Prop

[neil brand]

I ahve a 1990 catalina 28. It has a 3 blade prop that was added by the previous owner. I also have the original 2 blade prop. Can anyone advise as to the advantages or disadvantages of 2 vs 3 blade. I am inclined to go back to 2 blades asI think it would sail better.Any input is appreciated.neil Brand

 

[Ron]

2 vs 3 blade

NeilA three-blade generally gives you more thrust, since the thrust realized is proportional to the total surface area of the blades (other factors being equal). A two-blade has less surface area to create drag.If you are a performance zealot (e.g., do racing), a folding two-blade is probably the way to go. If you are a cruiser, and (like many of us) you don't have all the time in the world to get somewhere, you'll do a fair amount under power and the three-blade becomes attractive.Just make sure that either prop is appropriately sized for your boat (prop diameter) and for the engine/transmission combo (prop pitch).--Ron

 

[Dennis Thomas]

Also, 3 blade = less vibration

Lot's of good treads in the archives on this subject.