Terms.
To do this you will need the following materials and tools:
- medical syringe (this homemade product uses a 20 ml syringe);
- insulated copper wire with a diameter of 0.45 mm and a length of about 5 m;
- copper wire with a diameter of 2.5 millimeters;
- neodymium flat magnets 2 pieces;
- board for making a wooden base;
- hot glue gun;
- a tube of super glue;
- Krona battery with a voltage of 9 volts.
Let's start by making the basis of our engine - the electromagnetic cylinder. Let's make its body from a 20 ml medical syringe. Such a syringe can be purchased not only at the pharmacy, but also at service centers or stores that sell and service office equipment. Employees of such centers use syringes to refill inkjet printer cartridges and, as a rule, they mainly use syringes of the required volume, namely 20 ml. We take the syringe and first remove the plunger; it will not be needed. Using a hacksaw, cut off part of the syringe (the mark is the 15 ml division).
We put the excess aside, and we will continue to work with this workpiece.
Next you will need thin copper insulated wire. In this homemade product, a wire 5 meters long with a cross-section of 0.45 mm was used.
It must be tightly wound in one direction in several layers onto the cylinder obtained from the syringe.
We twist the ends of the wire together in this way. We fix the winding with superglue.
Then you will need thick copper wire from which we will make the crankshaft and connecting rod.
First, let's remove the insulation.
Next, using pliers, we shape the wire into the shape of a crankshaft.
From the remaining part of the wire, using pliers, we will make the next part - a connecting rod. To make it, you need to bend the wire at both ends as shown below.
Then we connect both parts (connecting rod and crankshaft) together. To fix the connecting rod on the crankshaft, two pieces of insulation from the copper wire from which these parts were made are used. First you need to put on one piece of insulation, then the connecting rod and then another piece of insulation.
Next you will need two neodymium magnets of such a diameter that they can easily move inside the cylinder.
You will also need a part of a similar shape (it can be made, for example, from wood), which we attach to magnets with hot glue.
Then we fix the resulting part as follows:
Then you will need a wooden base and two wooden support posts. These design parts can be made from any material, the main condition is that it should not conduct electric current. But I believe that this design is easiest to make from a piece of wood (in this case, a board), since wood is a very affordable material and quite easy to process.
Based on this, we outline the future location of the cylinder and support posts. Then use hot glue to fix the cylinder on a wooden base blank.
Next, insert the crankshaft into the support stands. Then use hot glue to fix the racks to the base according to the markings.
Then, using small pieces of insulation, we limit the movement of the shaft in the support posts.
We install a flywheel on one side of the crankshaft. It will ensure smoother engine operation.
Then you will need two contacts made of copper wire, which must be secured to the base using a self-tapping screw with a wide washer.
Then we connect the cylinder winding to the contacts. Before connecting, the ends of the winding must be cleaned of insulation (varnish).
At one time, when King Hammurami still lived, he argued that the time spent fishing is not included in the calculation of the total life time. This is also confirmed by many citizens who like to spend part of their free time fishing.
Typically, most anglers own a boat. Many boats, especially modern ones, are equipped with gasoline engines. And a boat without a motor, especially if you have to fish in the waters of a large lake, becomes a burden that requires enormous costs, effort and energy to move. And here you definitely need a motor: gasoline or electric - it doesn’t matter.
Still, special attention should be paid to the electric motor because:
- electric ones do not require either oil or gasoline to operate, which means there are no exhaust gases, which does not harm the environment;
- electric motors are smaller in size, lighter in weight and do not take up much space. This is especially true if you have to fish far away, and every kilogram of excess weight is always felt;
- they are much more economically profitable than their gasoline counterparts;
- modern designs are assembled using modern parts developed using modern technologies, therefore they have maximum power with minimal weight.
But these statements only apply if the boat owner already has an electric motor and has experienced such benefits to the fullest. But what to do if it is not there? This means you need to do it yourself.
Many enterprising boat owners use a drill or screwdriver that runs on batteries, since the industrial design of the electric motor is based on the same principle. The basic layout of such a unit is almost the same for all models and looks like this:
- the battery is the power source;
- the electric motor acts as a boat engine;
- a propeller with a gearbox is a working tool that allows the boat to move through the water;
- control unit - consists of a knob for turning the direction of movement and changing the speed of rotation of the electric motor.
