Curious what everyone’s thoughts or experiences have been regarding folding props versus 3 blade. Tessa came with a folding prop and I get that there is less drag, but how much really? I will need to decide soon for my new engine.
Rebecca Bray
“Tessa” N30C #11
Watch Hill, RI
If you are racing, get a folding prop. If you are just day sailing for fun, a fixed prop will do. If you are cruising over longer distances and sailing 15-30 miles per day… then while sailing a folding prop will increase your boat speed by about 0.5-1.0 knots.
Don
Rebecca,
Soave has a fixed 3-blade prop. My PHRF cert gave me 12 seconds per mile for it.
With 4 knots as an average speed… that’s 15 mins per mile
With 4.5 knots as an average speed… that’s 13.3 mins per mile
The difference between 15-13.3 is 1.7 mins or 102 seconds.
I’m hoping folks who get a .5 knot advantage from their folding prop will talk to the phrf handicapper for YRALIS….. because the handicapper says 12 seconds per mile. I got jipped !
The reason why serious racers use the folding props is because having a relatively minor speed advantage opens the door to establish tactical advantages over similarly rated boats.
Folding props have some quirks in reverse, but most folks get used to the quirks.
Once I master sailing Soave, if I continue to race, I’ll probably upgrade. For now I’m still learning plenty with my fixed prop.
Rob….
This is the best prop analysis I have seen. I am a fan of Flexofold. They are good folks to deal with. You also get a lot less propwalk . Only downside is price but folders are cheaper than featherers
https://www.yachtingmonthly.com/gear/folding-and-feathering-propeller-test-29807
Bruce Clark. N30, Nonsuch, Whitby YC, Lake Ontario
I use a 3 blade Campbell Sailer prop. Fixed blades that are skinny and cupped. Very low drag, lots of power and never wears out. I put one on my previous boat as well.
Dave DeWolfe
NS26C #150 Ascension
Marriotts Cove NS
I changed my fixed three-blade for a Kiwi feathering, composite prop. In winds up to about 10 kts it added 1 kt to boat speed. It has less prop walk and reverses well. Three of us at the RCYC in Toronto have the Kiwi prop. It is far less expensive than Flexfold and other alteratives.
Nicholas Hirst
Mirthin N30U #513
RCYC Toronto
Maybe edit your post to say if you have a saildrive or prop shaft.
My boat came with a new Volvo Penta d1-30 and VP saildrive. The 3 blade folding is also VP. It reverses extremely well including backing out of the slip and going into reverse to slow the bot when entering the slip. Very responsive. If you have a shaft, this will mean nothing to you.
Chris
NS 30C 1980 1sail 101.
Lake Ontario
Years ago we had an impromptu race at one of our rendezvous. La Reina had a two blade feathering max prop. A 30U had a three blade fixed prop. We both had six people aboard. The 30 had one of the best , if not the best Nonsuch sailors in our area aboard. It was about my 4th year os sailing La Reina. After about 5 miles of a beam reaching the 30 was so far behind the owner was almost in tears. They slipped the transmission into neutral and let it spin (it was okay for his transmission) and his performance improved considerably. If you like sailing rather than motoring I recommend you get a feathering or folding prop. Feathering generally respond faster in reverse than a folder but they are more money and require more maintenance. My Max prop lasted about 38 years but I hauled and serviced it every year. The Kiwi prop has the same pitch in forward as in reverse but most transmissions are 1:1 in reverse but 2:1 or 2.5:1 in forward so if the Kiwi is properly pitched for forward it is over pitched for reverse. Engines 20 hp and under generally struggle in reverse with a Kiwi prop. One solution for the Kiwi prop is to use self tapping screws as stops to limit the amount the prop opens in reverse. This seems to help. The blades on the Kiwi prop are nice and light so generally less vibration, they are less prone to fouling and galvanic corrosion is not real an issue with them. Historically if you wanted to start a fight in a sailor’s pub you asked which was the best prop or anchor.
Mark Powers
I didn’t find that having my fixed three-blade in neutral helped. It was just a drag - in all senses. I do not find any problem in reverse but I do not believe although I am not sure that the V transmission with my Yanmar engine has different pitches. The Kiwi has so improved my sailing that I will fight for it in a sailors’ bar. You do have to remember to clear the weeds, though.
Best,
NIck
Nicholas Hirst
nicholashirst@me.com
Mirthin N30U #513
RCYC, Toronto
Bruce’s article is the best I found as well. I had a first generation, 2 bladed, feathering, MaxProp that was in need of a rebuild. I repowered with a Beta 25, not a saildrive. I upgraded to the 3 bladed, 15 inch, feathering, Max Prop. PYI recommended that prop, the size and set the pitch before they shipped it. I sent the data to Beta and they agreed it was a good fit.
As far as performance is concerned, The 2 bladed Maxprop was like dropping anchor when I put it in reverse. The 3 blade has slightly less stopping power in reverse. It took about 3 times approaching the dock to adjust, but it is minimal. The 3 blade has a little less prop walk to port in reverse. I don’t race, at least, not on my boat. I have owned the boat for 5 years and have never had a fixed prop on it. So I cannot give you a measurement of lessoning drag advantage. Again, read that article. It is very informative. I am sure it was not cheap to perform the experiment.
I am very happy with the combined performance of the two. We can carry on a conversation while motoring without raising our voices.
Chuck Garbarino
As You Wish
N30U #292
Sodus Point, NY
I installed a new Beta 35 engine this year with a fixed pitch 3 blade propeller. It has not had any adverse impact on the sailing of my boat. These are cat boats with an extreme beam to length ratio so they weren’t designed to go fast and going a little slower by .1 knots, isn’t really a penalty in my opinion.
Our boat came with a Gori 3-blade 2-pitch reversible folding prop. It works well but it’s a pain. The idea is that the leading edge is always the leading edge in forward and reverse. The dual pitch bit is that it can be reversed: trailing edge first for a higher pitch. That is achieved by folding and opening the prop, if moving then to neutral then back in gear. The pain comes from the 50:50 chance of being in the preferred normal pitch is <<50%, by Murphy’s law. Nice idea, a pain in practice.