How to replace the mica in the heating element. Heating element for the soldering iron do it yourself
I decided to rewind the burned 40-watt soldering iron. Why not, if all the materials are there?
But rewinding by 220 V. Burned at the first inclusion from the released Gary at a voltage of 150 V. Since when rewind used a sticky ribbon from fiberglass. Therefore, it is necessary to apply insulating materials pure from combustible substances or to zero.
And first include under reduced stresses up to 220 V. As the smoke stops. For example, for soldering iron 40W. through light bulbs 15,25,40W.
Torture again, winding a 220V winding with a thin wire. I was breaking.
He took a nichrome from the hair dryer and wound two layers. It turned out on 30B., 1,1A.
Then I had an electronic transformer for 12V, which may have come true
To power the soldering iron in one layer, but the soldering iron was already ready.
Basic materials for rewinding:
Mica. Taken from a mica capacitor of large-sized type KSO13.
Nichrome. From hair dryer.
A lowering transformer and graphite rod from a battery welding with copper wire.
Asbestos cord for thermal insulation.
Awhericheart black. Withstand temperatures up to 300 degrees.
Metal strip. For small soldering supplies, it can be forged from connecting hoses for toilet bowls, boilers, ... but it is very soft, maybe in two layers.
For 40W. Better than a feet. From high pressure hoses, brake hoses, etc.
MHTF wire. To rewind the transformer and for the soldering iron, used with an outer diameter of 0.7 mm insulation. For welding to the nichrome of two segments of the wire with a diameter in isolation 2mm.
We voluntarize a mica seat winding and fix it with several turns of thin thread.
Before winding, weld one segment with nichrome (who has no experience - read on the Internet, then practice), insulating the spin and insert the handle into the tube. The first turn is fixed, winding two turns on it. Do not forget that after the inserted conclusions you need a place to attach an outdoor strip, about 1 cm. And from the end the same. The last turn is fixed, winding it several times with a subtle nichrome. We bring into the handle the second segment of the thick wire, we twist with nichrome, weld, are insulated. The conclusions of the sections of the wires from the handle must be well fixed to accidentally do not pull the coils. At least to insert the wood on the glue into the handle.
Now you can connect to a downstream transformer or to the power supply unit with adjustable output voltage to check the normal operation of the heating winding and the approximate determination of the voltage and the current at which it will work.
After cooling, we wind the mica layer then asbestos cord. The cord in contrast to the leaf will not crumble and lies more. Who confuses asbestos, he can search for a replacement. Some fiberglass cord or matter.
Check that the strut puller will turn on the cord. Lubricate auto-service and wear a fever. The same nichrome is typing the edge of the pens from the side of the handle, after which we stretch, we are tightened and tighten the front of the front. We are brushed and cutting with nipples unnecessary part of the patch. While the sealant is frozen, we collect soft, not melting from the sore tag, cord. Since there was a wire in fluoroplastic insulation with an insulation diameter of approximately 0.7 mm, it used it. He took 6 wires, splash their pigtail - it turned out a soft strong cable. It is soldered to the conclusions from the soldering iron, and the spah attach the tape to the handle. This makes it easy to overpass the cable if it trigs the handle.
Light and small-sized electronic transformers for halogen lamps gave rise to apply them to power low-voltage solders.
I got on 160W. With 100-ampered transistors 13009, since such power is superfluous, they replaced them with an existing 4-ampere 13005. Instead of 8 turns of the bus for 12V., Mottled 45 turns with a tap from 39. The set switch connects the soldering iron
To 39 turns - for soldering the little things without overheating or 45 turns. The output transformer is installed on the board on silicone with a gap to the board of about 1mm. If necessary, unnecessary turns are easily removed. If the soldier's power switch will be installed inside the housing, it is possible to install a transformer, shifting one way. The LED indicator with a diode and a resistor installed in the center of the output. transformer by connecting it to the last turns.
The network plug can be attached to the housing, cutting it off from such devices, for example, from wall-mounted power supplies, charging for cellular. You can also attach a plug on a short cable, it is more convenient to connect to tees.
When you first turn on the electronic transformer has not earned. Mala load. Since the load is constant and to. H It is not foreseen that without bothering the alteration on the OS voltage, added the turn to the current overlook the current winding on a small ring, and he earned.
What is written here this general direction. Everyone will have their own way depending on the components available.
Press machine is installed on a wooden base 8.
Notes: 1. With any processing of plastics and especially after their cutting (drilling, turning, etc.), it is necessary to make residual stresses in water (more than an hour). Otherwise, the item can crack in the processing places
and split.
