The Truth about Boat Propellers. Part 1 - Composite Propellers.

The Truth about Boat Propellers. Part 1 - Composite Propellers.

Composite is not better than aluminum

There is a myth about composite propellers. After being a serious boater for over 15 years and haven run and tested hundreds of props on many different boats, I've learned a few things about props.

There is a myth about composite propellers: "Composite propellers run better that aluminum props and almost as good as stainless steel propellers." If you believe that one, I have some snake oil to sell you.

First I will start with the fact that different aluminum props from various manufacturers will have a major difference in overall performance between the best prop and the worst prop. On a good day a composite propeller will perform as well as the worst aluminum prop.

It is simply the fact that there has not been a composite propeller manufacturer that has designed a propeller that performs well. These composite props lack in rake, cupping, pitch progression and blade area. Many boaters claim that their composite prop runs better than their aluminum. However, most of these boaters replaced 3-blade aluminum prop with 4 blade composite. For some boat uses a 4 blade prop is better than a 3 blade. I'll get into that in another section. Some of these claim of better composite performance is because they were propped wrong with their aluminum and finally bought the right pitch in composite.

Many composite propellers use a gimic in their design. One manufacturer has removable blades, another has a variable pitch adjustment, and others try to sell their props the old fashioned way.

The real way to understand the composite performance myth is to put it to the test yourself. But do it right, compare apples to apples. Take the best known performing composite prop you know of and pin it against a leading aluminum prop. If you're looking at an aftermarket aluminum propeller, Turning Point Propellers' Hustler prop is the best. Or in the original equipment side of it, run a Mercury prop. They make them to fit all applications, just like Turning Point. Put it to the test and you'll understand what I'm talking about.

Check back soon as I'll comment on other areas on boat propellers.

Peter Sagartz
eBuyersWorld.com