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  #1  
Old 05-02-2010, 03:52 PM
captjj captjj is offline
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Mast rake

What is the effect of mast rake on a 43 ft ketch. I would like to reduce weather helm.
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Old 05-02-2010, 04:25 PM
Stumble Stumble is offline
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I need a lot more information, type of boat, sail plan, age of sails, ect to begin to answer this question reasonably. Mast rake is probably not the first place I would start to solve this problem though.
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Old 05-02-2010, 07:24 PM
Paul A Paul A is offline
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Mast rake is commonly used to solve this problem, though this depends on other questions being answered first. Some of these would be what changes have been done to the rig, the headsails normally used, any changes to keel or rudder, how much helm defection on a closed hauled course in moderate wind. Quickly put, removing rake from the main mast can help reduce weather helm.
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Old 05-02-2010, 08:53 PM
ancient kayaker ancient kayaker is offline
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What sail choices do you have? On a ketch, easing or reefing the mizzen or a bigger jib would do the same thing surely?
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Old 05-03-2010, 12:44 PM
Stumble Stumble is offline
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Paul,

I wasn't saying that mast rake won't help the problem, but in my experience there are often a lot of other issues that should be addressed before changing the rig tune to solve a helm problem.

The most common issue is simply poor mainsail trim, normally caused by carrying the traveler too high. Simple soluton here of course is to drop the traveler and sail off. Now if there isn't a movable traveler on the boat it gets more complicated, but the simple answer is to put the vang on heavy to control the leach, and use the sheet as a traveler. The second solution of course is really questionable, and I don't understand why some people don't like travelers.

Poorly trimmed jibs (almost always not far enough in, or leads in the wrong place) are probably the second most likely cause of excess weather helm. Particularly on cruising boats where the jib telltails have fallen off and the sail is trimmed to the 'bubble'. Here just adding proper telltales, and getting the sail set properly can often cure weather helm issues.

Third in my experience is jibs that are too small for the boat. A lot of cruisers like to step down to a very small headsail to make sail manipulation easier, without realizing that they are unbalancing the boat at the same time.

In short while mast rake is a possible sollution, it is not the first thing I would try to correct. Particularly since in my experience poor sail trim is almost always the culprit.
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Old 05-03-2010, 04:32 PM
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gonzo gonzo is offline
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Can you explain more in detail when the weather helm is a problem? You may be overcanvassing.
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