I would like to replace my prop with a folding prop. The c&c manual recommends a 10 pitch. Has anyone replaced with a larger pitch? Any issues that I should be concerned about?
Thanks
Thanks
C&C 30Mkii Folding Prop
- Thread starter true love
- Start date
The prop manufacturer will be able to tell you the best size based on your engine and transmission. Depending on the geometry of your prop shaft you may be limited on maximum diameter, to make sure the blades aren’t too close to the hull. You’ll want at least an inch or two of separation there. The rule of thumb is that the space should be at least 10% of the length of the blades.
The only other thing to keep in mind is that some folding props (Flexofold in particular) fold with the blades back, so you’ll want to make sure you have clearance behind the hub without touching the rudder.
The only other thing to keep in mind is that some folding props (Flexofold in particular) fold with the blades back, so you’ll want to make sure you have clearance behind the hub without touching the rudder.
Lots of options, so best to talk to the various prop mfg’s to get their recommendation…
I did this myself last winter…many things to think about…
- Folding or feathering... I ended up with a feathering Max Prop from PYI…
- 2 or 3 blades…I really wanted a 3 blade to try and reduce vibration…
One deciding factor for me was the fact that the Max Prop pitch is adjustable….so even if we guess wrong, it can be adjusted and tweaked.
As it turns out, the guidance from PYI for my 3-blade was pretty darn close. She has excellent reverse bite…a big plus for the Max Prop, and her forward bit is good. I may adjust the pitch over the winter a little and try to dial it in a bit more for the forward pitch.
PYI took my boat info (displacement, length, beam, etc.) and my engine / tranny info (HP, # of cylinders, gear reduction) and made the recommendation for both a 2-blade and 3-blade feathering prop. I also gave the info to Flex-o-Fold which is another prop I considered. They gave me their recommendations on prop size and pitch. But unlike the Max Prop, the FoF pitch cannot be adjusted.
I feel that the feathering prop (at least the MaxProp) is better at providing power in the water (especially in reverse) than the folding props. But the folding props are probably a little more streamlined in the water. Just my take…no empirical data to back it up…
So far though, I am very happy with my 3-blade Max Prop. And they really are a thing of beauty..
Greg
I did this myself last winter…many things to think about…
- Folding or feathering... I ended up with a feathering Max Prop from PYI…
- 2 or 3 blades…I really wanted a 3 blade to try and reduce vibration…
One deciding factor for me was the fact that the Max Prop pitch is adjustable….so even if we guess wrong, it can be adjusted and tweaked.
As it turns out, the guidance from PYI for my 3-blade was pretty darn close. She has excellent reverse bite…a big plus for the Max Prop, and her forward bit is good. I may adjust the pitch over the winter a little and try to dial it in a bit more for the forward pitch.
PYI took my boat info (displacement, length, beam, etc.) and my engine / tranny info (HP, # of cylinders, gear reduction) and made the recommendation for both a 2-blade and 3-blade feathering prop. I also gave the info to Flex-o-Fold which is another prop I considered. They gave me their recommendations on prop size and pitch. But unlike the Max Prop, the FoF pitch cannot be adjusted.
I feel that the feathering prop (at least the MaxProp) is better at providing power in the water (especially in reverse) than the folding props. But the folding props are probably a little more streamlined in the water. Just my take…no empirical data to back it up…
So far though, I am very happy with my 3-blade Max Prop. And they really are a thing of beauty..
Greg
Your sense is pretty close, at least according to Yachting Monthly’s tests on the subject. They show folding props slightly better in forward and when sailing, but feathering decidedly better in reverse.
Folding and feathering propeller test
Which is the best folding or feathering propeller for you? Emrhys Barrell compares 15 props in a test of speed, thrust, drag, stopping speed and propwalk
www.yachtingmonthly.com
(I for one am very happy with my 3 blade Flexofold, but plenty of people are equally happy with their feathering props.)