2. When used as a raw material from Capron, nylon, etc. It is necessary to remove all seams, cut the sock and heel, because
they are made from other materials.
3. When using kapron tissues, it is impossible to use those in which the base is made of cotton or other threads.
To obtain various decorative edging, you need to make movies 9 The desired configuration. The filler is screwed to the spine. When extriving, the mass acquires the profile of the filler hole; Upon exit from the die, the mass must be cooled in
cold water.
It should be noted that with the help of this press machine (using the fillers), it is possible to make insulating gaskets from polychlorvinyl (insulating edging for metal-raised television tubes, etc.). The softening temperature of the polychlorvinyl 80-100 ° C; When using other materials that are not specified here, it is necessary to use the details of the softening to determine the softening temperature, remembering that the temperature of the softening began there.
Mica. The mica is a non-combustible, layered mineral with high dielectric parameters.
There are two varieties of natural mica: Musca
cNT-with high electrical data and flogopit-with reduced electrical data. The first is used mainly in radio engineering, the second-in electrical engineering.
A number of materials, the basis of which serves as a mica, are also used as thermo - and electrical insulating materials. Spirling mica-micanitic dust - serves in refractory smear filler.
The types of mica and some materials based on it are shown in Table. twenty.
Table 20.
The most commonly encountered the following mica brands:
S-mica exemplary (muscat);
SF mica filter (muscat);
SNC-mica low frequency (muscat);
Microwave mica high frequency (muscat);
SZ - mica protective (muswit and solid flogopit).
Note. In the manufacture and repair of various equipment, and especially soldering iron, sometimes it is necessary to bend the mica with small bend radius. So that at the same time the mica does not crumble and did not break, it must be pre-rolled to light yellow. The mica becomes more elastic and bends, not cracking and not breaking.
Rubber. Rubber is an elastic insulating material with low electrical data. The usual rubber, which manufactured industry produces, has three varieties: soft, medium hardness and solid. In addition to the instructions of hardness, sometimes there are letters in rubber: a-malnobhet in gasoline;
B - swelling in gasoline. Most shock absorbers and depreciation gaskets of radio amortizers
out of rubber, although recently some plastics began to apply for these purposes.
Soft leaf rubber is on the manufacture of PAS-Sikov for amateur tape recorders.
Microporous rubber is used for various sound-absorbing coatings (for example, when creating high-quality audio units).
Paper. Paper - the cheapest insulating material, has low electrical data, but after appropriate processing (impregnation) can compete with the best insulating materials. It is used mainly in the manufacture of permanent capacitors and transformer windings.
Cardboard is on the manufacture of insulating gaskets, frames of transformers coils, etc.
Some papers and cardboard data are given in Table. 21.
Table 21.
Fabrics. Widely used for decorative finishes of finished equipment. In combination with insulating varnishes and resins, some insulating materials are the basis.
The data of some tissue products are given in Table. 22. Table 22.
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Glass. The main material for various scales, protective glasses of instruments, manufacture of optics, mirrors, etc. serves glass. The main types of glass processing are cutting, drilling and gluing.
Cutting glass with a diamond or glass cutter is simple and does not require a special explanation. But sometimes there is a need to cut the glass of a complex configuration. For this, the glass is applied to the glass pattern, but so that one side of this picture occurred to the edge of the workpiece. "At this place, they make the triggered personal file. Redesome acute subject (instrument for burning wood with a full potassium or soldering iron for soldering solid soldering described in one of the following sections) Slowly drew a drawn outline. Under the hotstone, a crack will be continuously formed, noticeable with the naked eye. Next glass has small areas (better in water). The finished item is boiled in water for an hour.
At the request of the edge, you can cut a small abrasive bar.
Holes in the t e. Holes in glass can be done in one of the following methods.
1st way. The hole in the glass is drilled by the usual drill without a large pressure. Glass should lie on a solid and smooth surface. Drilling to produce only through the conductor (piece of metallic sheet 5-8 mM. With a hole equal to the diameter of the thickness of the drill), tightly pressed to the glass.
When drilling the place of the future holes to continuously make the following composition (in weight parts):
Camphor - 8;
turpentine - 12;
2nd way. Drilling is made by flat drill (sharpened spatula) also via conductor. The drill must rotate alternately in one, then in
other side.
Emulsion in this case serves silicate glue (liquid glass); Emulsion changes every time she clings.
3rd SP-Pers. The drill can be suitable for the diameter of the copper (worse than brass) tube; conductor
here also needed.
There are several drops of silicate adhesive with emery powder to the place of the future hole.
she Corundum № 000-240); When drilling, this mixture is continuously updated.
