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PostPosted: Thu May 24, 2012 5:01 pm 
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Location: Florida
The post about retrofitting a 16 got me rethinking this. I get that the purpose is to provide a smooth air flow along the front of the sail. I usually(always) set it on the beach and forget it.

The above post indicates that some Nacras use(d) camcleats for this adjustment. That leads me to think that some people adjust this on the water. That Hobie put that V (that I hate, is hard to adjust, and creates dangerous situations when it fails) cleat that regularly pulls loose instead of a real cleat also leads me to believe that Hobie thought this was an active adjustment.

Does ANYbody adjust this on the water?

If i worked out a way to adjust this from either side on the fly would there be be any advantage? And would it be class legal?

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PostPosted: Thu May 24, 2012 7:14 pm 
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Location: BC, Canada
This is how to use mast rotation on H17:
http://www.hcana.hobieclass.com/site/hobie/hcana/downloads/class%20info/Hobie17/Sweet%2017%20Part%201.pdf

JSWoerner wrote:
hard to adjust, and creates dangerous situations when it fails) cleat that regularly pulls loose instead


If you cleat get loose, it may be worn out and need replacement, or your line may be of wrong size. To avoid getting completely out, you put figure-8 knot at its maximum extend.

I do adjust mast rotation on the water, but not often.

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PostPosted: Thu May 24, 2012 8:30 pm 
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Location: North Carolina
Most folks set it and forget it. There is some advantage in adjusting in light air but not enough to worry with it. It controls the original dacron sail shape the best by changing the fullness.


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PostPosted: Fri May 25, 2012 1:30 pm 
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Location: Jersey Shore
If you're course racing, then the general rule is to point the rotation arm at the shroud for upwind sailing and release the rotator to at least 90 degrees for downwind sailing.

For fun sailing, I generally just sheet in, point the arm a the shroud, and leave it. It really makes very little noticable difference. Mainsheet, traveler, downhaul, and steering are the primary controls.

sm


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PostPosted: Fri May 25, 2012 3:07 pm 
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Location: SE PA/ Chesapeak Bay
Hi,

Yes it is a more "minor" adjustment then let's say sheet tension ... but when you are messing w/ the likes of Mr Jim Sohn ... or Mr Stephen Cooley ... proper mast rotation makes a difference ....

The shrouds are a good starting place for most Hobie factory sails ... but it does depend on the sails ....ex: my "Blue Hawaii's" circa 1984/85 seemed to run best w/ the rotator pointed at or slightly ahead/forward of the shrouds .... my "All White" circa 2007 seem to run better w/ the rotator pointed slightly aft of the shrouds. The more "blown" out the mainsail the more rotation that is needed ... this is because as the mast is rotated, the mast's trailing edge moves forward ==> pulling the luff forward and thereby pulling the sail tighter/flatter (assuming all other adjustments remain the same ...) Don't forget that the battons and how they'rs shaped/tuned/tensioned has a influence on where the max depth of the sail is located also and could effect the mast rotation settings. As does the downhaul. It's all about the sail depth/pocket ... where is it and how deep is it ...

At the 2007 H18 NAC's I watched Mr Jim Sohn make small adjustments to his rotation ... and he would just slowly walk away on us .... of course I'm not anywhere near the sailor Jim is !!!! So there was more then one reason why he kicked my butt ...

I replaced my Mast Rotation Jr Jamcleat w/ a "spinloc" ... so my 12yr old niece (at the time) could adjust the mast rotation ... and outhaul also .... SWEEEEETTT ......

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H-18 mag/ #9458
Fleet 54 Div 11


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PostPosted: Fri May 25, 2012 4:26 pm 
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Location: Florida
O.K. I read the the 17 article and I have a couple of questions.

First, my boat is an '84 and the mast is stock, no comptip. Am I really going to get any mast bend?

Second, if I try, aren't I REALLY putting a LOT of stress on the forestay and bridle

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PostPosted: Fri May 25, 2012 7:08 pm 
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Location: SE PA/ Chesapeak Bay
... 17 article????

I'm confused ...

As for a all-aluminum mast .... the downhaul will induce mast bend ... if you tension the diamond wires it can induce prebend also (but H18's don't general run w/ that high of Diamond Wire tension w/ factory sails ... after market ????)

The more you rotate the mast the easier it is to induce mast bend ... it has to do w/ the major or/and minor axis of the teardrop shape of the mast ...

The loading on the bridles/forestay has more to do w/ mainsheet tension then the mast rotation/downhaul/outhaul ... (that why you need the jib sheeted tight ... and then you sheet the last couple of inches of "main" sheet) ... the mast act as a folcrum ... pull down on the back ==> the mast head moves back ==> forestay/bridles are pulled tighter ==> the leading edge of the jib has a straighter entry into the wind.

Ok ????

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H-18 mag/ #9458
Fleet 54 Div 11


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PostPosted: Sat May 26, 2012 8:28 pm 
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Joined: Tue Aug 23, 2011 1:36 pm
Posts: 34
Do you still have the black plastic cleat? My out haul cleat (same part) was worn out. When I went to my Hobie dealer he had me replace it with an aluminum one. It works much better. I haven't replaced the one on my rotation adjustment yet but it is on the list of things to do.

-Rowdy


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