The Boat propeller combines many important functions in a boat. It combines the functions of transmission, wheels and tires when equated with a car. Boat prop balancing is very important to extend the life of the propeller and the engine and to cut down the noise of the engine.
To balance a boat prop, one needs leather gloves, goggles, a respirator, modeling clay, a good boat propeller balancer, metal file, a green carbide wheel, fine sandpaper or sanding drum, 320 grit sandpaper, block of wood, stroboscope, oiled sandpaper and propeller polishing compound.
The first step in boat prop balancing is to protect oneself before starting the process. Gloves, goggles and a respirator should be worn.
The second step is to correct the dimensional balance of the propeller. This is done by making the blades of the propellers the same size. To do this the blades should be pressed into modeling clay to get a mold of the exact size. Using a metal file or a carbide wheel all the blades should be filed to fit the mold. After the correct size is achieved, the edge should be made smooth using a sanding drum or sandpaper. A smooth angle should lead to the trail edge of the blade.
The next step in boat prop balancing is to achieve static balancing of the propeller. For accurate results, a propeller balancer should be used. Static balancing is making sure that all the blades are of the same weight. If one blade is thicker than the other, thickness should be removed by using a hard block of wood and 320 grit sandpaper. The thickness of the blade from the top to bottom should also be the same. Placing blades side by side on the prop balancer will give an indication as to which blade is thicker. The thicker blade will come down the side of the balance.
The spin balance should be corrected as a next step. The prop should be placed on the balance with a stroboscope. The prop should be spun to see if there are any irregularities in the spinning cycle. Heavier blades will be on the outer side of the wobble and this will indicate that the spinning is not balanced. Reducing the weight of the blade to match the others using oiled sandpaper till it is smooth will correct the spinning balance of a prop. Repeat the spinning till there is no wobble and the prop spins correctly in a circle.
The last step in boat prop balancing is to polish the prop. The prop should be polished to a high shine using a good wax based polishing compound. This will increase its water resistance and will remove any grit or metal bits left by the process of filing and sanding. They also have a smoother surface after a coat or two of polish when they grip the water.
Boat prop balancing should be periodically performed to improve performance and for reducing the wear and tear of the equipment. A well balanced boat prop is absolutely essential for racing or speed boating.
