Rudder Fairing
Moderator: Jim Walsh
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Rudder Fairing
When I installed the Beta engine in the Far Reach a couple years ago I also flush mounted the four through-hulls. The only project left to make the underwater profile as smooth and fair as possible is to fair the trailing edge of the rudder from its fat 5/8" rounded profile to a narrower squared off edge.
Yesterday, I used a porter cable DA 5" sander with 60 grit to sand down the profile to a smooth 3/16" squares off edge. This is supposed to be the most efficient trailing edge profile for rudders.
I still need to fair in a few spots before I cover with barrier coat and the bottom paint. At that point I think I have done all I can do to make the underwater profile as smooth as possible to reduce underwater drag and unwanted turbulence. I plan to stay with ablative paint for now.
I also include a photo of the prop shaft log I installed during the engine built. You will see on the trailing edge I also added a small streamlined squared off edge there too.
Yesterday, I used a porter cable DA 5" sander with 60 grit to sand down the profile to a smooth 3/16" squares off edge. This is supposed to be the most efficient trailing edge profile for rudders.
I still need to fair in a few spots before I cover with barrier coat and the bottom paint. At that point I think I have done all I can do to make the underwater profile as smooth as possible to reduce underwater drag and unwanted turbulence. I plan to stay with ablative paint for now.
I also include a photo of the prop shaft log I installed during the engine built. You will see on the trailing edge I also added a small streamlined squared off edge there too.
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- Joined: Feb 8th, '17, 14:23
- Location: s/v "Leoma" 1977 CD 30K #46 San Francisco CA
Re: Rudder Fairing
Hi John. You do such nice work. Way over my head. I better learn how to sail first before I think about all that. I’m at Bahía Assunciun now taking my time visiting some of the places I missed. I need to pass some time I dont want to leave Mexico till April. I met an old (79} Guy sailed from Japan to Aleutians and down here. We are sailing together then he goes south and I go northwest. He keeps catching fish. Tried to get me to eat sushi Bonita and boiled fish head soup. No Way. I fried fish last night
WDM3579
MMSI 368198510
MMSI 368198510
Re: Rudder Fairing
It’s not just a vanity project as some might assume. Fair surfaces really do result in speed improvements. I faired my rudder several years ago and although it’s a pain in the neck it made me feel better even if the increase in performance was negligible. I retained the original trailing edge but I now have a smooth airfoil devoid of a series of high and low spots.
Jim Walsh
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
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- Posts: 3582
- Joined: Oct 6th, '08, 07:30
- Location: S/V Far Reach: CD 36 #61 www.farreachvoayges.net www.farreachvoyages.com
Re: Rudder Fairing
Oh I think you have done some great work yourself JD...and you're out there sailing. Even better.JD-MDR wrote: ↑Mar 18th, '24, 15:07 Hi John. You do such nice work. Way over my head. I better learn how to sail first before I think about all that. I’m at Bahía Assunciun now taking my time visiting some of the places I missed. I need to pass some time I dont want to leave Mexico till April. I met an old (79} Guy sailed from Japan to Aleutians and down here. We are sailing together then he goes south and I go northwest. He keeps catching fish. Tried to get me to eat sushi Bonita and boiled fish head soup. No Way. I fried fish last night
Sushi...yum.
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Re: Rudder Fairing
I don't think it's vane in wanting your boat to perform as well as it can just because it brings you pleasure. When the FR is sailing fast and balanced it puts a smile on my face. If somebody thinks we are being vane they are justifying their own laziness...which is different than someone who just doesn't think the juice is worth the squeeze. The first is lame and the second I can sympathize with.Jim Walsh wrote: ↑Mar 18th, '24, 16:14 It’s not just a vanity project as some might assume. Fair surfaces really do result in speed improvements. I faired my rudder several years ago and although it’s a pain in the neck it made me feel better even if the increase in performance was negligible. I retained the original trailing edge but I now have a smooth airfoil devoid of a series of high and low spots.
My rudder is probably not as streamlined and perfectly fair as it could be. But I think getting the trailing edge right will sure help.
Last edited by John Stone on Mar 21st, '24, 13:51, edited 1 time in total.
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- Joined: Feb 8th, '17, 14:23
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Re: Rudder Fairing
I wonder if fairing the trailing edge is the same principle as for the propeller. Since I installed the new engine and propeller I have a horrible screeching noise. Ive been told it’s called prop singing and I need to fair down the trailing edge.
WDM3579
MMSI 368198510
MMSI 368198510
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- Posts: 3582
- Joined: Oct 6th, '08, 07:30
- Location: S/V Far Reach: CD 36 #61 www.farreachvoayges.net www.farreachvoyages.com
Re: Rudder Fairing
I have never heard of that JD. I defer to others with more engine experience.
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- Posts: 877
- Joined: Feb 8th, '17, 14:23
- Location: s/v "Leoma" 1977 CD 30K #46 San Francisco CA
Re: Rudder Fairing
I’ve heard but never experienced it. It comes and goes at different rom’s
WDM3579
MMSI 368198510
MMSI 368198510