Almost all elements can be found in an electric drill or screwdriver. In this case, one should take into account the fact that industrial devices are hermetically sealed, which allows the main components to be in the water.
If you use an electric drill, it is advisable that it be located away from water. This is the only problem, quite serious, that requires a technical solution. The slightest splash of water on the control unit can damage it, which will lead to the boat stopping.
Advantages of such a model
If you take an electric drill, you should always remember that its main value is the engine and the speed control unit (button). Choosing a drill or screwdriver has some advantages compared to buying an industrial outboard motor:
- in terms of price, this purchase will be much cheaper than buying a factory model;
- according to the law, it is necessary to adhere to the requirements related to the power of engines used on various bodies of water;
- the electric drill is powered by a battery or other power sources with suitable parameters;
- The electric drill is easy to repair, thanks to the availability of a sufficient number of spare parts on the market.
When choosing a drill, you should take into account the fact that it is mainly designed for operation in cyclic mode. If the drill is installed on a boat, then you need to count more on a continuous cycle of work. This means that you need a reserve of power, otherwise the drill will overheat.
In such cases, you should opt for a power of 150 W or more. The power reserve will allow you to work with a propeller with a diameter of 130-150 mm. In addition, you need to take into account that the total weight of the boat will be 300 kg, no more. We can assume that this is the maximum weight.
You should immediately pay attention to the fact that drills and screwdrivers are available in different operating voltages, such as 12 V, 14.5 V, 16 V, 18 V and 24 volts. Batteries are also produced for the same voltage. And yet, the capacity of standard batteries that operate an electric drill or screwdriver under classic operating conditions is not enough to ensure the necessary movement of the boat on the water. In this regard, it is better to pay attention to a car battery, which has a much larger capacity. And since a car battery produces 12 V under load, a drill should be selected with an operating voltage of 12 V.
Naturally, you can make a battery from a set of manufactured batteries for power tools for any voltage, but this can be much more expensive.
Required tools and materials
For such a device you will need the following parts:
- electric drill for motor;
- clamps for mounting the motor (drill). Both ready-made factory and handicraft ones are suitable;
- the gearbox from the grinder is suitable if the motor is installed on the transom of the boat;
- round tubes with a diameter of 20 mm and profiled tubes 20x20 mm. A rod and a mount for the motor (drill) will be made from them;
- a round rod of metal from which the motor shaft will be made, as well as sheet metal for the propeller.
The following tools may be needed for work:
- metal scissors;
- welding machine, although you can do without it;
- electric drill and set of drills;
- grinder with cutting and grinding wheels;
- if the structure includes wood, then nails or screws (as well as wood).
The presence of a lifting mechanism radically simplifies the operation and maintenance of the entire system, especially since there are cases when it is urgently necessary to lift the propeller. As a rule, such a mechanism controls the position of the electric motor in all planes (vertical and horizontal).
As an option, we can propose the following design of such a mechanism: the motor is attached to the transom of the boat using clamps, which are rigidly fixed to the plate. The clamps are equipped with rings through which the tube is threaded, and the motor shaft is threaded through the axle welded in the center of the tube. This results in a very simple articulated joint that can provide normal motor control.
As far as we know, the drill is designed for drilling holes and has a high final speed, which is not acceptable for supporting the operation of a propeller, which operates at slower speeds. Therefore, in order to reduce the speed transmitted to the propeller, the installation of a gearbox is required. Sometimes you need 2 of them, depending on design solutions. The upper gearbox should reduce the drill speed from 1500 to 200-300 revolutions, which will ensure normal boat movement.
The lower gearbox is used for horizontal installation of the propeller. When using a gearbox from an angle grinder, it is simply clamped in the drill chuck.