Holes in relatively thick glass (more than 4 mM.) The copper tube is drilled slightly extended at the end (kerner or other suitable tool), which facilitates the drilling process at the final stage and reduces the likelihood of glass damage.
The gluing of optical glass.
The optical glass is glued with special high transparency adhesives, such as fir balsam and balm.
The glass in front of the gluing is carefully deguted with dichloroethane or acetone and wipe the clean suede. The glue is applied on both bonded parts, after which they are clamping into a clamp. It should be monitored so that there are no air bubbles in the place of gluing.
On other materials, the glass is glued with various adhesives, cements and smears, the recipes of which are shown below,
IV. Adhesives, pastes, putts, varnishes. Diluents.
Adhesives are widely used in amateur practice. The use of appropriate glue in combination with properly sustained technology allows you to simply and reliably connect the metal with glass, rubber, glue the plastic, porcelain and much more. Below are the most common adhesives.
Starchy Cleeter - This paper glue; his
starch - 60-80 g / l;
bura - 25 g / l.
The starch is dissolved in * / 5 parts of the water (cold), thoroughly stirred, brewed with the rest of the water (steep boiling water) and, finally, are injected into the hubbur. Cleaster from flour-This glue for paper and cardboard;
its composition:
Flour - 200 g / l;
clay joiner (dry) - 50 g / l
The flour is mixed with cold water to a tough condition and poured with hot joinery glue (temperature 80 ° C). Glue be sure to strain.
Binding glue. VAO is added to the divorced hot joinery (right in the water bath) part (from total glue) glycerin.
Gumiarabic-Glue For paper and cardboard manufactured of Comedy (frozen juice) of some fruit
Wheat flour is mixed with cold water before the formation of liquid dough. In the rest of the water (heated to 50 ° C) dissolve aluminum alums; In the resulting solution, the dough is placed and boiled before the formation of a transparent syrupid mass.
Dextful glue - Common paper glue. The preparation recipe is simple: dextrin at the rate of 400 g / l bred with cold water.
Glue for cardboard. At 100 V. h. Water dissolve 9 V. h. Office (silicate) glue, 6 V. h. Potato flour and 1 c. h. sugar. The resulting cleaner must be heated to the preparation of monotonous mass.
Fotocols. Photocleucy composition:
starch - 60 g / l;
aluminum alum aluminum - 40 g / l;
chalk (dental powder) - 40 g / l;
sink dry - 1 g / l.
Starch poured 10 V. h. Warm water, stirred and plot 30 V. h. steep boiling water. Separately dissolve the alum in the warm (remaining) water, the solution is poured into a honesty and spin well. After half an hour, the holester chalk (dental powder and blue) is added and stirred thoroughly.
Glue stored in a closed glassware. Adhesive for sticking fabric, dermatitin and leather on wood. The composition of glue is given in weights:
wheat flour - 40;
rosin - 3;
aluminum alum aluminum- 1.5;
All dry components are mixed, poured with water and stirred. The resulting tough mass is put on a weak fire and stirred until the mass starts thick.
Bonding to produce hot glue.
Casein glue. Blesses paper, wood, fabric. Skin and ceramics. Casein (powder) is diluted in cold water at the rate of 250 g / l, pouring water with small portions and continuously stirring the adhesive mass.
Glue composition:
carpentry glue - 200 g / l;
sugar -200 g / l;
lime harated - 70 g.(l.
Dissolve sugar in water, then lime and heated on slow heat until a transparent liquid is obtained. The resulting solution is filtered off and lowered dry joinery in it. Within 24. hour Carbonate glue swells, and the venture is dismissed in the melting.
In a closed glassware, glue can be stored for a long time and does not lose gluing ability.
Glue for glass. The gelatin is dissolved in an equal amount (by weight) of a 5% solution of potassium two-axis (the solution is prepared in a darkened room). The resulting glue insoluble in hot water. Details are missing, tighten the clamp (or firmly wrapped with threads) and put on 5 ^ -8 hour on light.
Glues for glass and ceramics.
1. Casein dissolved in liquid glass (silicate adhesive) of the consistency of sour cream.
2. Gypsum, mixed on egg protein to consistency sour cream.
3. Gypsum, clumsy for a day. A saturated solution of aluminum alum. After soaking, the gypsum is dried, grind and kneaded on the water to the consistency of sour cream. Such glue is well glued ceramics.
4. Dry small small chalk (dental powder), diluted in liquid glass in the ratio of g: 4.
Universal cement. It is used in unnothessment; called "cement phosphate"; He perfectly glues ceramics, is not afraid of hot water.
