example PEV-10. They can be found in old domestic kinescope TVs or junk dealers in the markets. To assemble a full-fledged home-made soldering iron, you just need to fasten the resistance with a handle with a clamp and insert a standard copper tip.

Powered by 220 variables through a 7 microfarad capacitor, the actual 1 kΩ resistor itself. If you install several capacitors through the multi-position switch, you can set a different temperature of the soldering tip. We drill holes in the terminals of the resistor for the M2 bolts, to which we connect the supply wires.

DIY pulse soldering iron

The purpose of the soldering iron is known even to people far from electricians. It is not at all necessary to talk about those who work in this area - for them it is simply an indispensable assistant. And the market, taking this into account, provides a huge number of devices that differ in many parameters. But not in all cases it is advisable to spend money, because you can make a full-fledged soldering iron with your own hands, without having any specific knowledge.

Homemade soldering iron

It makes sense to buy a soldering iron if you have to work with them constantly, or at least quite often. But if this is a tool that gathers dust on the shelf most of the time, then there is not much point in spending money. Moreover, it is quite possible to independently make a full-fledged apparatus of the necessary power, taking into account the likely needs.

Of course, in order to know how to make a soldering iron with your own hands, you need to understand its structure and principle of operation. After all, despite the external simplicity, there are some nuances that are preferable to know before starting work.

Structure and principle of operation

Soldering irons have an extremely simple device: a copper rod that interacts with a heating element is placed in a kind of tube that acts as a housing. A heat-resistant power cable is connected to the heater. And the whole structure is completed by a handle made of a material with low thermal conductivity.

Under the action of an electric current, a heating element (for example, a nichrome spiral) transfers thermal energy to a copper rod called a sting. The tip, having a high thermal conductivity, heats up, which allows soldering.

Knowing how the soldering iron works, it is quite possible to make it yourself. Moreover, to implement this idea in different ways, taking into account the needs in a particular situation.

Soldering iron for 220 volts on a resistor

The option with a voltage of 220 V, first of all, is good because it does not require a search for a power supply. At the same time, depending on the specific needs, its power can be made different, which allows you to create an electric soldering iron with your own hands both for soldering small equipment, and a hammer soldering iron for sealing tanks, pans and other metal utensils.

First you need to prepare parts that will be required in the process of making a soldering iron:

Depending on what work is expected to be done in the future with a soldering iron, you need to choose its power. And already on the basis of these data it is necessary to carry out calculations.

Here it is worth remembering the school physics course, and in particular the power formula and Ohm's law. To simplify the calculation, it is supposed to take a 100 ohm resistor as an example. Considering that the current will be 2.2 A, when using such a resistor, the soldering iron will consume 484 watts, which, of course, is too much. Therefore, the voltage needs to be reduced. A 300 ohm damping resistor and a 10 uF capacitor to 300 V will help in this. Thus, it will turn out to four times reduce the current, that is, to about 0.5 amperes, which will allow you to get a voltage across the resistor of 55 V.

When the necessary calculations are completed, you can go directly to solving the question of how to make a soldering iron at home, that is, to its mechanical assembly.

The main thing here is to correctly position the sting in the resistor. In order to securely fix it and reduce the gap between the copper rod and the resistor, fill it with silicate glue. This will also help protect the part from the possibility of cracking during operation.

To reinforce the insulation at the junction of wires and the heating element it is better to additionally wind asbestos thread. It would be useful to use an additional ceramic sleeve for these purposes. All this will make a homemade soldering iron safer and more reliable.

Now it remains to place the resulting structure in a suitable iron tube, on which a handle made of wood or textolite is mounted. A wire is passed into the hole of the handle as in a classic soldering iron to connect to the power supply.

Low power mini soldering iron

Quite often, the use of powerful models is inconvenient and impractical. This is especially true for work carried out during the repair of small household appliances, soldering smd and other elements sensitive to high temperatures. In such cases, a low-voltage, small, light and convenient soldering iron with a thin tip will come in handy. And here it would be useful to know how to make a mini soldering iron with your own hands, because the estimated costs in this case will be much less than in the case of buying a factory model.

As usual, it all starts with the preparation of parts and parts that will be required in the process.

Copper wire with a diameter of about 1 mm.
An unnecessary ballpoint pen that acts as a case.
A small piece of textolite measuring 30 by 10 millimeters.
A little steel wire with a diameter of 0.8 millimeters.
Since the soldering iron is made of a resistor, a 5-10 ohm resistor is used.

The first step is to prepare the resistor itself. To do this, you need to clean it from paint. You can do this in different ways: just scrape it off with a knife, connect the power and let it warm up, then remove the paint or wipe it off with a solvent. After that, one of the legs is removed, and in this place a hole is carefully drilled with a 1 mm drill, just enough for the prepared copper wire to enter. In this case, special attention should be paid to ensure that it does not touch the resistor housing. Therefore, it is worth processing the hole with a slightly larger drill - countersinking.

On the processed side of the resistor, on the cup itself, a small cut is made, where the current lead loop should subsequently lie. It is also made of steel wire, bent in such a way that a loop is obtained, which will lie in the sawn groove-propyl.

