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  #1  
Old 10-15-2008, 06:32 PM
el moro el moro is offline
 
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Location: spain
conversion from gaff cutter rig to bermudan cutter

i have a 26ft double ender colin archer type designed by john leather. I am thinking of converting her to a bermudan 3 headsail rig ( one forestay removable and only for a stormsail)
anybody out there who can point me in the right direction for some advice about rigging, sailplans, balance etc etc
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  #2  
Old 10-15-2008, 10:19 PM
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PAR PAR is offline
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You will need to have a designer work up a new sail plan for you, so the boat can balance properly. There are several here that can do the work or you may find one locally.
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  #3  
Old 10-16-2008, 12:07 AM
diwebb diwebb is offline
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Hi El Moro,
when changinga sailing rig radically as you are suggesting consideration should be given to many factors. When a boat is designed for a gaff rig the hull is usually a traditional long keel type of relatively high displacement, a gaff rig with its low center of effort and large area is suited to this type of hull. The stresses produced and transferred to a hull by a gaff rig are less than produced by a bermudan rig. Performance under a bermudan rig may in fact be less than under the gaff rig, as the actual sail area may be less and the hull may not suit the higher pointing characteristics of the bermudan rig. The gaff rig is easier and cheaper to maintain than a bermudan rig. So before spending a lot of money converting please think through all of the connotations of what you are suggesting. I have owned both gaff and bermudan rigged boats so am aware of the good and bad points of both rigs. I agree that you should consult a reputable boat designer if you decide to proceed with the change, but you must remember that he may just look at it as a design comission and may notl ook at the question of why do it in the first place.
All the best with the project.
David.
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  #4  
Old 10-24-2008, 06:02 PM
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Tcubed Tcubed is offline
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I could not agree more with Diwebb.

In a word-Don't do it!

No seriously, why are you considering this conversion and what advantages do you hope to gain from it?

I have seen so many really nice gaffers ruined by exactly this kind of conversion. And i'm not being sentimental. I have many sea miles in both kinds of rigs and i've studied aerodynamics, so i say this for completely practical reasons. It is very doubtful that you will get better performance, in fact it is quite likely the performance will be worse. And if, as it almost certainly will, it means the aerodynamic center of the sails moves higher up you will notice the boat becomes harder to control at the helm, even if it is perfectly balanced.

Then there are the higher hull loads to consider. A lot of wooden boats were not designed and built with a high compression mast in mind. I know of too many wooden boats which did not leak very much at all become sieves under sail with their new tall rigs. In extreme cases (and i've seen this many, many times too) the shrouds' tension deform the boat over time. Pay close attention to wooden yachts and you will eventually notice one with the cabin sides flaring outwards. You can be certain it was not made that way. What happened is excessive shroud tension has compressed the boat so the decks are now partly shoved under the coach roof...
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  #5  
Old 10-26-2009, 05:54 PM
kattegat26 kattegat26 is offline
 
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Archer/leather 26'

El Moro
Bit of a stab in the dark after the thread has been asleep for a year but is your boat the Kattegat 26 built by Jim Spencer at Brightlinsea?
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  #6  
Old 10-29-2009, 12:07 PM
dskira dskira is offline
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Quote:
Originally Posted by diwebb View Post
Hi El Moro,
when changinga sailing rig radically as you are suggesting consideration should be given to many factors. When a boat is designed for a gaff rig the hull is usually a traditional long keel type of relatively high displacement, a gaff rig with its low center of effort and large area is suited to this type of hull. The stresses produced and transferred to a hull by a gaff rig are less than produced by a bermudan rig. Performance under a bermudan rig may in fact be less than under the gaff rig, as the actual sail area may be less and the hull may not suit the higher pointing characteristics of the bermudan rig. The gaff rig is easier and cheaper to maintain than a bermudan rig. So before spending a lot of money converting please think through all of the connotations of what you are suggesting. I have owned both gaff and bermudan rigged boats so am aware of the good and bad points of both rigs. I agree that you should consult a reputable boat designer if you decide to proceed with the change, but you must remember that he may just look at it as a design comission and may notl ook at the question of why do it in the first place.
All the best with the project.
David.
Very well said by an experienced sailor. Follow his advice.
Cheers
Daniel
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  #7  
Old 10-29-2009, 03:10 PM
peter radclyffe's Avatar
peter radclyffe peter radclyffe is offline
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i cant see the red cross, is it the Odd Times
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  #8  
Old 02-19-2010, 11:13 AM
The copper guy The copper guy is offline
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Sorry m8 don't do it,Rigs fol ow fashions and not common sense
You are about to buy bell bottom pants
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