Nowadays, tattoos have moved into a kind of self-expression. This, now a popular art form, allows you to decorate your body with a wide variety of designs. Fans of drawing can make money on this by stuffing tattoos for other people. To start work will do even a homemade machine. We invite you to read this article and find out how make a tattoo machine.
Search for parts for a typewriter
First, find an 18 Volt motor, or if you don't find one, 12 Volt. By standard, there is a small gear at the end of the motor. Take any button and attach it super glue to the gear. It must be remembered that the 4 holes on the gear must then secure the needle, so the main thing is not to glue these very holes. Give the glue a little time to dry.
The easiest way to get the motors is from a toy car or VCR, but I do not recommend doing this. they usually have only 2-5 volts, which is not enough for a tattoo machine.
Pencil / pen for body and more
A pencil or pen will serve as the body of the machine, and its shaft will guide the needle.
Any mechanical pencil will work fine for us. Ball pen will do no worse, but you still need to work with it: get the ball, blow out all the paste and, if the hole is too small for the needle, expand it.
Bracket
The motor must be attached to a pen or pencil with a bracket. Such a bracket can be made from an ordinary teaspoon by tearing off the part that is eaten and bending the handle with the letter "G".
Needle
As a needle for our homemade tattoo cars fit a metal guitar string. Cut a piece of string so that it is slightly larger than the previously made pipe.
Assembling a homemade tattoo machine
Connect the bracket to a ballpoint pen.
Place the bracket, as seen in the photo, with its long part along the handle. Secure this structure with electrical tape. The mount should be as strong as possible.
Attach the button motor in the same way.
Pull the string through the pen / pencil. Bend it at the end with the letter "P" and insert the buttons into the hole.
Connect the finished machine to the power supply.
For power, use any source with a voltage not lower than that of the motor being used.
In 1999, a few months before my dismissal, I was summoned to their company by senior conscripts. Since I was a staff artist in my company, I was asked to draw a tattoo blank and then fill it up. They said the typewriter is made of a pen, so it's pretty much the same thing. They gave me a barbaric battery-powered unit and said: "Come on." So I "learned" to make "tattoos".
Already in civilian life, I made myself my own typewriter, and to be honest, it earned me many times more moneythan its components were worth. At first I worked as a friend - for ink and gaining experience. And "friends of friends" have already done for "grannies". I will not tell you anything new here, I will just try to present everything in detail if possible, with a description of some subtle points that have been developed over several years, or collected bit by bit from different sources.
Close-up
So, the type of machine is rotary. The scheme, as far as I know, is the most common among DIYers. If all components are present, it is assembled in 15 minutes. Necessary parts: a gel pen with paste, a motor from the player, wires, a string, a power supply (preferably with a variable voltage), a motor holder (to be described below).
Requirements for spare parts. The main thing is the motor. It is really most convenient to take it from a player or tape recorder: small size quite strongly affects the further ease of use. I once held in my hands the same shaving machine with a mechanical winding (!), Which was often used to make machines in soviet time... It is hard and inconvenient to work - too much load on the wrist. However, the most important requirement for a motor is that its roller is plastic, not metal. Otherwise, you will have to glue all sorts of plastic discs on this roller, which complicates the design, and, accordingly, reduces reliability (it is very inconvenient to repair the machine in the middle of the stuffing process).
Power Supply. As practice has shown, variable voltage is sometimes very useful, as it allows you to fill faster. If the person is in too much pain, the speed can be slowed down - sometimes it also helps. The main thing here is to determine the maximum voltage that your motor can withstand, and make sure that the string does not fly out.
The strings are taken from the guitar and the thinnest. However, there are times when you work with what you got. Thick strings can also be used. The winding is removed from them, and the base is processed in the same way as for the thin one.
It is better to take soft wires so that they hang freely, and not "stand with a stake". In addition, rigid wires (which were bent and they remained in this position) have a stronger effect on the place where they are soldered to the wires of the motor. The fragility of these wires leads to frequent breaks. If it breaks off under the very motor, it will have to be changed completely.
The motor holder can be made from tin can... However, I was lucky to buy an automatic pencil that had a handy metal clip for grabbing onto a pocket, etc. I just took it off and used it as a bracket. Then the illustration will show in more detail.
