| Re: Up Wind rudder stall
[Re: jes9613]
#33977 06/02/04 04:11 PM 06/02/04 04:11 PM |
Joined: Oct 2001 Posts: 95 Flensburg, Germany Fritz
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Posts: 95 Flensburg, Germany | John, most of the time it is the rudder itself. Rudders on a Hobie 16 must be extremely stiff to prevent a spin out. That can only be solved by using slim profile and stiff rudders. Carbon Fibre is the best solution nowadays. If you have Lexan rudders, okay, you will always have that problem. If you have the old black EPO rudders, the problem will be less but still existing. The factories do not such a good job on rudders, even with the white rudders you have a too thick profile that let the rudders stall, if you sheet in too tight and move the rudders extreme. Solutions are there on the market.
Another practical one: Do not move the rudders so quickly, but try and steer softly that may also help. Raking the mast needs to be "counter" raked with the rudders, you have to rake them forward, so that the weather helm is gone. But rake only is not the problem for stalling.
Hope this helps a bit. Happy to tell you more.
Fritz | | | Re: Up Wind rudder stall
[Re: jes9613]
#33979 06/03/04 07:06 PM 06/03/04 07:06 PM |
Joined: Aug 2001 Posts: 251 beaufort, sc dannyb9
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Posts: 251 beaufort, sc | what about your jib halyard tension? if you can't point, maybe your jib luff is sagging. extra jib halyard tension is needed to keep the jib luff wire loaded upwind when the wind builds. what looks good on the beach may not be enough out in a 15- 18kn breeze sailing hard on the wind. if the forestay becomes taught going upwind the jib luff will sag and you wont be able to point.
marsh hawk
| | | Re: Up Wind rudder stall
[Re: sail7seas]
#33982 06/04/04 11:38 AM 06/04/04 11:38 AM |
Joined: Aug 2001 Posts: 251 beaufort, sc dannyb9
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Posts: 251 beaufort, sc | yes you need a LOT more tension on your jib halyard. the forestay should have NO tension while you are sailing hard to windward. or on any other point of sail. ALL the load should be on the jib luff wire. the purpose of the forestay is to hold the mast up when the jib is not being used. you need the extra forestay adjuster to let the mast lean back enough to achieve block to block sheeting. and a little slack in the sidestays is good because the mast wont rotate freely if they are too tight. but the forestay should carry no load while sailing. when i set up on the beach i have about 8-12" of slack in the forestay, that means if i pull the slack out of the forestay toward the mast, as high as i can reach,there is about a foot of distance between the slack forestay and the jib luff wire. depending on how hard its blowing. when you are block to block sailing hard into 18 kn, your forestay still needs to have a little slack in it so that the jib luff wire is carrying ALL the load of the mast and mainsheet sheeted to the max- so that the jib luff wire is as straight as possible upwind. a curved jib luff creates a fuller sail which is slow upwind. especially when its blowing. when winds are lighter you dont need as much halyard tension because you shouldn't be sheeting as hard. the goal is to be ALMOST block to block with ALL the load on the jib luff wire and NO tension on the forestay. the forestay should be bowed, the jib wire should be as straight as possible : )
Last edited by dannyb9; 06/04/04 12:11 PM.
marsh hawk
| | | Re: coke or pepsi
[Re: sail7seas]
#33984 06/04/04 01:24 PM 06/04/04 01:24 PM |
Joined: Aug 2001 Posts: 251 beaufort, sc dannyb9
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Posts: 251 beaufort, sc | uh, did i suggest releasing jib halyard tension? NOT. i recomend maximum jib halyard tension for all the above reasons
marsh hawk
| | | Re: Up Wind rudder stall
[Re: mmadge]
#33994 06/05/04 09:43 AM 06/05/04 09:43 AM |
Joined: Aug 2001 Posts: 251 beaufort, sc dannyb9
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Posts: 251 beaufort, sc | i am guessing that the mast forward setup was a result of the very windy conditions at the worlds and a desire to induce a lot of mast bend to flatten the main. the wind was around 20 kn for most of the regatta. sail7 said he was sheeting block to block with extreme mainsheet tension so i guess the modern short block system would still be needed. i am definitely going to try the mast bend thang, my crew and i are pretty light and the sea breeze has been kickin!
Last edited by dannyb9; 06/05/04 09:49 AM.
marsh hawk
| | | Heavy air/rudder stall
[Re: sail7seas]
#33995 06/07/04 07:29 AM 06/07/04 07:29 AM |
Joined: Jul 2001 Posts: 206 Virginia USA CMerrell
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Posts: 206 Virginia USA | Heavy air: Since opinions on rig set up seem to diverge as wind speeds increase, it is helpful to know the wind and sea state, and also crew weight, for heavy air rig set up. At the Worlds it looked like they had strong, steady winds and big (6 foot) waves. Also, the top teams were probably around the minimum crew weight. In that case, the Galvin set up makes a lot of sense. In the same conditions with heavier crews, backing off the jib halyard tension a smidge (.5 to 1 inch) would help to power up the sail plan to get through the waves. An "old school" technique is to back off jib halyard tension a lot (2 to 3 inches) in strong but very puffy wind. The idea is to spill power from the top of the main sail in the puffs. At some point the sail plan is taking all the wind power it can stand. Above that the sails need to be depowered and there are many techniques that will work and you can have very different set ups boat to boat. Wind, water and weight (3 W's) all need to be considered. Someone should write a book about that!  Rudder stall: Moving crew weight back on the boat can solve the stall problem. I don't know the theory why (rudder "digs in" more?). | | |
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