2 blades propeller

[Hisham]

Dear All

i am about to start building my first wooden pontoon pedal boat

i know that for pedal propulsion, it is more efficient to use 2 blades propeller

i need a supplier for this type of propellers or
a drawings to make it from wood

help plz????

[FAST FRED]

If you can stand the larger diameter a single blade prop (with small counterweight) is even more efficent.

This was done on small aircraft 60 years ago, and works to reduce induced prop drag.

FF

[Çemberci]

sir
ıf you give us propeller size i will draw your propeller
oktay çemberci

[Guest625101138]

Originally Posted by Hisham

Dear All

i am about to start building my first wooden pontoon pedal boat

i know that for pedal propulsion, it is more efficient to use 2 blades propeller

i need a supplier for this type of propellers or
a drawings to make it from wood

help plz????

You need to know:
The power level you intend to operate at - 80W average person, 120 trained older person, 150W trained middle age person, 200W trained young adult, 250W athletic male, 500W olympic athlete for 5 minutes or average adult for 20 seconds.

Cadence for the nominated power. 60rpm is leisurely, 80 rpm is energetic, 90rpm is peleton, 120rpm is typically maximum power, 140rpm (with 175mm cranks) is around rev limit, can spin faster with smaller cranks, well trained athlete can spin to maybe 200rpm.

The total displacement.

The hull shape so drag versus speed can be determined.

The drive system so gear ratio is known.

Once you have all this I can design an optimum prop that you can fabricate or find something close from a model maker or small boat shop.

Rick W.