What is Boat Propeller Balance?

How do you know if a boat propeller is out of balance?

As a boater, you may notice you’re having vibration. Here at Tacoma Propeller, we’ll check. Even if you don’t feel or hear vibration while boating, your boat propeller could still be out of balance. Balancing is a part of every boat propeller repair we perform.

What does boat propeller balance mean?

A balanced propeller will have its weight evenly distributed around its blades, so none are heavier than the other which makes for smooth propulsion. There are four basic types of propeller balance: Static, Kinetic, Dynamic and Whip. Marine propellers are balanced using Static or Dynamic methods. Tacoma Propeller uses the static balance method. Typically, propellers that are dynamically balanced still need to be followed with a static balance.

• Dynamic balancing has its place specifically with vessels operating at higher accuracy using Class S propellers. Using this method, if weights were placed 180 degrees opposite the other on a propeller, a twist would be caused by the weights on the two separate planes. If in balance, no single point would roll to the bottom. By rotating the propeller at an appreciable speed each weight would cause its own centrifugal force on separate planes, causing an end-to-end rocking motion.
• Static balancing of a boat propeller is very important. After grinding the welds down and shaping the blade to the desired specifications, balancing is the final step in the physical boat propeller repair before the cosmetic finish. Static balancing puts gravity to work. To achieve a balanced propeller, we mount the propeller on the balancing arbor which is placed between centers on frictionless rollers on a balancing fixture. If the prop is out of balance, the heavy blade or blades will swing down to the bottom immediately. This is corrected by adding or removing weight from the propeller. Our prop technicians then remove excess weight on the heavy blade or blades, using a grinder on the forward face of the propeller with care to avoid grinding the edges. This process is repeated until all blades remain still-regardless of what position the prop is turned.

Why does my boat propeller need to be balanced?

As we mentioned previously if you’ve noticed vibration your boat prop is probably out of balance. Running a well-conditioned boat propeller will help you have a smooth comfortable boating experience.  An out-of-balance propeller with noisy and uncomfortable vibration can lead to excessive bearing wear, which can also lead to shaft damage.