2 blade or 3 blade

[lumphammer]

I'm looking into a new folding prop for my Moody 36. I have pretty much decided on the flex-o-fold following various positive comments on this forum.

I contacted the parent company in Denmark and they recommended a 2-blade prop. I have always assumed that I would need three blades, but looking at the Yachting Monthly review of folding/feathering props there seems very little to choose between a 2B or 3B flex-o-fold.

The advantages of the 2-blader seem to be lower cost, less complex mechanics and a neater folded shape. Is there any reason I should be considering a 3-blader instead?

TIA

 

[Seajet]

I can't see anyone arguing with the fact 3 blades should transmit more power, but she's primarily a sailing boat, not a tug !

I agree the 3 blade folders are a lot more intricate, and while lovely ( very expensive ) bits of engineering there has to be more to go wrong.

It's really a matter of how & where you sail, how much do you need maximum from your engine ?

 

[billmacfarlane]

I spoke to Darglow about buying a Flexofold at SBS, and asked what were the differences between the 2 and 3 blade.The reply was that, on a flat sea, the difference in speed at the same revs would be minimal, but on motoring through a chop the 3 blade prop would give you better speed. I bought a 3 bladed version. Can't tell you much about its performance yet as I'm not due to be launched until the start of March.

 

[johnalison]

It is generally accepted that with the Volvo folding props you should get the same speed with the 3-bladed prop at 400 fewer rpm . I have a 2-bladed and the performance is adequate in most conditions.