Cement is divorced as follows. The desired amount of cement (powder) is poured into the glass dishes and poured a diluent. Everyone is thoroughly mixed with a glass stick and immediately applied for preventive parts. Details must be pulled by clamp (or thread). Drying time 2. hour.
Glues for the skin.
1. Glue "Rapid"; Its composition (in weight parts):
celluloid -15;
acetone - 65;
solvent of RDV (or № 000) -20.
2. Natural rubber solution (1-2 c.) In the servo carbon (10th century) with the addition of a small amount of turpentine.
5 L.. A. Yrelykni 65.
3. Roasting glue (bone) with the addition of Tanina to it before the formation of the stretching threads. Glues rubber.
1. Natural rubber (1, h.), Dissolved in a solvent gasoline (Goloshin gasoline) or in aviation gasoline B-15 V. h.).
2. High quality rubber glue; Its composition is given in weight parts):
seroublerod - 10;
guttapercha - 1.3;
graphite - 10;
luck number 000 - 9.
Rubrax and bitumen number 3 melted and the remaining components are mixed up to them. The wrapper obtained is thoroughly mixed. Details glue hot smelting.
Craise Mask Consists of the following components (in weight parts):
rubrax - 2;
varnish number 000 - 2.5.
Rubrax is melted at a temperature of 120 ° SIV it add chalk and varnish. Everyone is thoroughly mixed. Glue hot smear.
Paste for gluing glass with metal. This paste is quite firmly bonded glass with metal. Liquid consistency paste allows you to glue the large surfaces of the specified materials.
The composition of the paste (in the weights):
copper oxide - - 2;
emery powder No. 60-2;
liquid glass - 6.
All components are tricious before the formation of a homogeneous paste. The glued parts are heated to 100 ° C and kept at this temperature 2 hour, Then cooled to room temperature. After 12-14 hour Pasta fully solidifies.
Masking "Glass - Metal". This type of smear is distinguished by an increased hardness of the glued seam that can carry average mechanical loads.
Below are two cassette recipes (in weight parts).
1st recipe:
glove lead - 2.5;
rosin - 3.5.
Carefully grind and dried components mix and breed with genuine olifa to lolluages \u200b\u200bthickness.
2nd recipe:
glove lead - 7;
marganese boron-acid- 1;
rosin - 20.
Everything is grinding, dry and mixed with genuine oils to lolluages.
Pasta to cover the glazed resistance.
When repairing grooved resistance and especially when the device, it is necessary to restore the resistance coating, otherwise the resistance life is sharply reduced. You can restore the impaired resistance coating with a special paste (the recipe of which is driven below).
The dry talc (6th century) is mixed with liquid glass (silicate adhesive), which take so much to obtain a mass of consistency of sour cream (approximately 8-12 centuries).
Damaged areas of the coating are wetted and dried at room temperature for about an hour. The resistance is then heated to 100-110 ° C and kept at this temperature 10-15 min.
Magnesite putty. This magazine is used when gluing ceramic products and metal with ceramic details. The glued seam withstands heavy loads.
magnesium -4 oxide;
porcelain flour - 2;
magnesium chloride solution (Ud. Weight 1.25) - 5.
Magnesium oxide is calcined for an hour at 400-500 ° C. Porcelain flour is dried for 30 min. At a temperature of 100-120 ° C. Magnesium chloride is dissolved in water at the rate of two parts of magnesium chloride per part of the water.
After that, magnesium oxide and porcelain flour are stirred, the resulting mixture is poured with a solution of magnesium chloride and is mixed to obtain a homogeneous mass.
Masset apply immediately after making. Time of complete drying - two days.
Note. Porcelain flour can be obtained if you split the slices of an old (bat) porcelain dishes and cool them in water, repeating this process several times.
Glutglicin gaze. This putty (for use and in the quality of the seam) is similar to magnesite and is widely used in the industry for connecting ceramic parts between themselves and with metals.
The composition of the smelting (in weight parts):
technical glycerin -1;
glove lead - 8.
Glip dried for 2 hour At a temperature of 230-250 ° C, it is triturated in a mortar and small doses (with stirring) poured glycerin to it. Mazazka use immediately after manufacture. Drying time of putty-one day.
Note. Glove lead can be prepared from lead turbine. For this 100 g. Dry lead suit must be taken 1 g of gas soot, mix everything thoroughly and rolled at a temperature of 450-550 ° C for an hour.
Melting for lubing cracks in iron and cast-iron castings.
Magnification composition (in kg):
iron sawdust - 1 ammonia - 0.02 Haired lime - 0.1 Liquid glass - 0.1.
Dry components are mixed, poured with liquid glass and stirred thoroughly before formation
uniform mass. Masset apply immediately after making.