Now a piece of textolite is taken, which is cut out in such a way that one end fits well into the body of a ballpoint pen. Here, contacts are soldered on both sides, to which the supply wires will subsequently be connected. The other side of the textolite plate is made a little wider so as not to enter the pen body. Contacts are also soldered here, to which current-carrying parts from the resistor will be connected. Externally, the resulting blank resembles a kind of letter "T" approximately as in the figure:

Now all the details need to be collected. A wire with a loop is placed in the corresponding groove on the transistor, its ends are soldered to the contacts on the textolite plate.

A copper sting is inserted into the hole of the transistor. In this case, it would be useful to make protection from mica or a similar material so that during the heating of the sting, the resistor itself would not be damaged.

Wires are passed into the body from a ballpoint pen, which are soldered to the contacts on the thin side of the textolite plate - this will be the power. After that, the plate itself is also placed in the handle body.

When the base of the soldering iron is assembled from a resistor with your own hands, you should think about power. For this, a power supply with a voltage of up to 15 volts is suitable. Although it is best to use 9–12 V, this is the optimal voltage for the operation of such a device.

As you can see, with a minimum amount of materials that can easily be found in almost every home, you can make an excellent and safe homemade 12 volt soldering iron without having a high knowledge of electrical and electronics.

Autonomous battery powered device

Those who often have to work "in the field" know that the presence of an outlet where you can connect a stationary soldering iron is far from always the case. Therefore, it will be useful to have an autonomous tax in reserve. Of course, it will not work to produce soldering that requires a powerful model, but such a micro-soldering iron is still able to perform most of the work. Therefore, it is quite advisable to make a battery soldering iron with your own hands in order to simplify the work in some cases.

Almost all the parts that make up the cordless soldering iron model can be found in almost every home. Therefore, before starting work, you need to prepare:

When everything is ready, you can proceed directly to the assembly of the soldering iron. And first you need to make a heating element: a nichrome thread must be wound on a prepared copper wire with a diameter of 2 mm in the form of a spiral. In this case, the length will have to be determined empirically. So, the heating of the spiral should reach a temperature of 300 to 450 degrees Celsius.

Now you need to put a piece of a heat-resistant tube on the same wire and wind a measured nichrome thread on it. Smaller tubes are put on its ends, after which a tube of the largest diameter is put on the entire resulting structure. Now the copper wire inside can be carefully removed.

The resulting heating element remains to be placed in a piece of antenna cut off to a suitable size. A sting is also inserted here and fixed with a self-tapping screw.

In general, the whole base is already ready. It remains only to solder the wires for power to the spiral and place everything in the case.

In order to prevent fire, between the tube with the heating element and the housing it is necessary to insert a piece of some non-combustible material.

The result is a cheap, reliable and convenient tool for soldering in the field.

A soldering iron is an attribute of any radio amateur, from a professional to those who have just started. Today on sale you can find soldering irons or even soldering stations of any size. But they all have one big minus - they are quite rough and they have a large distance from the end of the sting to the edge of the handle. Such dimensions are convenient when soldering large parts, but when working with small elements, such devices are inconvenient, due to the fact that they are very heavy. position. Having looked through the schemes of miniature soldering irons on the Internet, I found that many of them have some design flaws: a non-replaceable tip, lack of grounding, and much more. So I decided to try to create more modernized“assistant” for a beginner radio amateur based on several instructions. The features of our future soldering iron include: a small distance from the end of the tip to the edge of the handle (~ 30 -40 mm), handle diameter (~ 15 mm), the ability to replace the tip and heating elements (reserve), ease of manufacture, which does not require any special knowledge.

Homemade miniature low-voltage soldering iron - drawing

As a handle, an ordinary brush was used, which was preliminarily polished and lacquered.
For a good fastening of the wires in the handle, I used such a homemade knot: I made a thread in a hollow rivet and glued it into the handle. Here you can easily fix the cable using the locking screw.
Then I moved on to the manufacture of mounts for the heat shield. They were also made from hollow rivets, but with a smaller diameter. M1.6 thread was created in them and glued into the handle holes.

The heating element was taken from an ordinary inexpensive Chinese soldering iron, after some manipulations with the dimensions, it fit perfectly with our device.

This element has a power of 7 watts and a length of 6.5 mm. Power is supplied by an adjustable power supply unit - from 0 ... 18 Volts. At the same time, the heating temperature can reach 280 degrees.
In the back of the pen was glued a regular spring, which can be borrowed from a regular ballpoint pen. This part is necessary to protect the power cable from breaking.
The ground and power wire is threaded in cambric. A socket for grounding is pressed into the main opening of the plug, which is designed for the cable, and the power cables are led out through an additional hole.
As you can see in the picture, the resulting home-made miniature low-voltage soldering iron in its dimensions barely casts from an ordinary fountain pen.

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 burned-out appliance. At such moments, one has to either borrow an instrument, or postpone the matter for an indefinite period. 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 independently assemble a small soldering iron, it is just right for small work. The manufacturing process will not take much time and effort, but you can 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 the most.

