How to Make a Homemade Outboard Trimmer Motor
Remaking an ordinary boat, even a rubber one, into a motorboat is as easy as shelling pears: you need to install a gas engine on it. Electric is not appreciated by our fishermen: a heavy, small power reserve and there is no way to recharge it during long fishing. However, the cost of even the simplest option for a boat is pretty good. 20-30 thousand rubles.
Making a homemade outboard motor
Trimmer motor: features
The idea to use as a boat engine from something else came up with more than one home master. As a result, we learned how to make a motor for a boat from a lawn mower, a screwdriver, and, of course, lawn mowers. Of course. Because the cost of lawn mowing compared to the motor is an order of magnitude lower, and the drive power is quite acceptable.
The motor from the trimmer is easiest to make, since the device has all the necessary mechanisms:
- Economical engine. Especially when it comes to four-stroke. In most cases, of course, push-pull is used, since its cost is lower;
- Built-in fuel tank, almost always transparent, so that the fuel level is easily controlled;
- Ready-made controls. Starter, gas;
- A shaft with a rigid shaft that transmits torque.
The only difficulty when reinstalling the motor is the different tasks for which the engines were developed. The lawnmowing drive operates at high speeds and low torque, while the boat drive must do the opposite. Therefore, to build an outboard motor from the trimmer, you will need both tools and drawings. In the photo. An example of using lawn mowers as a drive.
Necessary tools and materials
- Trimmer. An apparatus with a power of 0.7–0.8 kW is sufficient for a small rubber boat. According to users, even with such a drive, the boat moves at a speed of 5-7 km / h. For steel, more powerful drives are used. At the same time, the weight of the machine must also be taken into account.
- Duralumin for screw, thickness 2 mm.
- A clamp or other device in order to secure the engine to the boat.
- Welding machine. You can do without it only if all the necessary parts are purchased.
Manufacturing technology
Outboard motors from the trimmer are made in two ways: all parts, like a screw, are bought or made with your own hands. The second solution will require more effort, but also less cost.
As such, the drawing is not needed for the drive itself, but in the manufacture of a makeshift screw. The dimensions of the latter depend on the power of the drive and the mass of the boat. A screw with parameters of 10030 mm is quite capable of moving vehicles weighing up to 120 kg.
- It’s easier and faster to build a motor for the boat from the trimmer, if you choose a model with a straight shaft. If a device with a curved shaft is used. A rod with a curved shape, it will have to be completely redone, since a steel cable, in principle, cannot transmit delivery torque. In this case, the tube will need to be made by hand from duralumin, then press the bronze sleeve remaining after disassembling the bent shaft into it and reinsert the fitted plastic holder.
- A homemade screw is cut from a duralumin plate according to the drawing, the edges are sharpened. The blade should have a curved shape, for this they are in turn bent 10 mm. The screw can always be corrected by cutting or bending stronger than the blade if its operation during the tests is unsatisfactory.
- The screw is installed instead of the trimmer head. The use of an annular nozzle is mandatory, otherwise the blades can break through the boat material or damage it. In the photo. Screw mounting.
- Through the Internet, you can find ready-made kits for converting lawn mowers into a craft. It includes a drive and adapters to the shaft. The adapters are universal, which allows you to do without alterations of the curved rod and shaft. Often a clamp is included in such a kit. In this case, all the work comes down to assembling the modification.
- Management. The starter handle, can be used from the trimmer. But if it is inconvenient, which is often the case, it is replaced with any suitable switch. From a bicycle, for example.
- Home-made boat motors from the trimmer are fixed with a clamp on the boat transom.
In the, the process of converting lawn mowers into a boat drive is discussed in more detail.