Carbon Props?

Take a look at Volante's page. Good info here. It's not hype. A number of yacht builder's have adapted. Many years ago, I conducted extensive research into reflex impeller and stator blades for the Navy. The benefits are numerous...

http://www.compositecarbonfiberprop.com/

Beyond the obvious, i.e., replaceable blades, reduced weight, reduced vibration, anti-fouling properties... if the right prop is chosen for load and RPM (and it is properly designed) it will offer performance and efficiency gains. This is a by-product of blade flex, not reduced cross section or less weight.

There are *true* carbon fiber props. I can't comment on the impact resistance of these props. No experience with 'em.

Then, there are nylon re-inforced graphite composites that generally offer good impact resistance and increased blade flex. Again, if the right blade thickness, shape, sectioning and durometer are chosen, these props have merit. Their application isn't for every craft. They may be well-suited for yachts, based on the speed and RPM's used in this environment, but they're not the right choice for hi-speed, surfacing apps.

Any captains/owners running these props?

I am curious about real world experience with them, as we are reproping the boat.

nas

Hi,

Take a look here,

http://www.engineeringnews.co.za/eng/views/columnist/develop/?show=63801

If you google some of the trade names you will get further information

Hi I would like to see if anyone has now had experience with carbon props and their remarks?

Also why are they not suitable for high performance surface use?

Thanks!

I do not know for certain why carbon fiber props cannot be used in surface drives. When surface drives were in their infancy the loading and unloading of the propeller blades caused them to frequently crack. They combated this by using a straight leading edge that is a bit thicker than conventional propellers. I would figure that because carbon fiber blades are even stiffer this repeated stress would cause them to crack as well.

I nixed the carbon fiber propellers for the last boat I ran based on cost and lack of data. For the price of carbon propellers I could by two sets of conventional props.

One other thing to consider if you hit bottom and break off all the blades on carbon fiber propellers you will lose propulsion. On conventional propellers it should be harder to completely destroy all of the blades and you will be able to limp home.

nas

I was in a conversation not to long ago with a captain who was telling me that he was running a 120ft boat with carb props. He said it felt like the pitch would staighten out under load or that the pitch was wrong all together. Basically he thought his experience with the props was not very good.

I thought I read somewhere that de-lamination occured on C.F props in highspeed applications from cavitiation...didn't the guys on Earth Racer have this problem and had to replace a prop? Does anyone make them out of S-glass instead?

Been a long time since this subject was first brought up,....and then it seems to have died off rather quickly??

Any new experiences over these last few years??

I was just looking here:
Contur® Carbon Fiber Propeller Technology

Ring Thruster Propulsion Units

...And how about this other product of their's .....any personal experiences??


Carbon Fiber Ring Thruster Propulsion System

I've heard that they flex and lose pitch under high load/rpm situations

This all very fascinating! great use of materials, Carbon Fiber props better used on smaller crafts?

Prop materials

Performance Propellers (don't know if they still exist) made sailboat props out of urethane with claims of improved performance under all conditions.

The other side of that scenario is if the carbon props are the type with replaceable blades it is simple and quick to remove the stubs, install new blades in the water at the scene of the embarrassment and continue on with the voyage. No limping required.