Melt to strengthen iron fittings in stone.
The composition of the smelting (in d):
iron sawdust - 100;
vasharyar - 5;
vinegar table - 40-60.
A mixture of the first three (dry) components to breed with table vinegar to the desired consistency; The resulting mask is immediately used.
Melting, eliminating the spout of nuts. In industrial radio equipment, a con-clodpage is widely used, which successfully replaces various types of tape washers.
Magnification composition (in%):
nitroemal dm- 75;
talc - 25.
The mask is divorced to the desired consistency with acetone or solvent RDV.
§ 8. Paints, varnishes, enamels, soils and putty
For metal paint, varnishes and enamels serve both anti-corrosion and decorative coating.
Details of the wood of valuable rocks with a beautiful texture (color and drawing) are covered with transparent varnishes and polishes. The wood of less valuable rocks is sometimes covered by opaque (shelled) varnishes and paints.
Wood finish with various transparent coatings is considered in Section V.
Primer. The color of metals varnishes and paints is preceded by the primer process.
The primer is practically no different from the color. The soil is applied to the surface of the parts of the middle rigidity with the brushes (and very rarely pulverizers). After drying, the soil is aligned (polished) skins № 000-180.
It should be noted that a certain primer corresponds to a specific rodukra - I (lacquer, enamel). ^ Incorrect combination of soil and coating Sometimes when - 1 leads to the fact that the paint (varnish, enamel) is bubble or after drying it is sat down.
The application given at the end of the book provides a number of the most used paints, varnishes and enamels. They also show putty, soils and, polish, the basic recommendations for the discharge, drying regime, as well as the purpose of the coatings and their properties are given.
Putty. A putty mass is applied to the primed surface with a spatula. A spatula is a flat blade made of metal, wood or rigid rubber.
If there are various irregularities on the surface of the part (cracks, chips, sinks, etc.), putty in these places are applied with a little excess (stock for shrinkage when sucking sucking). The main layer of putty should not exceed 0.2 mM..
After drying, the putty is leveled with skins No. 80-100, gradually reducing the grain of the skins. Flat surfaces are well alummed by a flat wooden bar; Between the skirt and bar, it is necessary to pave a layer of fabric thickness 2-3 mm.
Coloring. Color usually produced in two layers. The second layer is constructed by the stroke of the brush, perpendicular to the stroke of the brush when the first layer is applied. Before overlaying the second layer, the dried first coating layer is preferably aligned with the skin No. 000-180.
The painting tool most often serve soft brushes, but sometimes pulverizers (sprayers) are used. The latter are used in the color of large details of nitroces.
Air pressure during the color of the nitrocracy parts must be 1-2.5 atm. With more thick consistencies, the paint air pressure must reach 3-6 atm.
As is known, the only available high-temperature insulating material with high thermal conductivity is mica. It was "helped by" the ordinary collet pencil to solve the problem of mounting mica to the mandrel surface. So, I could only choose the appropriate pencil size and remove the tube with a slot from it.
In order not to stop the thin-walled tube, when installing a drill in the cartridge, I picked up a steel twist of a suitable diameter and drowned the edge of the tube.
Now you can safely wink the coil of the heating element.
I think you already guessed that if in the slot of this tube insert the edge of the salivary gasket, then, when winding, the turns of the wire reliably fix the gasket. After winding, the heating element can be easily removed from the tube, moving along the slot.
This is how the ready-made heating element, made by your own hands, looks like. All the subtleties of this technology you can see in the attached video.
It may be interesting. The ability to change the supply voltage at the soldering iron designed for 220 V, among other things, allows you to return to the system already buried. And to use it hereinafter, for example, with a pulsed power supply from an imported TV, which gives exactly half of the network. The reduction of these two products together and results in an intermediate version between the soldering iron with a regulator and a full-fledged soldering station. This is under the power to any radio amateur. How to do this show on the example of changing the supply voltage of the Chinese-made soldering iron, which did not cause confidence for use without refinement.
We deal with a soldering iron
To disassemble the soldering iron, it was necessary to fully twist the two screws connecting the protective casing with a heating element and holding the sting, and three screws of the fixing work part to the handle. From the wires to move the insulation and promotion the connecting twists.
Sloud with a spiral of the soldering iron
Inside the protective casing heating element. They have to do. It is necessary to make a change in the amount of the wound nichrome wire - change the resistance of the heating element. Now it is 1800 ohms, you need 400 ohms. Why exactly so much? Working currently with the UPS, the soldering iron has a resistance of 347 ohms, its power is from 19 to 28 W, the second is a desire to make less powerful here and added OM.