Assembling the case
We take a gel pen, untwist it and remove the paint from it. We squeeze the ball out of the metal spout of the rod with a needle from the inside. This creates a hole, but it is too narrow for the string (the thickness of the strings can sometimes vary), so you need to widen it. We take a small file or a file and grind it down a little so that the string can walk freely back and forth (otherwise, at high engine speeds, it can get stuck, which will come to its flight and the subject's frightened sidelong glances).
The handle body itself will have to be shortened by about half to reduce string consumption. A simple calculation: a whole pen - you will have to make a string in its entire length, half a pen - a string is half the size. Thus, saving the consumption of the string, besides, the subsequently fixed motor will lie on the bend of the hand, and not balance in the air.
A tube from the rod is also needed. Its approximate length is half the size of the pen body. The meaning here is this: the string vibrates strongly when the motor rotates, such a mechanism allows it to be gently adjusted in the desired direction. In addition, sometimes ink rises up the handle (capillary effect, etc.). If there is no such limiter, it can smear the handle from the inside, which is ugly, and can interfere with changing paint - you will have to wash it more thoroughly.
Still important detail: A small hole is made in the plastic spout of the pen, where ink will accumulate. As a result, you will have to dip the machine less often in a jar of paint, which is very convenient.
The result of working with a gel pen in the picture. The rod is presented in two possible versions.
Assembling the motor
There can be a bunch of options for mounting a motor - as far as imagination is enough. I used a pencil holder and tape it in. The convenience here lies in the fact that no matter how much you calculate the length of the string, you will still be mistaken. And the string should come out very accurately from the spout of the rod. Due to the fact that the motor bracket is not firmly fixed, I can adjust the position of the string by moving the motor back and forth along the handle body.
In addition to fastening, you need to make a small hole in the roller. This is done with a red-hot needle. The hole should not be too large to prevent the string from falling out. In case of an error (like mine), you can make a couple more holes. Only then we must not forget which of them came up best.
String processing
After a bit of searching on the web, I found no intelligible description of how to handle a string. homemade cars... Meanwhile, this is one of the important and painful (for the subject) moments. An incorrectly made string hits worse, spoils the clarity of fine lines, and delivers more painful sensations. Therefore, I describe it step by step:
We take a string, roughly outlining how much length we need. For example, we fix one end of the string with a hand with pliers. With the other hand, lightly pull the other end of the string. In the place where we want to make a sharp nose for the future needle (usually we choose a place closer to the pliers in order to save material consumption), we bring the lighter with the third hand and heat it up (what, there are not enough hands?). In this case, the string must be pulled. In a heated place, it will first glow red-hot, then become thinner, and then burst.
Initially, the string is elastic and does not want to take a straight shape. It is necessary to "persuade" it to become smoother - red-hot once. Having verified the required length of the string, we bite off the main skein with pliers. We bend the rear end, which will be attached to the motor, with the letter "g". Do not overdo it with its value, so as not to cling when the engine is running.
In the harsh army (or Zon) conditions, the string is sharpened, about which you have to: first about zero, then about matchbox, then on the glass (which is not - you can throw it out of the list, the process will just take longer). I have always sharpened the needle on the smooth grindstone for knives, pressing the tip with your finger. Any shape can be given to the string: both cone-shaped (like a sewing needle) and flat ones (a kind of "spatula" is obtained - in one plane it hits a thin line, and in the perpendicular direction a wider one).
Another subtle point: the needle should be slightly bent at the end. Thanks to this, it will spring and hit at one point. If you make it straight, then when you exit the tip of the pen, it will hit anywhere, which will complicate the drawing of straight lines.
It is advisable to wash the finished string with soap (advice from an experienced surgeon), since soap dissolves biological substances (infection), while alcohol "burns" it to the metal surface. Of course, the best way - combine both. If conditions do not allow having several strings, its tip must be ignited with a lighter. But over time, this can worsen the properties of the metal, make it completely brittle.
The finished version of the processed string. It looks too dirty, but it is the color of the calcined metal and there is no infection on it. Although the Sanitary and Epidemiological Station would probably swear ...
Debugging work
Oddly enough, it is not enough to assemble a typewriter. It is also necessary to adjust its mechanisms so that they work without failures. During practical activities some patterns were found. The elimination of minor inconsistencies greatly simplified my work, and the test subjects reduced the "sadomasochistic pleasure".