The manufacture of a propeller propeller begins by marking it on a piece of steel sheet. As mentioned above, its diameter should be no more than 130-150 mm. You can take a square of metal, 200x200 mm in size and 2.5-3.0 mm thick. It would be better if it was stainless steel, although it is much more difficult to process. As a last resort, you can use the impeller from an air exhaust fan or car cooling system. At the same time, it should be taken into account that the impeller profile is designed to work with an air mass. In this regard, you will have to start making it yourself.
A hole is drilled in the center of the square for the landing screw. Slots are made along the diagonals so that the sheet remains intact in the center up to 25-30 mm. After this, they begin to form the shape of the blades. Typically, they have a rounded appearance. In this case, you need to ensure that the blades are the same size, otherwise there will be vibrations. After this, the blades are slightly turned to a certain angle. In this case, the direction of rotation of the blade must be taken into account.
Since manufacturing takes place at home and, as they say, in order not to break off in the water, tests should be carried out. Any container of water that will fit the propeller will be suitable for this. Naturally, the larger the capacity, the better. As a last resort, if possible, it is recommended to go out into nature, to a river or pond and test it in action without installing it on a boat.
When the engine is running, a directed stream of water should be observed and felt. In addition, no serious vibrations should be felt. If the propeller is not operating at full power, you can modify it by increasing the angle of the blades.
The motor control system is modified depending on the wishes of the boat owner. The main thing is that it is convenient to manage. It is better to move the engine speed control button to a convenient place.
The following components should be included in the calculations:
- weight of the boat when fully equipped;
- power consumption of the electric motor;
- current and operating voltage.
During the assembly process, you should take an electrical measuring device and make sure that the engine power matches the load power. The engine power must exceed the load power. It is desirable that the engine power overlaps the load power by at least 20%.
If the engine power matches the power consumed by the electric drill: if the power consumption, calculated by the formula P = 12V x Ipot, corresponds to the declared power of the engine (electric drill), then we can say that everything is done correctly and the electric drill can be used as a motor for a boat. At the same time, we should not forget about the 20% power reserve. It will definitely be needed in case of emergency situations.
During the setup process, it is better to experiment with the impeller to select the correct blade configuration. As a rule, their shape significantly affects the economics of engine operation.
Using the windshield washer motor
Some owners who decide to make their own electric motor for a boat use various 12V engines that are used on board the car.
Such engines are perfect for such functions, if only because they are designed to run on a car battery. Despite this, they require some improvement.
Boat owners are constantly experimenting and finding amazing solutions. The high cost of industrial designs forces them to do this. As a result, the idea of installing a lawn mower motor on a boat was born. These are engines with a power of about 6 hp, which are designed for long-term operation under load in various conditions. Such an engine can be adapted to a boat if you use various spare parts intended for repairing Soviet boat engines.
Motor from the Ural-2 chainsaw
Some craftsmen easily adapted motors from Soviet chainsaws as motors for boats. At one time, a huge number of chainsaws were produced, the quality of which needs to be discussed separately. Despite this, some motors installed on boats still serve today. The main thing is to calculate everything correctly.
Electric motor application
This is a very interesting question. The use of conventional AC motors has been discussed for a long time. Such motors do not have a brush mechanism, so they are very easy to operate and operate.
But there are some factors that have to be taken into account. The first factor is the presence of an alternating voltage of 220 V. Alternatively, it is possible to install an inverter that can convert a direct voltage of 12 V into an alternating voltage of 220 V.
The second component is safety, because 220 V voltage is very dangerous for humans, especially on water. This requires special measures. But if there is water all around, it is difficult to even imagine what exactly these measures should consist of.
There is an almost ready-made option - this is the use of a motor from a trimmer or from a brush cutter. Almost everything is ready here, all that remains is to decide on the length of the device and install the propeller. There is no need for an upper gearbox and no need to modify the control system or engine power supply system.
The main task is to properly secure such a device on the boat. This is especially true if you have an inflatable boat.
Conclusion
The production of such structures is available only to those boat owners who are in constant creative search. On the other hand, most of the boats are owned by anglers who are constantly experimenting. Therefore, it will not be difficult for them to realize their ideas.
