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Old 06-12-2012, 03:13 PM
Earl Boebert Earl Boebert is offline
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Partly Clubbed Jib (Sonder Class)

I've been studying Sonder boats and building a "Sonder-inspired" 36" model. The bulk of these boats used a short jib club/boom that ran from the clew of the jib along about 80% of the foot, with the rest of the foot loose to the tack. I've attached the sail plan I'm working from where the club is clearly visible. The picture of the German boat "Angela" shows it clearly, along with the effect on the shape of the jib. Even Nathanael Herreshoff did this on his Sonder "Bibelot."

I can't for the life of me understand what the reasoning was behind this feature. Anybody have a clue?

Cheers,

Earl
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Partly Clubbed Jib (Sonder Class)-sailplan.jpg  Partly Clubbed Jib (Sonder Class)-angela.jpg  
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Old 06-12-2012, 03:56 PM
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philSweet philSweet is offline
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It reduces the hook on the bottom of the jib. I've fitted them to several boats as an easy single hander mod. Small overlap sails can be made self tending with biggish clubs like that. Changes the location of the jib block which may free up space in the cockpit as well. In boats that don't have a jib track, a club allows you to fiddle with the lead angle to get the best all around performance. I like them a lot for low control effort sailing. Gust response can be adjusted by changing the sheet attachment at the club.
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Old 06-12-2012, 04:08 PM
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philSweet philSweet is offline
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Looking at the linesplan, I think the point is to run the jib on a jib traveller. This allows self tacking without any sheet adjustment. It works like a champ.

also, you can store the clubbed jib on deck ready to go in a way that you just can't do with a loose footed jib. I usually had a few hanks near the bottom and flew the top half loose. I could drop the sail, pull the head in towards the mast and stopper the sail to the club and walk away in ten seconds. Handy for cutter and slutter rigs.
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Old 06-13-2012, 05:38 PM
Earl Boebert Earl Boebert is offline
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Thanks for the explanation. But why not a boom along the whole foot of the jib, attached just at clew and tack like a model yacht?

Cheers,

Earl
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Old 06-13-2012, 08:59 PM
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gonzo gonzo is offline
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These boats were designed with cotton sails. They were cut flat and then stretched into a proper shape. However, they were not as rigid as modern cloth. The partial boom lets the leading edge curve more and the aft section flatten.
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Old 07-02-2012, 09:29 AM
Earl Boebert Earl Boebert is offline
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Here's the 36" LOA Sonder model that prompted the question on her first sail. Photos by Jay Eschenberg.

Cheers,

Earl
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Partly Clubbed Jib (Sonder Class)-blackchin1.jpg  Partly Clubbed Jib (Sonder Class)-blackchin2.jpg  
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Old 07-08-2012, 06:50 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
"But why not a boom along the whole foot of the jib, attached just at clew and tack like a model yacht?"

By locating the tack of the sail back from the stay ,(usually to a pedestal) the jib will flattened as it is hauled in.

But the jib will gain fullness as the sheet is released, the further off you sail the fuller it gets.

Self tacking with nice sail shape is the goal.

Downside is the limited sail area ,no overlap and the chance of ankle bashing if working on the foredeck.

FF
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