In the beginning, the biggest problem was string breakouts. From the inside, she buried herself in the nose of the handle and jumped out of the mount on the roller. The solution was this: it is necessary to adjust it so that when the string is in the extreme rear position on the roller, the sharpened end of the needle comes out of the handle by only half a millimeter. It was here that the ability to adjust the position of the motor on the handle came in handy, since it is quite difficult to adjust the size of the string with an accuracy of half a millimeter.
However, it is not enough to adjust the position of the motor along the length. Its height relative to the centerline of the handle is also important. That is why I used a piece of tubing from a regular ball rod. Its function was to bend the string closer to the motor shaft. It looks like a nipple system, but this has significantly reduced the number of overhangs due to the weak attachment of the string to the roller.
Also, when the pen spout was first dipped into a container with ink, all the air did not come out of it. It led to the formation of a foamy droplet on the nose - it looks like there is a supply of paint, but nothing remains on the skin. You just had to blot the hole on the nose of the pen with a rag (an air bubble formed there) and re-dip it in the paint.
Hygiene
"Cleanliness is the key to health." In all my humble practice (for about 6-8 years I was engaged in tattooing quite tightly), I only had two unpleasant overlays, when a full tattoo caused complications. First, I made a pattern for a friend of mine who was working as a road builder at the time. Literally on the second day, he was already waving his pick at some object - in the very sun, without a bandage, without protecting himself from dirt, sweat, etc. The result - she instantly faded, burnt out in the sun (in our Crimea, it is quite hot and sunny in summer), and went acne. Naturally, the paint "fell out" in places and had to be interrupted.
The second case - the girl wanted a pattern of flowers on her tailbone, and immediately after that she tore off my bandage (she has jeans, you see, "on her hips") and went to play with her ass at the disco. Moreover, she had some kind of special skin - any infection caused wild scars on her. When I saw that lumpy ugliness located under the tattoo and a little next to it, I almost felt bad. After all, I cared so much about the sterility of my equipment. And when I found out why and under what circumstances this happened, I wanted to kill her in a sophisticated manner. Repeatedly. It was so insulting for my painstaking work. The scars had to be masked with new rosebuds. It looked fine, but "the sediment remained."
Thus, it is necessary to carefully monitor the cleanliness of the machine: ideally, all homemade parts that come into contact with the subject's skin (string, pen body, used ink in the cap, the cap itself) should be disposable. You should not save on this - these things cost a penny. Especially compared to the prospect of infecting your friend with AIDS from a previous unfamiliar friend. A former classmate of mine told me about this when five guys contracted syphilis in a military school in a similar situation. He carried him over, but it is not pleasant to be substituted like that.
When applying a tattoo, certain rules must be followed:
A person should be well-eaten - blood flows to the stomach, bleeding is reduced, accordingly, it is easier to beat, the paint is not washed out of the skin.
The body must be sober (preferably in both) - the blood vessels dilate from alcohol, and the pressure rises, which leads to increased bleeding.
The patient's skin and the executor's hands must be thoroughly washed (it is not very convenient to work with gloves - you "feel the skin" worse). In general, gloves are a "wiggle" for shy clients, since, in addition to everything, they must also be sterilized. And the mere presence of gloves (in which they could stuff other people as well) is not an unequivocal guarantee of the purity of the process.
It is necessary to wipe the skin, removing excess paint and blood, with a clean cloth (bandage, cotton) dipped in boiled water (this significantly reduces the "crust" on the stuffed tattoo, shortens the healing time), and not alcohol. Alcohol leads to burns, disrupts the healing process of the skin. Alcohol can be used for additional sterilization of already clean equipment (just do not pour it into the power supply unit - it takes a lot of offense).
After tattooing, it is advisable to wash the skin in this place with warm water and soap, apply a healing ointment (I always used the "Rescuer", and in the army they used aftershave cream) and apply a bandage for a day so that it does not rub on clothes.
If you worked at home and take out the dirty, bloody bandages afterwards, don't show them to your mom. The reaction is much stronger than those bandages. Say it's red ink.
In the end, it is necessary to instruct the patient "to tears":
so that he does not take off the bandage for a day;
did not comb the "crust", no matter how it itched;
after a day has passed, you can wash, but not become limp;
do not sunbathe until complete healing, and then use an OT sunburn cream - otherwise the paint may fade a few years earlier;
if you smear it 4 times with the Rescuer for a day, it can heal in just a couple of days (although this is an individual indicator - in practice it healed in a day, or two, and sometimes a week).
