Author Topic: One thing puzzels me  (Read 1267 times)

Offline BellaCat

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One thing puzzels me
« on: May 07, 2015, 02:39:56 AM »
I am new to sailing and own a Sun Cat 17 . One thing puzzels me, in light air (but have also noticed in wind 10-15) while tacking both to port and starboard as the boom crosses and I straighten the rudder the boat continues to turn away, even if I push the helm all the way over it continues to turn away. Only way I found to stop it and turn back up is to let the sheet almost all the way out. That stops the turn then as I pull in on the sheet and the sail picks up the air, I have proper helm. My guess is that it has something to do with the depth of the keel. I have tried different elevations of the keel and have noticed some improvement but still have not solved the problem. Typically sailing in a river so there is some current, upwind and down river.
Will be interested in reading your opinions.

Offline rbh1515

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Re: One thing puzzels me
« Reply #1 on: May 07, 2015, 04:10:11 PM »
When you are sailing close to the wind, how far in do you have the sail trimmed.  On sloops the main is sheeted in close to the midline, but on a cat the sail is trimmed more like a jib/Jenny...so it is further out.  Maybe this is the problem?
Rob
2015 Horizon Day Cat, Waters End

Offline Craig

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Re: One thing puzzels me
« Reply #2 on: May 07, 2015, 05:28:08 PM »
A couple of possibilities. First the centerboard. As a novice sailor, keep it all the way down except when running dead downwind. Even downwind you really don't need to raise the board(centerboard adjustment is in chapter two!). Rudder...Do not over control(over turn)the rudder on tacking. You need to maintain speed while tacking. If you slow down too much the boat/rudder will "stall" and the rudder will lose effectiveness. Overturning the rudder causes it to act like a big brake. Hence the boat will fall off the wind as you have described as the bow gets blown off to leeward. Use the minimum rudder to come through the eye of the wind and maintain maximum speed. Your comment about pushing the helm all the way over is my clue as to what is going on. Your boat speed is to too slow and the rudder does not have enough lift to counter the pressure of the wind on the bow. Current can be an issue and push the bow around. again be judicious with the rudder and ease off a little sooner knowing that the current will push the bow around. Boat speed equals lift/control. Slow speed equals wallowing/poor control. Hope this makes sense and helps. We have all been there as novice sailors!
« Last Edit: May 07, 2015, 05:33:27 PM by Craig »
Craig, Horizon Cat "Kailani"  Punta Gorda, FL

Offline BellaCat

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Re: One thing puzzels me
« Reply #3 on: May 07, 2015, 11:45:54 PM »
Thank you both for your quick reply. I do think I strong arm the rudder and the phrase,  "boat/rudder will "stall" and the rudder will lose effectiveness" seems to describe exactly what I think is happening. Can't wait to get back on the water and work on my technique.

Offline hoddinr

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Re: One thing puzzels me
« Reply #4 on: May 08, 2015, 07:42:16 AM »
BellaCat,

Keep the boat driving through the tack if you can.  Imagine a big buoy that your going to turn around. Make the boat describe a circle around it as you tack, keeping momentum (if speed allows) as you go.  That way you won't stall the boat, and you will already be moving when you have changed tacks. 

Avoid spinning the boat in its own length and then having to start sailing again. 

Ron

Offline Craig

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Re: One thing puzzels me
« Reply #5 on: May 08, 2015, 08:47:30 AM »
One further thought. If you have the stock flat plate rudder it will "stall" at a lower angle of attack than a foiled rudder. The foiled rudder is much more efficient especially at low speeds and is a worthwhile addition to the Suncat if you don't have one. Sail On!
Craig, Horizon Cat "Kailani"  Punta Gorda, FL

Offline BellaCat

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Re: One thing puzzels me
« Reply #6 on: May 08, 2015, 12:51:27 PM »
I bought the boat with a recently installed Unifoil Kick-up Rudder 

Offline JBC

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Re: One thing puzzels me
« Reply #7 on: May 08, 2015, 11:29:51 PM »
Interesting discussion on tacking a cat-rigged ComPac.  The  CP16 also reguires some technique to avoid the same over-momentum tendency when tacking.  I've not sailed a ComPac cat, only smaller cat rigged dinghies (which in light air sometimes have the opposite problem: no momentum).  I like Craig's description of the problem and solutions, and will try his suggestions on my sloop-rigged 16/3.  I'm not a novice, but there is still plenty to learn!

Jett
« Last Edit: May 08, 2015, 11:39:48 PM by JBC »

Offline capt_nemo

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Re: One thing puzzels me
« Reply #8 on: May 08, 2015, 11:58:37 PM »
Different sailboats handle differently when it comes to tacking under different wind conditions and especially in light air.

Ditto on the good comments from those above about foiled rudders, maintaining momentum, and an easy (non aggressive) hand on the tiller to steer a nice smooth curve through the tack.

Maintaining momentum is also quite important in medium to heavy air, especially in a steep chop. Without sufficient momentum it is easy to get hung up "in irons" and have to regain movement and control by falling off or backing the jib.

It will become second nature with practice, practice, and more practice.

I've found that the addition of a foresail to my Cat Rigged Sun Cat assists tacking under all conditions by providing the additional DRIVE that only a foresail can, especially in heavy air with a steep chop and REEFED main.

capt_nemo