Naturally, creative people or people whose family budget does not allow them to purchase both a boat and a motor for it are engaged in the independent production of various designs. Therefore, some fishermen still use oars and do not regret it. They are only satisfied with the fact that they have a boat, since there is another category of fishermen who do not have such a boat. They enjoy fishing from the shore and envy those fishermen who have a boat, although without a motor.
Making an electric motor from what you have at hand is not at all difficult.
I came across the idea for such a motor on the website www.crafters.ucoz.ru As you can see in the photo above, for the motor we will need adhesive tape, a couple of pins, a magnet, a battery and a piece of copper wire.
Instead of a regular battery, it is better to take a battery because the battery charge for such an electric motor will not last long. Take copper wire and wind 30-50 turns around the battery.
Secure the ends of the wire to the opposite edges of the resulting rotor; they will serve as the axis. They can be tied in a knot.
Clean both ends of the wire from the varnish insulation with sandpaper or a knife.
Now take a battery, tape and pins, attach the pins with tape to the battery contacts, insert the prepared copper rotor into the ears of the pins.
ATTENTION! At this moment, the circuit of our rotor closes the battery contacts and it is not recommended to keep this structure in a “quiet” position for a long time! The battery electrolyte can get very hot, so do not make the rotor less than 30 turns, the more the better (more resistance). Now place a magnet under the rotor on the battery, it will “stick” to the battery itself. The rotor will begin to rotate quickly.
The rotor should not touch the magnet and it would be even better if the magnet is at a distance of 5-10 mm from the rotor. Try the magnet in different positions, rotate it, try to move it away from the copper rotor, achieve maximum rotation speed.
This is the simplest example of an electric motor, we went through its circuit more than once in physics lessons at school, but for some reason we were never shown this simple and interesting design :) Let's watch a video of how this homemade motor works.
[video lost by rutube]
To understand the process of making an asynchronous electric motor with your own hands, you should know its structure and operating principle. If you follow the step-by-step instructions, you can make the structure yourself with minimal costs for materials, since improvised means are used during assembly.
Preparation of materials
Before starting assembly, you must ensure that you have the necessary materials:
- insulating tape;
- thermal and superglue;
- battery;
- several bolts;
- bicycle spoke;
- wire made of copper material;
- metal plate;
- nut and washer;
- plywood.
It is necessary to prepare several tools, including pliers, tweezers, a knife, and scissors.
Manufacturing
First, the wire is wound uniformly. It is carefully wound onto a reel. To make the process easier, you can use a base, for example, a rechargeable battery. The winding density should not be high, but light is also not needed.
The resulting coil must be removed from the base. Do this carefully so that the winding is not damaged. This is necessary to make a speed controller for the engine with your own hands. The next step is to remove the insulation at the ends of the wire.
At the next stage, they make a frequency converter for the electric motor with their own hands. The design is simple. A hole is drilled in 5 plates with an electric drill, then they should be put on a bicycle spoke, which is taken as an axle. The plates are pressed, and they are fixed using electrical tape, the excess is cut off using a stationery knife.
When an electric current passes through the coil, the frequency generator creates a magnetic field near itself, which disappears after the electric current is turned off. Taking advantage of this property, one should attract and release metal parts, while turning on and off the electric current.
Manufacturing of current interrupting device
Taking a small plate, attach it to the axis, pressing the structure with pliers for reliability. Next, they make the armature winding of the electric motor with their own hands. To do this, you need to take unvarnished copper wire.
Connect one end of it to a metal plate, installing an axis on its surface. The electric current will pass through the entire structure, consisting of a plate, a metal breaker and an axis. When contacting the breaker, the circuit is closed and opened, which makes it possible to connect an electromagnet and then turn it off.
Making a frame
The frame is necessary, since the electric motor does not allow you to hold this device with your hands. The frame structure is made from plywood.
Making an inductor
2 holes are made in the plywood structure; subsequently, the electric motor coil is secured here with bolts. Such supports perform the following functions:
- anchor support;
- performing the function of an electrical wire.
After connecting the plates, the structure should be pressed with bolts. To ensure that the anchor is secured in a vertical position, a frame is made of a metal bracket. Three holes are drilled in its design: one of them is equal in size to the axis, and two are equal to the diameter of the screws.