Rewind of soldering iron
Winding sting soldering
Powered again inserted into the heater, clamped with screws and in the cartridge drill. If there is a disassembly and opening of the excessive nichrome, holding the heating element in the hands, then everything will be much more complicated. The firmitude is removed.
Freed fiberglass and mica wrappers are removed. In the drying from the side, there is a slot where the conductor is inserted, which is inserted from nichrome to the network wire - therefore it is not unwound, and removed from it weakened mica wrapper. Mica material is very fragile. Disconnects the end of the nichrome wire. Its thickness is just over 4 microns.
Nichrome to be walked in obligatory on something round, the perfect option is a coil for threads. Unscrew - did it and so to the end. You do not need to disconnect the second end of the nichrome wire.
Soldering sprouts wire
Now you need to hide a length of 400 ohms, and in centimeters it will be about 70 (the total length of nichrome wire 300 cm is 1800 ohms, from here 400 ohms will be 66.66cm). At a length of 70 cm, a lock is set (clothespin) and in a hanging position of the coil, slightly directing your fingers, the interval is winding, which ensures its ending at the first conductor. The rate of attempts is not limited, the main thing is not to break the nichrome. At the end of the winding, a control measure of resistance is necessary.
As soon as it turned out to wind the necessary number of numeral, cut off the wire with a 2-cm wire and cling to the conductor. We put on a salivary winding, passing the conductor into the slot existing in it and press it (naturally at the top of it).
From above, we set the winding of the fiberglass and compressed with pressing, we wake the linking wire. The heating element is calculated for power supply 85 - 106 in the assembled.
Collection of soldering iron
Since the working part was fastened earlier to the handle with unusually clouded and short screws had to replace them. To do this, in places of attachment on the handle, holes for new screws were deepened.
Before making a network wire with conductors going to the nichrome heater, a plastic retainer was installed on it and the plastic retainer was adjusted.
The heating element casing ends a kind of cooling radiator, through the holes in it and is attached to the handle. Here, to increase the cooling effect, the gap between it and the handle with the help of metal washers were increased.
Test
Current consumption of soldering iron 190 mA
The UPS with a soldering iron at the outlet under load gives from 85 to 106 V. Consight of 190 mA, it is at a minimum of voltage. Power 16 W.
Current consumption of soldering iron 240 mA
At the maximum voltage consumption of 260 mA. Power 26 W. Desired received.
Heating rate
In conclusion, the test for the duration of heating. Up to 257 degrees in 2 minutes 20 seconds. An excellent result, if we take into account that from the network with a voltage of 225 in it he was heated to 250 degrees for 5 and a half minutes.
Table. Dependence of the resistance of the heating element from the power and tension of the soldering iron
And here is a table that will help navigate in the necessary resistance of the heating element depending on the desired power and the available supply voltage. Author - Babay Iz Barnaula.
The electric soldering iron is a hand-held tool intended for fastening parts by means of soft solders, by heating the solder to a liquid state and filling it with a gap between the soldered items.
As you can see in the drawing, the electric scheme of the soldering iron is very simple, and consists of only three elements: forks, flexible electric pipe and nichrome spiral.
As can be seen from the scheme, the soldering iron does not have the ability to adjust the heating temperature of the sting. And even if the power of the soldering iron is chosen correctly, it is still not a fact that the temperature of the sting will be required for soldering, since the length of the sting is reduced over time due to its permanent refueling, solders also have different melting points. Therefore, in order to maintain the optimal temperature of the soldering iron, it is necessary to connect it through thyristor power regulators with manual adjustment and automatic maintaining the specified temperature of the soldering iron sting.
Soldering device
The soldering iron is a red copper rod, which is heated by a spiral of nichrome to the melting point of the solder. The stem of the soldering iron is made of copper due to its high thermal conductivity. After all, when soldering, you need to quickly pass the sorry from the heating element heat. The end of the rod has a wedge-shaped form, is a working part of the soldering iron and is called sting. The rod is inserted into the steel tube wrapped with mica or fiberglass. A nichrome wire is wound on the mica, which serves as a heating element.
On top of the nichrome, a layer of mica or asbestos is wound, serving to reduce heat losses and electrical insulation of the spiral of nichrome from the metal casing.
The ends of the nichrome spiral are connected to the copper conduirers of an electric cord with a fork at the end. To ensure the reliability of this compound, the ends of the nichrome spiral are bent and folded twice as well, which reduces the heating at the place of connection with the copper wire. In addition, the compound is compressed by a metal plate, it is best to make crimp from an aluminum plate, which has a high thermal conductivity and will more efficiently remove heat from the connection site. For electrical insulation, there are tubes from heat-resistant insulating material, fiberglass or mica.
