Two Rudders?
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- Almost a Finish Carpenter
- Posts: 80
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- Boat Name: ESPADON Kittiwake
- Boat Type: Sabre 28, Alden Challenger
- Location: Central Virginia
Two Rudders?
Check out this Cal 36 on ebay, it appears to have two rudders....very odd.
Jimmy Small
http://cgi.ebay.com/ebaymotors/1968-Cal ... dZViewItem
Jimmy Small
http://cgi.ebay.com/ebaymotors/1968-Cal ... dZViewItem
- Tim
- Shipwright Extraordinaire
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- Boat Name: Glissando
- Boat Type: Pearson Triton
- Location: Whitefield, ME
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The one on the trailing edge of the keel is probably a trim tab, like the 12 meters used for years. I guess the theory is that by adjusting the trailing edge of the keel with that movable appendage, lift can be increased for higher pointing ability. Or something like that. These things never became commonly used. Is if because they only really work in specific designs or situations, or because of the additional complexity, I wonder.
Imagine sailing with these two tillers in your cockpit, though. That must be a bit awkward. Good for starting conversations with strangers, though.
Imagine sailing with these two tillers in your cockpit, though. That must be a bit awkward. Good for starting conversations with strangers, though.
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Forum Founder--No Longer Participating
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- Candidate for Boat-Obsession Medal
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I had a dock-neighbor once who planned to mount swim-fin-like appendages to the after end of his hull (one on each side). The plan was that as the boat pitched in an ocean swell, they would propel the boat like fins on a swimmer do. I'm not sure if he ever implemented the plan (I bet I could find out though).
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- Master of the Arcane
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- Boat Name: Hirilondë
- Boat Type: 1967 Pearson Renegade
- Location: Charlestown, RI
The designer couldn't decide between a full keel/keel mounted rudder and a fin keel/spade rudder, so he did both.
Dave Finnegan
builder of Spindrift 9N #521 'Wingë'
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Gresham’s Law of information: Bad information drives out good. No matter how long ago a correction for a particular error may have appeared in print or online, it never seems to catch up with the ever-widening distribution of the error.
builder of Spindrift 9N #521 'Wingë'
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Gresham’s Law of information: Bad information drives out good. No matter how long ago a correction for a particular error may have appeared in print or online, it never seems to catch up with the ever-widening distribution of the error.
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- Skilled Systems Installer
- Posts: 254
- Joined: Thu Jan 06, 2005 12:39 pm
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Believe it or not my Dad designed the first trim tab- that's on the rudder for Sparkman & Stevens on Intrepid. It was controlled w/ a small wheel inside the larger wheel. The idea was to gain lift to windward by creating I guess a foil on the trailing edge of the keel- The wheel allowed you to change it port or starboard as you tacked. I also think it could be locked in with the main rudder to give you more rudder power. My older brother still has the working model of the whole gizmo Dad made to show Olin & Rod Stevens (sp?).
He also came up w/ the coffee grinders hanging under the deck rather than topside to get weight & windage below decks. I remember sitting in a chair in our cellar pumping handles with my arms and then feet so he could determine the best way to grind. Bottom line was hands were much faster but not as strong. That was fixed by shifting gears- which he changed from the old style of buttons you hit w/ a fist to a foot pedal that allowed continuous grindng. I don't think he was too popular w/ the grinders who spent the race below decks rather than up in the breeze!
He also came up w/ the coffee grinders hanging under the deck rather than topside to get weight & windage below decks. I remember sitting in a chair in our cellar pumping handles with my arms and then feet so he could determine the best way to grind. Bottom line was hands were much faster but not as strong. That was fixed by shifting gears- which he changed from the old style of buttons you hit w/ a fist to a foot pedal that allowed continuous grindng. I don't think he was too popular w/ the grinders who spent the race below decks rather than up in the breeze!