How to Use an Electric Motor From a Trimmer

How to Use an Electric Motor From a Trimmer

At one time, when King Hammuram was still living, he argued that time spent on fishing was not included in accounting for the total time of life. This is claimed by many citizens who like to spend part of their free time fishing.

As a rule, most of the 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 on the watery expanses of a large lake, becomes a burden, which requires huge expenses, effort and energy to travel. And here you definitely need a motor: gasoline or electric – no difference.

Nevertheless, special attention should be paid to the electric motor, because:

  • Electric ones do not require oil or gasoline for their work, which means there are no exhaust gases, which does not harm nature;
  • Electric motors are smaller in size, have less weight and do not take up much space. This is especially true if you have to fish far, and every kilogram of excess weight is always felt;
  • They are much more profitable gasoline counterparts in economic terms;
  • Modern designs are assembled on modern parts developed according to modern technologies, therefore, with a minimum weight they have maximum power.

But these statements take place if the owner of the boat already has an electric motor and has experienced these advantages in full. But what if he is not? So, you need to do it yourself.

Electric motor from a drill

Many enterprising boat owners use a drill or screwdriver that runs on batteries, since the principle of operation of an industrial design of an electric motor is based on the same principle. The basic layout of this unit is almost the same for all models and looks as follows:

  • The battery is a power source;
  • An electric motor acts as a boat engine;
  • A propeller with a gearbox is a working tool that provides boat movement on water;
  • Control unit – consists of a handle 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 sealed, which allows the main components to be in the water.

If you use an electric drill, it is desirable that it is located away from water. This is the only problem, quite serious, which requires a technical solution. The slightest ingress of water on the control unit can disable it, which will lead to a boat stop.

Advantages of a similar model

If you take an electric drill, you should always remember that its main value is the engine and the speed control unit (button). The choice of a drill or screwdriver is associated with some advantages, compared with the purchase of an industrial outboard motor:

  • For the price, this purchase will cost 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 in various bodies of water;
  • The electric drill is powered by a battery or other power sources with suitable parameters;
  • The electric drill is easily repairable due to the availability of a sufficient number of spare parts on the market.

Power selection

When choosing a drill, one should take into account the factor that it is mainly intended for cyclic operation. 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 power reserve, otherwise the drill will overheat.

Video: How to Use an Electric Motor From a Trimmer


In such cases, you should opt for power from 150 W and more. The power reserve will allow working with a propeller with a diameter of 130-150 mm. In addition, it must be borne in mind that the total weight of the boat will correspond to 300 kg, not more. We can assume that this is the maximum weight.

Selection of operating voltage

You should immediately pay attention to the fact that drills and screwdrivers are available for various operating voltages, such as 12 V, 14.5 V, 16 V, 18 V and 24 volts. Batteries are also available for the same voltage. And yet, the capacities of standard batteries that serve the operation of an electric drill or screwdriver in classic working conditions are not enough to provide the necessary movement of the boat on the water. In this regard, it is better to pay attention to the car battery, which has a much larger capacity. And since the car battery gives out under a load of 12 V, then the drill should be chosen with a working voltage of 12 V.

Naturally, you can make a battery of batteries from a set of manufactured batteries for electric tools for any voltage, but this can be much more expensive.

Necessary tools and materials

For such an adaptation, the following details will be needed:

  • Electric drill for motor;
  • Clamps for mounting the motor (drill). Both ready-made factory and handicrafts are suitable;
  • The gear from the angle grinder is suitable if the motor is installed on the transom of the boat;
  • Round tubes with a diameter of 20 mm and tubes profiled 20×20 mm. A rod and a mount for the motor (drill) will be made of them;
  • A round rod of metal from which the motor shaft will be made, as well as sheet metal for the propeller.

For work, you may need the following tools:

  • Scissors for metal;
  • Welding machine, although you can do without it;
  • Electric drill and drill set;
  • Angle grinder with cutting and grinding wheels;
  • If the design provides for wood, then nails or self-tapping screws (as well as wood).

Impeller Lift

The presence of a lifting mechanism dramatically simplifies the operation and maintenance of the entire system, especially since there are cases when you need to urgently raise the propeller. As a rule, a similar mechanism controls the position of the electric motor in all planes (vertical and horizontal).

Alternatively, you can offer the following design of such a mechanism: a motor is mounted on the boat transom with clamps that are rigidly fixed to the plate. The clamps are equipped with rings through which the tube is threaded, and a motor shaft is threaded to the axis welded to the center of the tube. It turns out a very simple swivel that can provide normal motor control.

Gearbox mounting and propeller manufacturing

As far as is known, the drill is designed for drilling holes and has high final revolutions, which is not acceptable to ensure the operation of the propeller, which operates at slower revolutions. Therefore, to reduce the speed transmitted to the screw, the installation of a gearbox is required. Sometimes they need 2 pieces, depending on the design decisions. The upper gearbox should lower the speed of the drill from 1500 to 200-300 revolutions, which will ensure the normal course of the boat.

The lower gearbox is used for horizontal installation of the propeller. When using a gear from an angle grinder, it is simply clamped in the drill chuck.

The manufacture of a propeller propeller begins with marking it on a piece of steel sheet. As already mentioned above, its diameter should be no more than 130-150 mm. You can take a square of metal, with dimensions of 200×200 mm and a thickness of 2.5-3.0 mm. It is better if it is stainless steel, although it is much more difficult to process. In extreme cases, you can use the impeller from an air exhaust fan or a car cooling system. In this case, it should be borne in mind that the impeller profile is designed to work with air mass. In this regard, it is necessary to do its own production.

A hole for the landing screw is drilled in the center of the square. Slots are made along the diagonals so that in the center the sheet remains intact up to 25-30 mm. After this, they begin to form the shape of the blades. As a rule, they have a rounded appearance. In this case, it is necessary to ensure that the blades have the same size, otherwise there will be vibrations. After this, the blades are slightly turned at a certain angle. In this case, you need to consider the direction of rotation of the blade.

Design test prior to installation on a boat

Since the manufacture takes place at home and, as they say, does not break off on the water, tests should be carried out. For this, any water tank in which the propeller fits will fit. Naturally, the larger the capacity, the better. In extreme cases, if possible, it is recommended to go into nature, to a river or pond and try it out 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, serious vibrations should not be felt. If the propeller does not work at full power, you can modify it by increasing the angle of inclination of the blades.

The engine management system is being finalized depending on the wishes of the boat owner. The main thing is to manage it was convenient. It is better to move the engine speed control button to a convenient place.