Just in case, hint that if he does not obey and scores on these recommendations, you will come to him at night in a dream and with an ax - sometimes it helps. Yes, in most cases he will come after a while and ask for more. Tattoo is like a drug - addictive.
Psychophysiology
An abstruse word, but it cannot be ignored. Over the course of my work, I have heard a lot of scary storieslike on some mentally weak people may affect the image on the skin. If some "major" wants to fill himself with a pattern, "yin-yang-crap" or "dragon for 30 bucks", then for him it most likely means nothing - he just wants to "show off". Especially to girls, explain that this is not makeup, and not earrings - this is for life and is very difficult to remove. Although sometimes girls do not come for a tattoo. :)
It's another matter when a tattoo means something important for a person: some kind of psychological image, a combination of emotions after the experience, the memory of an event or another person. Such an image on the skin, supported by internal motives, becomes for a person as an algorithm of thinking or even an element of zombie. A couple of examples from life. One comrade asked me to get him an army tattoo. He served in the Soviet Union, in the rocket unit and grandfathers for all young people were forcibly stuffed with the "symbol of the unit" - a laughing devil with a bottle and a cigarette, sitting on a rocket. The main problem besides the ugly performance - even when it was bad at heart, the man did not stop smiling: “He laughs, and I must. I’ve gotten enough myself, but I can’t stop it.”
Another incident was with my friend, when his father was framed and imprisoned. The guy walked loaded, with a killed look and a dull look. It is clear that his soul was gloomy. I asked him to fill him with a wolf and an inscription on foreign language "Man is a wolf to man." Barely dissuaded. It is clear that for him this could become a demeanor for life. After much bickering, the inscription was replaced with an abstract background. And Dad came out a couple of years later, and life got better.
One friend asked to fill her with a panther with a crown. A large girl of average height, with huge boobs (she once did bodybuilding and ate a lot, then she gave up sports, but her appetite remained) and a lively disposition - she was a downtrodden child, cuffed by her authoritarian mother. Mom was also a shot. Even a roommate ran away from her (karate, prize-winner of competitions) - she threw everything at him during quarrels: from pans to bricks. By means of a tattoo, the girl wanted to either express her "protest" to her mother, or to rise in the eyes of those around her, but did not know how to do it correctly. Many such acquaintances have addressed me "with complexes". After the tattoo, they almost immediately changed in their behavior - they began to associate themselves with the formidable images depicted on the body. Joking aside, that mother almost let a hefty dog \u200b\u200bdown on me ...
There were also quite mystical stories. You can believe or not believe in any parapsychology or energy, but sometimes it matters - who, what and with what thoughts stuffs a person. I heard how some guy painted a beautiful, meaningless picture on the body of one girl. Either his "eye" was "heavy", or he was fond of Satanism, only that friend began to feel sick until the drawing was washed off. Think about it now: either something was wrong with the guy, or the girl has made a movie for herself. I know one thing - you cannot wish evil on the person you are stuffing with something. And if possible, he should be discouraged from doing any "necrophilia" on the skin - attracts bad thoughts, negative energy and sidelong glances of others.
Thieves' tattoos
I will say "a little, but delicious": I heard a couple of stories about how ignorant people stuffed themselves with beautiful tattoos with a Zonian meaning. One filled himself with a woman seduced by a snake ("rooster"). Comrades came up and asked to "serve". The boy began to excuse himself that this was a misunderstanding. With the words "for the suit you need to answer" his skull was broken.
The second fool has filled himself with something of the suit of "thieves in law." Perhaps an epaulette or something. People came up and spoke respectfully on a hairdryer. They see that the comrade does not understand - they were offended for the deception and also punched their head off. Hence the conclusion: before you hit, clarify carefully whether the picture has a thieves' connotation. You can keep the man alive.
Total
It's really easy to assemble a tattoo machine from scrap materials. If you have all the components, the assembly process will not take long. And it will cost a penny compared to the prices of factory products. The main thing is for a person to be able to draw. I have seen the work of the so-called "professionals" several times. They were made on factory equipment, with "real" paints, for a lot of money, but with crooked hands. And they looked much worse than my work - on a self-made typewriter, sharpened with a string and Rotring drawing ink - which I stuffed with friends for virtually free. After all, it is not a matter of technique, but of hands and artistic taste.
