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  #16  
Old 07-19-2010, 02:40 AM
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Perm Stress Perm Stress is offline
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3) battens in the leach: about 1metre long, parallel to luff. When reefing, genoa is rolled until batten is next to foil, then one extra turn - so that between batten and part of sail still flying therre is always 1 to 1,5 turn of material on the foil.
i couldn't visialize it in my mind. could you help me please. batten parallel to luff?

regards

Please see attached sketch for vertical battens.


"And also, please say your opinion about adding an inner forestay as i tried to show it on the picture and using staysails for strong wind conditions.
when it really blows like 35 knots+ , i can furl the genoa and go my way by reefed mainsail and small staysail. what would the pointing ability of this conbination?"

Inner forestay in your photo is too low in my opinion. Area of sail will be ~25% of fore triangle. This way staysail will be really storm size, but too small for ordinary Force 5 or 6. 60 to 65 % of mast height and parallel to headstay would be about right. Than staysail area will be ~36... 42% of fore triangle.

Please note, that in order to use staysail for upwind work, new sheet leads, closer inboard, will be necessary. Angle between CL and line trough staysail tack and sheet block has to be ~10...12 degrees, when viewed from above.

Special consideration will be necessary for interference between staysail clew/sheet and lower shrouds of the mast. Some careful on-site measurements will be necessary.

With decent sails and proper sail trim pointing ability would be about same as with full genoa in moderate conditions.

(sound like lots of additional expense and work.... )

"and yes the propeller make noise under sail. i fix it by pulling the throttle back and when it is on gear it doesn't move."

Generally, free spinning propeller propeller cause less drag than stopped one. This is from my direct experience, not from any theories about it.
It is only beneficial to stop folding propeller, as then blades fold and "dissapear" from waterflow. Same for feathering one. Stopping could be beneficial for two-bladed fixed prop, provided it is stopped in such a position, that is (almost) completely hidden behind thick keel of your boat.
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File Type: pdf vert batt.pdf (2.3 KB, 62 views)
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  #17  
Old 07-19-2010, 10:14 AM
celenoglu celenoglu is offline
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An inner forestay might be helpful. But instead of making it as a cutter it is much better tu make it a slutter type. a cutter type of inner orestay will need support from the same point on the mast backwards which means new back stays. a slutter will not need back stays or any type of extra support. I would never use a cutter type inner forestay if it is not supported by backstays if the wind is really blowing.
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  #18  
Old 07-19-2010, 01:38 PM
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Originally Posted by celenoglu View Post
An inner forestay might be helpful. But instead of making it as a cutter it is much better tu make it a slutter type. a cutter type of inner orestay will need support from the same point on the mast backwards which means new back stays. a slutter will not need back stays or any type of extra support. I would never use a cutter type inner forestay if it is not supported by backstays if the wind is really blowing.
Cutter stay could be supported well with simple additional shrouds with no need for running rigging, as in attached sketch. This kind of arrangement i have seen many times. Mechanical logic behind it is also straightforward and correct.

On the other side, runners could be set up so that main boom do not foul them. Then, because cutter stay will need really strong support when mainsail is deeply reefed or dropped, so mainsail head will not foul the runners too ->->-> in the end, with deeply reefed (dropped) mainsail, both runners could be set up taut and forgotten. In good weather (and full mainsail) runners are not necessary anyway, so could be lashed at the mast and forgotten.
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  #19  
Old 07-19-2010, 02:57 PM
Paul B Paul B is offline
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Originally Posted by Perm Stress View Post
Cutter stay could be supported well with simple additional shrouds with no need for running rigging, as in attached sketch. This kind of arrangement i have seen many times. Mechanical logic behind it is also straightforward and correct.
Six degrees? Really?
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  #20  
Old 07-19-2010, 03:27 PM
urisvan urisvan is offline
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you are right, cutter stay with runner will give a very good suppert to mast. even if a shroud and forestay broken, the mast will be supported by those(inner forestay and runners). this sound excellent from security point of view.
the other important point is what should be my sail set?
my priority is ability to winward.
and i have only an old %120-130 genova on a furling(and it is loosing its shape when i furl even a little)
even old, this %120-130 genova is ok in 15 knot wind even if i go clouse haulded. but in 20 knots and choppy water there is a trouble. this is the point that i began to worry about security.
So i even i dont like it i need some new sail or sails. i am trying to find the optimum combination. As i said my priority is ability to winward.
let me say what i have in my mind: add some luff padding and battens to leach to my existing genoa so i, can furl it %20-30 without ruining its shape. this will handle me until 25 knots wind also with a second reefed mail sail. after that i will furl the genova compilately and open my new build cutter staysail.
with my second reefed mail sail and cutter forestaysail i guess i can handle winds till 30 knots. after that i will third reef the main sail and change the hang on staysail to a stormsail (smaller staysail). And after 40 knots i will close the mainsail and go only with storm sail.
what do you think about this plan? will it function...
By that way, i will buy two staysails, add cutter stay and runners and rectify my existing genoa by adding luff padding and leach battens.
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  #21  
Old 07-20-2010, 04:03 AM
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Originally Posted by Paul B View Post
Six degrees? Really?
6 degrees in side view. It will not hold cutter stay bar-taut; it will hold under reasonable tension; please note, that they are additional shrouds, and act together with other staying.

By the way, in swept-spreader rigs, intended to go without runners, ~5degrees angle between mast and shroud in side view is universally accepted minimum.
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