The copper rod and the nichrome spiral is closed with a metal housing consisting of two halves or a solid tube, as in the photo. The body of the soldering iron on the tube is fixed by the oscillates. On the tube, to protect the hand of a person from a burn, a handle is satisfied with a poorly provident heat of material, wood or heat-resistant plastics.
When inserting the soldering iron plug into the power outlet, the electric current comes to the nichrome heating element, which heats up and transmits the heat of the copper rod. Soldering iron is ready for soldering.
Low power transistors, diodes, resistors, capacitors, chips and thin wires solder 12 W soldering iron. Soldiers 40 and 60 W serve to solder powerful and large radio components, thick wires and small parts. For soldering of large parts, for example, gas column heat exchangers, you will need a soldering iron with a power of a hundred and more W.
Power supply soldering stress
Electrical solders are produced on the voltage of the supply network 12, 24, 36, 42 and 220 V, and this has its own causes. The main thing is the security of a person, the second - the network voltage in the place has soldered solders. In production, where all the equipment is grounded and there is high humidity, it is allowed to use solders with a voltage of no more than 36 V, while the body of the soldering iron must be grounded. The onboard network at the motorcycle has a direct current voltage of 6 V, a car - 12 V, cargo - 24 V. In aviation, use a network of 400 Hz and voltage of 27 V.
There are constructive restrictions, for example, a 12-W soldering iron is difficult to make a 220 V power supply voltage, as the spiral will need to be winding from a very thin wire and therefore wore a lot of layers, the soldering iron will turn out to be large, not comfortable for small work. Since the winding of the soldering iron is wound from nichrome wire, it is possible to feed it both alternating and constant voltage. The main thing that the supply voltage corresponds to the voltage to which the soldering iron is calculated.
Power of heating soldiers
The power of electric soldering places are 12, 20, 40, 60, 100 W and more. And this is also not by chance. In order for the solder to solder well on the surfaces of the sold-up parts, they need to warm up to a temperature slightly greater than the melting point of the solder. When contacting the part, the heat is transferred from the sting to the part and the temperature of the sting drops. If the diameter of the soldering iron is not sufficient or the power of the heating element is small, then giving heat, the sting will not be able to heat up to a given temperature, and it will be impossible to solder. At best, it turns out a loose and not durable soldering.
You can solder small parts to a more powerful soldering iron, but the problem occurs inaccessibility to the soldering place. How, for example, to secure a chip in a circuit board with a step of the legs of 1.25 mm sustaining of the soldering iron size of 5 mm? True there is a way out, there are several turns of the copper wire with a diameter of 1mm and the end of this wire. But the bulky of the soldering iron makes work practically not fulfilled. There is another restriction. With high power, the soldering iron will quickly warm the element, and many radio components do not allow heating above 70 ° C and on this, the allowable time of their soldering is not more than 3 seconds. These are diodes, transistors, microcircuits.
Repair of the soldering iron do it yourself
The soldering iron ceases to heat up one of two reasons. This is as a result of the inheritance of the network cord or brave the heating spiral. Most often, the cord is labored.
Checking the health cord and spirals of the soldering iron
When soldering the network cord, the soldering iron is constantly bent, especially strongly at the place of exit from it and forks. Usually in these places, especially if the network cord is hard, it is overround. First manifest such a malfunction to insufficient heat heating or periodic cooling. Ultimately, the soldering iron ceases to heat up.
Therefore, before repairing the soldering iron, you need to check for the presence of the supply voltage in the outlet. If there is a voltage in the outlet, then check the power cord. Sometimes a cord malfunction can be determined, smoothly burning it at the exit place from the fork and the soldering iron. If the soldering iron has become a little warmer, then the cord is accurately defective.
You can check the maintenance of the cord by connecting the multimeter probe plugs included in the resistance measurement mode. If when the cord is bent, the testimony will change, then the cord is pulled.
If it was found that the cord break is at the place of exit from the fork, it is enough to cut a part of the cord along with the fork and set the collapsible on the cord.
If the cord is pulled at the exit place from the handle of the soldering iron or the multimeter connected to the plug pins, during the bending of the cord does not show the resistance, then you have to disassemble the soldering iron. To gain access to the spiral connection, the cord wires will only take off the handle. Next, it is consistently touched by the arrivals of the multimeter to the contacts and pins forks. If the resistance is zero, then in the bursting of a spiral or bad contact with the cord wires.
Calculation and repair of the heating winding of the soldering iron
When repaired or with an independent manufacture of an electric soldering iron or any other heating appliance, it is necessary to wind the heating winding from the nichrome wire. The source data for calculating and selecting the wire is the resistance of the soldering iron winding or heating device, which is determined based on its power and supply voltage. Calculate what should be the resistance of the soldering iron winding or the heating device can be using a table.
Knowing the supply voltage and measuring the resistance of any heating electrical appliance, such as a soldering iron, an electric kettle, an electrical heater or an electric iron, you can find out the power consumed by this household electrical appliance. For example, the resistance of an electric kettle with a capacity of 1.5 kW will be 32.2 ohms.
| Table for determining the resistance of the nichrome spiral depending on the power and power supply voltage of electrical devices, Ohm | ||||||
|---|---|---|---|---|---|---|
| Power consumption soldering iron, W. | Power supply voltage, in | |||||
| 12 | 24 | 36 | 127 | 220 | ||
| 12 | 12 | 48,0 | 108 | 1344 | 4033 | |
| 24 | 6,0 | 24,0 | 54 | 672 | 2016 | |
| 36 | 4,0 | 16,0 | 36 | 448 | 1344 | |
| 42 | 3,4 | 13,7 | 31 | 384 | 1152 | |
| 60 | 2,4 | 9,6 | 22 | 269 | 806 | |
| 75 | 1.9 | 7.7 | 17 | 215 | 645 | |
| 100 | 1,4 | 5,7 | 13 | 161 | 484 | |
| 150 | 0,96 | 3,84 | 8,6 | 107 | 332 | |
| 200 | 0,72 | 2,88 | 6,5 | 80,6 | 242 | |
| 300 | 0,48 | 1,92 | 4,3 | 53,8 | 161 | |
| 400 | 0,36 | 1,44 | 3,2 | 40,3 | 121 | |
| 500 | 0,29 | 1,15 | 2,6 | 32,3 | 96,8 | |
| 700 | 0,21 | 0,83 | 1,85 | 23,0 | 69,1 | |
| 900 | 0,16 | 0,64 | 1,44 | 17,9 | 53,8 | |
| 1000 | 0,14 | 0,57 | 1,30 | 16,1 | 48,4 | |
| 1500 | 0,10 | 0,38 | 0,86 | 10,8 | 32,3 | |
| 2000 | 0,07 | 0,29 | 0,65 | 8,06 | 24,2 | |
| 2500 | 0,06 | 0,23 | 0,52 | 6,45 | 19,4 | |
| 3000 | 0,05 | 0,19 | 0,43 | 5,38 | 16,1 | |
Consider on the example how to use the table. Suppose, it is necessary to rewind a soldering iron with a power of 60 W calculated for the supply voltage of 220 V. By the left column of the table, choose 60 W. Upon the upper horizontal string, you choose 220 V. As a result of the calculation, it turns out that the resistance of the soldering iron winding, regardless of the winding material, should be 806 ohms.
If you need to make a 60-W capacity from a soldering iron, designed for a voltage of 220 V, a soldering iron, for nutrition from the network of 36 V, then the resistance of the new winding should be equal to 22 ohms. You can independently calculate the resistance of the winding of any electric heating device using an online calculator.
After determining the required value of the resistance of the soldering iron, the appropriate, based on the geometric sizes of the winding, the diameter of the nichrome wire is selected. The nichrome wire is a chromonicel alloy that maintains the heating temperature to 1000 ° C and marked x20n80. This means that the alloy contains 20% chromium and 80% nickel.
For winding the spiral of the soldering iron having a resistance of 806 ohms from the example above, it will take 5.75 meters of nichrome wire with a diameter of 0.1 mm (it is necessary to divide 806 to 140), or 25.4 m wire with a diameter of 0.2 mm, and so on.
I note that when heated for each 100 °, the resistance of the nichrome is increased by 2%. Therefore, the resistance of the helix 806 ohms out of the above example when heated to 320 ° C will increase to 854 ohms, which practically does not affect the work of the soldering iron.
When winding the spiral of the soldering iron, the turns are fitted close to each other. When heated, the surface of the nichrome wire is oxidized and forms an insulating surface. If the entire length of the wire does not fit on the sleeve in one layer, then the wound layer is covered with a mica and wines the second.
For electrical and thermal insulation of the winding of the heating element, the best materials are mica, fiberglass fabric and asbestos. Asbestos has an interesting property, it can be twisted with water and it is made soft, allows him to give it any shape, and after drying it has sufficient mechanical strength. When isolateing the winding of the soldering iron, the wet asbestos must be taken into account that the wet asbestos performs the eclectic current well and turn on the soldering iron in the power grid can only be completely drying asbestos.