Idea #1 - Use a Resistor

The first and most simple technology for making an electric soldering iron with your own hands is using a powerful resistor. The device will be designed to operate at a voltage of 6 to 24 volts, which will allow it to be powered by various current sources, and even make a portable version powered by a car battery. In order to make your own tool, you will need the following materials:

To make a soldering iron from a resistor at home, you must follow these steps:

At the end of a thick copper rod, you need to drill a hole and drive the thread under the screw with 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 with a triangular needle file or a hacksaw.
From the second end, drill a hole with a diameter like a thin rod, which will act as a mini soldering iron tip.
All elements of the rod must be assembled into one whole, as shown in the photo.
The resistor is prepared for mounting the soldering iron tip, which must be inserted and fixed at the back with a screw with a washer.
From a textolite or plywood plate, you need to make a comfortable handle with a seat for a resistor and a wire with your own hands. To do this, use a jigsaw to cut out two identical halves of the handle and make holes and recesses for screws and nuts.
Connect the power cord to the heater terminals. It must be screwed onto the screws so that the contact is reliable.
The finished homemade soldering iron is twisted and checked.

We draw your attention to the fact that with such a portable gun you can easily solder microcircuits and even with your own hands. It can work not only from the power supply, but also from the battery. On the forums, we met a lot of reviews, where this homemade version was connected from a 12 volt cigarette lighter, it 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 will burn out. This will stop later.

Video instructions for making a simple electrical appliance

Idea number 2 - The second life of a ballpoint pen

There is another unusual, but at the same time simple idea of how to make a soldering iron with your own hands from improvised materials for soldering small parts or smd components. In this case, again, it will come in handy for us, but now it’s not PEV (as in the previous version), but MLT, with a power of 0.5 to 2 watts.

So, first you need to 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, it can be wound from an old choke or you can buy a single-core copper wire in insulation at an electrician's store and carefully remove it with a clerical knife
Steel or copper wire with a diameter of not 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 a layer of paint from the surface of the resistor. This operation can be carried out with the help of a skin, a needle file or a file, in extreme cases, a 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 supply and heat it up a little.
2 wires come out of the barrel, cut one of them and drill a hole for a copper wire in this place (diameter 1 mm). To prevent the wire from touching the cup (this must be avoided), countersink with a thicker drill, as shown in the photo below. In addition, you need to make a small cut for the wire right on the resistor cup. A triangular file will help you with this again.
Bend the steel wire into the shape of a ring-shaped handle, with a diameter similar to that of a drank on a cup. If you have copper wire, then you need to clamp the cup in it and twist it with 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 the board from the double-sided PCB with your own hands, exactly the same as shown in the example in the photo. It is not necessary to buy a new sheet of textolite. You can use a jigsaw to cut 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 with superglue. The main thing 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 the handle, which should not cause difficulties.
It remains to install a thin sting in the 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 the back wall and the sting.
The last thing to do is to 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 of 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 dismantling old equipment or looking for them in the bins.

How to make a more complex model of a mini soldering iron at home?

Video review of a device with nichrome wire, powered by 12 volts

Idea #3 - Powerful Impulse Pattern

This option is suitable for those who are already more or less familiar with radio engineering and can read the corresponding diagrams. A master class on making a homemade pulsed soldering iron will be provided following the example of this scheme:

The advantage of this tool is that the tip heats up within 5 seconds after turning on the power, while the heated rod can easily melt the tin. At the same time, it can be made from a switching power supply from a fluorescent lamp, slightly improving the board at home.

As in the 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 improvised means:

All you need is to connect the tip to the secondary winding, which, in fact, is already part of it. After that, one of the ballast leads must be connected to the primary winding of the transformer and all the elements of the circuit must be fixed in a reliable case that will protect you from accidental electric shock, since the circuit contains a life-threatening voltage of 220 volts!

The principle of operation of this design is that the ballast from the lamp creates an alternating voltage that is applied to the primary winding of the transformer and is reduced to low values, while the current increases many times over. One turn, which is, in fact, the tip of the soldering iron, acts as a resistor, on which heat is dissipated. When the button is pressed, current is supplied to the circuit, and rapid heating occurs, after the button is released, the tip cools quickly, which is very convenient, since you do not have to wait long for the tool to heat up and cool down.

Idea #4 - Simple Wire Option

There is another option for making a miniature soldering iron - using nichrome wire. For this you will need:

Manufacturing process:

Drill a hole in the bar for the copper wire 3 times larger than its diameter.
Put a piece of copper wire in it so that it protrudes about 5 cm and fix it there with thick plaster putty, let it dry.
Put on a copper bar, which is a sting, insulation and wind the required amount of nichrome wire, leaving a distance between the turns. Also put insulation on the ends and bring them closer to the handle. Then connect to twists with wires. Tape them to the handle with electrical tape.

That's all, you have another simple and reliable DIY soldering iron design.

We still recommend using either the first or the second option, which is more understandable and easier to manufacture. As for the transformer version, although it is more powerful, it is still not so convenient to use. We hope that these photo instructions were useful for you and finally we recommend that you definitely watch all the video examples in which the assembly process is considered in more detail!

Also read: