Ah… the Flex-o-Fold, three bladed folding prop.
First off… If you’re in San Diego or coming to San Diego for a haul out, we highly recommend Shelter Island Boat Yard for all your haul out needs. They run an amazing business, stand behind their work and most importantly, are fair with their prices. We’ve used SIBY for over 10 years and recommend them to everybody. Contact Wayne or Scott at 619-222-0481.
Flexofold recommended a 22” prop as a replacement and that’s what we went with.
To get the flexofold to fit, you have to cut approximately ¾-1” of your shaft off. This is the part that normally holds the cotter pin for your fixed blade prop. It has to be cut off to allow room for the blades to fold.
Original prop
There is still room to use the 2 large nuts should you need to put your old prop back on… but you wouldn’t be able to use a cotter pin. This is a sacrifice you have to make.
This is a picture of everything that comes with the prop.
Unpacked. All components included.
After putting the prop on, at 1900 rpm, I think we’re picking up about a ½ kt based upon the same rpm as the old prop.
Flexofold hub
With the old prop, we were only able to get about 3000 rpm and I notice with the new prop, we get about 2900 rpm max, but at that rpm, the boat is flying at over 9.5 kts… so I think I’m ok with the fewer turns.
I notice with the new prop it takes more rpm’s to get the boat to slow down or stop… but with that, there’s noticeably much less prop walk. So it’s a trade off…. Not quite the reverse performance of the old prop…. But much easier to back in a straight line.
Look how little drag is induced when the blades are folded. Not much left to grab on to seaweed or floating line.
Flexofold prop, folded
The real results will be when we get it sailing… and hopefully pointing just a little bit higher when close hauled.
An update.
We did a quick 7 day trip offshore. We were only able to get about 2800 RPM on the prop. That’s fully 400 below the max WOT (Wide open throttle) of 3200.
We consulted our vendor and they agreed that we had too big of a prop installed.
They coordinated new blades from Flex-o-fold, which were installed while in the slip. The diver simply removed the old blades and installed new 20″ 14-3R blades. Easy-peasy
Flex o fold blade 20″ 14-3R
Happy to report that we can now make the 3200 RPMs recommended by Yanmar.
Before you get worried… we usually cruise a little less than the 80% of WOT, recommended by Yanmar.
While I’m told by Yanmar that these engines need to be run hard… near 80% WOT which equals about 2550…. we run about 2200 and occasionally open the throttle to 2500.
This folding propeller is an absolute thing of beauty.
Flexofold open
Also, we’ve noticed we’re able to point higher…. comfortably near 45-50° off the wind. A huge improvement while sailing! The higher sailing performance and the marked increase in speed are one of the best improvements we’ve done to Volare.
Finally, a picture of the collar zinc. Check out the cool props here;
Collar zinc
Thanks for reading! Make sure to check out the rest of our website and follow along with our travels at CruisingVolare.