I can remind skeptics that the most unique works were done in ancient times by Japanese and Chinese craftsmen - an ordinary needle (and sometimes a fish bone) stuck into bamboo stick... In doing so, they achieved stunning effects and smooth color transitions. Using only a few natural dyes, they mixed many shades of them. Today, many of the secrets of that time are irretrievably lost.
I am not ashamed to admit that I never became a real master. I can only fill in what I can draw. But it's nice to hear when, after five to six years, friends' tattoos still like them and continue to attract someone's attention.
Greetings, dear readers of my blog, from the title it is immediately clear what this blog is aimed at and now I want to write detailed instructions About, how to make a homemade rotary tattoo machine.
I don’t want to write a long preface, but I read all the manuals for creating my own wheelbarrow from improvised materials and, alas, they disappointed me, I think that the instructions should be more understandable for a beginner, so I decided to write it myself, let's go ...
First, let's think about what we need:
1.
Motor for ~ 9V.
2.
A pen.
3.
Clamp.
4.
String.
5.
Charging from an old phone.
6.
Corner.
Let's look at everything in order:
1.
The motor may not necessarily be 9V, but this is the most the best option... The motor can be bought on the radio market, for example, I took it out of an old tape recorder.
2.
The pen is the most important element our machine, it must meet certain requirements. I have tried many types of pens in order to creating a rotary tattoo machine and finally found the best option. The handle must be capillary, now a little more ...
This is what a capillary pen looks like, as you can see, it has a metal tip through which the string fits perfectly, which means this is what we need! The price of such a "tool" is not as high as it might seem to you, for example I bought such a pen for 32 rubles.
3.
I bought a clamp for the size of my motor with a small margin, as far as I remember the size of my clamp is 15x20mm, it cost me 15 rubles, a penny to put it simply :)
4.
The string is also not an unimportant attribute of our car. Before that, I bought the wrong strings and it didn't work out for me. I took strings in the form of a spring, but I need to buy a string "two"! It is thin and comes in the form of a uniform, metallic wire.
5.
I found the charger in the deposits of my trash, but even if you don't have an old charger at home, you can easily buy it within 50-100 rubles on the local internet forum.
6.
It is not even necessary to buy a corner; it is quite possible to find a thin metal plate and make a corner of the desired size from it.
Now I will finally write about how to assemble our miracle unit:
1.
We need to completely disassemble our handle: 
2.
Then make a corner, I made it from construction fasteners, cutting out this way: 
The resulting plate is: 
3.
We bend our plate and fasten it to the handle with electrical tape: 
4.
We pass a string through the body of the handle and cut it off with a margin, I cut it with scissors for metal, it is probably better to use nippers ... 
5.
Now we need to convert the rotational movement of our motor into the translational movement of the string, for this we melt a hole with the help of a heated needle in the plastic tips of the motor, into which we insert the string, something like this: 
6.
We attach the motor to the corner on a clamp, like this: 
Bend the edge of the string 90 degrees and insert it into the previously melted hole.
7.
On the opposite side of the motor, the string should come out through a metal insert: 
8.
Then I soldered the pins from charger to the motor, do not be afraid to confuse "+" and "-" - this not important! 
Then I tightened bare wires thermo-shrinkable tubes, if you do not have such tubes at hand, then you can use ordinary electrical tape ... 
9.
Cut the string to the desired length. I pulled the string to the farthest point of the lunge and cut almost all of it: 
10.
That's basically all, it remains only to sharpen! I recommend using my mother's nail file :). Let's calculate the maximum costs for assembling such a machine ...
1.
Motor - 100 rubles.
2.
Pen - 35 rubles.
3.
Clamp - 15 rubles.
4.
String - 30 rubles.
5.
Charging - 100 rubles.
6.
Corner - 10 rubles.
Total 290 rubles.
I will be glad to your comments, I will answer all questions, pis everyone!
This instruction will tell you how to make a tattoo machine at home. In order to get a tattoo, you don't have to go to an expensive tattoo artist or buy special equipment.
With a little effort, it is possible to make the necessary equipment yourself.
To work, you will need to find the following parts at home:
- Electric motor.
A motor from a children's toy with a voltage of at least 12 volts will do. A motor with a lower voltage is not needed - it will be too weak for such a purpose. - Power Supply.
Any unit with a voltage of at least 12 volts will do. - Gel pen or mechanical pencil (plastic or metal).
It will serve as the body of the device, as well as guide the needle inside the machine. - Brace.
