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Old 11-03-2016, 17:16   #1
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Twin v. Single Keels

Can anyone explain to me the pro's and con's of having twin keels over a single?
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Old 11-03-2016, 17:22   #2
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Re: Twin v. Single Keels

Bilge keels allow a boat to dry out and not fall over, but they introduce more drag when sailing.


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Old 11-03-2016, 17:42   #3
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Re: Twin v. Single Keels

Here you have some information:
Bray Yacht Design and Research Ltd. - The Advantages of Twin Keels

A modern twin keel can offer very good performance allowing a smaller draft. It is not as good regarding absolute sail performance as a deeper bulbed or torpedo keel but is the more efficient solution regarding performance if you need a smaller draft with the exception of a modern swing keel (with all the ballast on the keel).

But with a swing keel up you cannot sail, only motor, it is more expensive and has more maintenance.

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Old 11-03-2016, 17:46   #4
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Re: Twin v. Single Keels

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Originally Posted by Polux View Post
Here you have some information:
Bray Yacht Design and Research Ltd. - The Advantages of Twin Keels

A modern twin keel can offer very good performance allowing a smaller draft. It is not as good regarding absolute sail performance as a deeper bulbed or torpedo keel but is the more efficient solution regarding performance if you need a smaller draft with the exception of a modern swing keel (with all the ballast on the keel).

But with a swing keel up you cannot sail, only motor, it is more expensive and has more maintenance.

That boat is just frikin cool.
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Old 11-03-2016, 18:16   #5
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Re: Twin v. Single Keels

Hope "blue boat" has mast, boom and sails.
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Old 11-03-2016, 22:30   #6
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Re: Twin v. Single Keels

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That boat is just frikin cool.
Yeah, and look at how stable it is, held down with four ocky straps.

From a wetted surface viewpoint those skinny foils look as though they would not add much wetted surface anyway. Looks fast just sitting on the trailer.
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Old 11-03-2016, 22:49   #7
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Re: Twin v. Single Keels

Sure doesn't look like a typical tiller steered 27 footer made from plywood does it? It is, RM 890.
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Old 12-03-2016, 08:42   #8
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Re: Twin v. Single Keels

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I had a bit of a headache last night so I did not read that article until this morning, really really great article, thank you really explained things to me and validated a lot of thoughts that I had.

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Old 12-03-2016, 09:05   #9
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Re: Twin v. Single Keels

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Hope "blue boat" has mast, boom and sails.
Yes, all that and it is also a very good sailboat that sails very well even with light winds, a sailor's boat. That boat become quickly famous because one of the first clients was probably the world's best ocean monohull Solo racing sailor, that bought one for cruising.


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Old 12-03-2016, 13:55   #10
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Re: Twin v. Single Keels

I think all boats are designed for a purpose and a locale. If I were cruising in northern latitudes where there were shallows and big tidal flows, I'd probably look for a boat with bilge keels so I could do this without spilling my coffee or Sheep Dip:
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Old 12-03-2016, 17:25   #11
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Re: Twin v. Single Keels

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I think all boats are designed for a purpose and a locale. If I were cruising in northern latitudes where there were shallows and big tidal flows, I'd probably look for a boat with bilge keels so I could do this without spilling my coffee or Sheep Dip:

Sheep dip????


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Old 12-03-2016, 17:36   #12
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Re: Twin v. Single Keels

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Sheep dip????


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Yep, pretty good stuff.... good enough to warrant bilge keels. Maybe that's why they have so many bilge keelers in UK?
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Old 12-03-2016, 17:51   #13
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pirate Re: Twin v. Single Keels

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Sheep dip????


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Obviously took DOJ and his Goat seriously.
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Old 12-03-2016, 18:09   #14
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Re: Twin v. Single Keels

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Obviously took DOJ and his Goat seriously.

That was the youngest goat to solo circumnavigate!!


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Old 12-03-2016, 21:32   #15
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Re: Twin v. Single Keels

So, twitn keel or Catamaran that is the question?
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