packyj

I'm finishing up my extra 330 and was hoping to get some info on going with a 3 blade prop for that nice scale look... the suggested prop is 10x4.7 i believe... was hoping to find some kind of general guideline as to where to start from and also what benefits/detriments i can expect

jdetray

From what I have read, the main benefit of switching to a 3-blade prop is scale appearance. And the fact that on some planes, the smaller diameter of the 3-blade prop is necessary for ground clearance. With a 2-blade prop, the landing gear for some planes would need to be ridiculously long.

The 3-blade prop will often be less efficient than a 2-blade prop of the same design. Single-blade props are said to be even more efficient than 2-blade props and are actually used on some control-line planes!

Here are some threads on this topic, perhaps more than you ever wanted to know:

[link=http://www.rcgroups.com/forums/showthread.php?t=217989]three blade prop[/link]
[link=http://www.rcgroups.com/forums/showthread.php?t=189013]2 vs 3 blade props[/link]
[link=http://www.rcgroups.com/forums/showthread.php?t=547311]2- and 3-blade props[/link]
[link=http://www.rcgroups.com/forums/showthread.php?t=291277]Three bladed r/c prop?[/link]

- Jeff

P.S. -- I think the rule of thumb is to reduce prop diameter by one inch for each blade you add.

packyj

many thx jde. that was exactly the information I was looking for... now to figure out how to mount it to my brushless :P