This will attach the motor to the gel pen. The staple can be made from metal, for example from a regular tablespoon, by removing the part that is used for food. Instead of a spoon, you can use a toothbrush, heating plastic handle a lighter and bending it with the letter "G" (an example is shown in the figure). - Insulating tape.
- Needle.
A regular guitar string is used as a needle (it is better to buy a new string in a specialized store). Choose the thinnest string. - Button with 4 holes.
Assembling the device
Take a pen, disassemble it and remove the ink from the refill.
Rinse the rod well, no ink should remain there. Using a file, grind off the metal tip of the rod so that the string can pass through without effort. Cut the rod about halfway (this is necessary to reduce string vibration).
Preparing the motor: a button must be attached to the motor axle using super glue. Make sure that the adhesive is completely dry before assembling the device.
The connection between the motor axis and the button should be of good quality and not loosen over time. Do not fill the rest of the button holes with glue - they will still come in handy.
If a plastic gear is attached to the axis of the motor, you do not need to glue the button, but make a hole for the string in the gear with a red-hot needle.
This is done as follows: first of all, the L-shaped bracket and the handle are connected using electrical tape. Tightly tape the clip to the handle with several layers of electrical tape so that the bend of the clip and the top end of the handle are flush.
To the other part of the bracket, the motor from the toy with the glued button should be wound in a similar way.
Now you need to pull the string through the handle and cut it, leaving some margin. Then the end of the string is bent a few millimeters and passed through one of the button holes (or through a hole in the gear).
As you rotate the motor axis, you will notice that the string moves up and down. The end of the string sticking out of the rod is cut in such a way that when the motor rotates, the string is shown from the tip by 3-4 mm. Sharpen the string with a knife-turning bar.
The power supply is now connected to the engine. For convenience, a switch can be attached to the machine. The device is ready to use!
Don't forget about safety and hygiene! Use a new string and a new tip every time! Boil the string in water for at least 10 minutes before use.
These simple rules will help you avoid contracting diseases such as HIV or hepatitis.
In the army, I learned how to assemble tattoo machines, as well as draw and beat half-dead tattoos. I will reveal the secrets of an unprofessional cuisine: cattle most of all love to stuff themselves with scorpions. A huge number of demobels are now carrying identical scorpions, not without my assistance, on their arms and backs. The soldier's main friend is a tattoo "For the Air Force" or "For the Airborne Forces", stamped on the edge of the palm, so that when vodka is poured into his mouth, drinking companions show this inscription. The images of such animals as scorpions, tigers, dragons are held in high esteem. You can also make a meaningless pattern (Celtic, tribal). Each drawing should, according to thieves' "concepts", mean something neutral, therefore, the meaning of the picture is of interest in the first place. Even details such as open / closed scorpion claws, raised / lowered sting are important.
But the main thing in this matter is the apparatus itself. Assembling a homemade tattoo machine is a simple matter.
To create the device, we need the following items:
Gel pen:
Motor (a motor from a tape recorder, cassette player, VCR, printer is suitable, well, at worst, a motor from a Soviet children's toy will go): 
Eraser: 
Guitar string (first or second): 
Electrical tape (or tape): 
Charger for phone or power bank for Dandy: 
Let's start by breaking off the devouring part from the spoon, and bending the other part at an angle of 90 degrees. 
We will cut the handle together with the rod. Correct uneven edges with sandpaper or a lighter. 
Let's cut out a similar shape from the eraser: 
Let's put her on the spit of the motor. 
We take the ball out of the handle, maybe even bite it out with nippers. 
Let's bite off with the same pliers a string of size longer than the handle centimeters by four. The string now needs to be sharpened against sandpaper, a whetstone, or a matchstick from matches. 
Let's estimate what can come of all this. 
Let's apply electrical tape. The rod should rise above the upper plane of the eraser by a millimeter or a couple. When rotating, the eraser should not touch the handle. 
We bite off its connector from charging and strip two wires. 
We solder or simply twist the charging wires and motor contacts, insulate abundantly with electrical tape. 
The string, coming out of the back of the rod, is bent at 90 degrees, passes through the eraser and bends at the bottom of it. The principle of operation is the reciprocating movement of the string, produced by the rotational movement of the crankshaft. On the other hand, where the tip of the string is located, there are also rules: the tip should not protrude from the rod by more than 5 mm.
The machine is ready for grievous bodily harm. 