Cheek making process
You need to put paper on the nut, and punch a hole on top with a bolt. After putting the paper on the bolt, a washer is placed at the top of it. In total, four such details should be done. The nuts are screwed onto the upper cheek, a washer should be placed underneath and the structure is secured with hot glue. The frame structure is ready.
Next, you need to rewind the wire for electric motors yourself. The end of the wire is wound onto the frame, while twisting the ends of the wire so that the coil is beautiful and presentable. Next, unscrew the nuts and remove the bolt. The beginning and end of the wire are cleaned of varnish, and then the structure is installed on the bolt.
Having made the second coil in a similar way, you need to connect the structure and check how the electric motor works. The bolt head is connected to the positive. You should carry out a smooth start of the electric motor assembled with your own hands.
You should pay close attention to your contacts. Before starting, you should check that they are connected thoroughly. The structure must be glued with superglue. As the current increases, the electric motor power increases.
If the coils are connected in parallel, then the total resistance decreases and the electric current increases. If the structure is connected in series. then the total resistance increases, and the electric current greatly decreases.
Passing through the coil structure, an increase in electric current is observed, which leads to an increase in the size of the magnetic field. In this case, the electric magnet strongly attracts the electric motor armature.
If the design is assembled correctly, the electric motor operates quickly and efficiently. To assemble a model of an electric motor, you do not need any special skills or knowledge.
You can find step-by-step instructions on the Internet with photos at each stage. Taking advantage of this, anyone can quickly assemble an electric motor from scrap materials.
Photos of electric motors with your own hands
Let's consider individual aspects of design. We will not promise the production of a perpetual motion machine, similar to the type of creation attributed to Tesla, but the story is expected to be interesting. We won’t bother readers with paper clips and batteries; we suggest we talk about how to adapt a ready-made motor for your own purposes. It is known that there are a lot of designs, all of them are used, but modern literature leaves the basic principles behind. The authors studied a textbook from the last century, learning how to make an electric motor with their own hands. Now we invite you to plunge into the knowledge that forms the basis of a specialist.
Why are commutator motors often used in everyday life?
If we take the 220V phase, the principle of operation of the electric motor on the collector allows us to produce devices 2-3 times less massive than when using an asynchronous design. This is important when making appliances: hand blenders, mixers, meat grinders. Among other things, it is difficult to accelerate an asynchronous motor above 3000 rpm; for commutator motors there is no such limitation. What makes the devices the only ones suitable for implementing designs of centrifugal juicers, not to mention vacuum cleaners, where the speed is often no lower.
The question of how to make an electric motor speed controller disappears. The problem was solved long ago by cutting off part of the supply voltage sinusoid cycle. This is possible, because it makes no difference to the commutator motor whether it is powered by alternating or direct current. In the first case, the characteristics drop, but the phenomenon is tolerated due to obvious benefits. The commutator type electric motor operates in both the washing machine and the dishwasher. Although the speeds are very different.
It's easy to reverse too. To do this, the polarity of the voltage on one winding changes (if both are touched, the direction of rotation will remain the same). Another problem is how to make an engine with a similar number of components. It is unlikely that you will be able to make the collector yourself, but rewinding it and selecting the stator is quite possible. Note that the rotation speed depends on the number of rotor sections (similar to the amplitude of the supply voltage). But the stator has only a couple of poles.
Finally, when using the specified design, it is possible to create a universal device. The engine runs easily on both alternating and direct current. They simply make a tap on the winding; when switched on, the entire turns are used from the rectified voltage, and when the voltage is sinusoidal, only a part is used. This allows you to save the nominal parameters. Making a primitive commutator-type electric motor does not look like a simple task, but you will be able to completely adapt the parameters to your own needs.
Features of operation of commutator motors
In a brushed motor there are not too many poles on the stator. To be more precise, there are only two - northern and southern. The magnetic field, as opposed to asynchronous motors, does not rotate here. Instead, the position of the poles on the rotor changes. This state of affairs is ensured by the fact that the brushes gradually move along the sections of the copper drum. Special winding of the coils ensures proper distribution. The poles seem to slide around the rotor, pushing it in the desired direction.
To ensure reverse mode, it is enough to change the polarity of the power supply of any winding. The rotor in this case is called the armature, and the stator is called the exciter. These circuits can be connected in parallel to each other or in series. And then the characteristics of the device will begin to change significantly. This is described by mechanical characteristics, take a look at the attached drawing to visualize what is claimed. Here are conditionally shown graphs for two cases:
- When the exciter (stator) and armature (rotor) of a commutator motor are powered in parallel with direct current, its mechanical characteristic is almost horizontal. This means that when the load on the shaft changes, the rated shaft speed is maintained. This is used on processing machines, where changes in speed do not have the best effect on quality. As a result, the part rotates when it is touched by the cutter, as quickly as at the start. If the hindering moment increases too much, the movement stalls. The engine stops. Summary: if you want to use the motor from a vacuum cleaner to create a metalworking (lathe) machine, it is proposed to connect the windings in parallel, because a different type of connection dominates in household appliances. Moreover, the situation is understandable. When the windings are powered in parallel with alternating current, too much inductive reactance is formed. This technique should be used with caution.
- When the rotor and stator are powered in series, the commutator motor has a wonderful property - high torque at the start. This quality is actively used for moving trams, trolleybuses and, probably, electric trains. The main thing is that when the load increases, the speed does not drop. If you start a commutator motor in this mode at idle, the shaft rotation speed will increase immensely. If the power is low - tens of W - there is no need to worry: the friction force of bearings and brushes, an increase in induction currents and the phenomenon of magnetization reversal of the core will together slow down the growth at a specific value. In the case of industrial units or the mentioned vacuum cleaner, when its engine is removed from the housing, the increase in speed occurs like an avalanche. The centrifugal force turns out to be so great that the loads can break the anchor. Be careful when starting commutator motors with series excitation.
Commutator motors with parallel connection of stator and rotor windings are highly adjustable. By introducing a rheostat into the exciter circuit, it is possible to significantly increase the speed. And if you attach one to the armature branch, the rotation, on the contrary, will slow down. This is widely used in technology to achieve the desired characteristics.
The design of a commutator motor and its connection with losses
When designing commutator motors, considerations regarding losses are taken into account. There are three types:
Typically, when powering a commutator motor with alternating current, the windings are connected in series. Otherwise, too much inductive reactance results.
To the above, we add that when a commutator motor is powered by alternating current, the inductive reactance of the windings comes into play. Therefore, at the same effective voltage, the speed will decrease. The stator poles and housing are protected from magnetic losses. The necessity of this can be easily verified by a simple experiment: power a low-power brushed motor from a battery. His body will remain cold. But if you now apply alternating current with the same current value (according to the tester’s readings), the picture will change. Now the housing of the commutator motor will begin to heat up.
Therefore, they even try to assemble the casing from sheets of electrical steel, riveting or gluing using BF-2 and analogues. Finally, let us supplement what has been said with the following statement: the sheets are assembled along a cross section. Often the stator is assembled according to the sketch shown in the figure. In this case, the coil is wound separately according to a template, then insulated and put back on, simplifying assembly. As for the methods, it is easier to cut steel on a plasma machine and not think about the cost of the event.
It’s easier to find (in a landfill, in a garage) a ready-made form for assembly. Then wind coils of copper wire with varnish insulation under it. Obviously the diameter is selected larger. First, the finished coil is pulled onto the first protrusion of the core, then onto the second. Press the wire so that a small air gap remains at the ends. It is believed that this is not critical. To keep it in place, the sharp corners of the two outer plates are cut off, the remaining core is bent outward, pressing the ends of the coil. This will help assemble the engine to factory standards.
Often (especially in blenders) there is an open stator core. This does not distort the shape of the magnetic field. Since there is only one pole, you can’t expect much power. The shape of the core resembles the letter P; a rotor rotates between the legs of the letter in a magnetic field. Circular slots are made in the right places for the device. It is not difficult to assemble such a stator yourself from an old transformer. This is easier than making an electric motor from scratch.
The core at the winding site is insulated with a steel sleeve, and on the sides - with dielectric flanges cut from any suitable plastic.
