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 Post subject: Weather helm
PostPosted: Wed Jul 31, 2013 8:49 am 
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Joined: Wed Jun 20, 2012 11:08 am
Posts: 11
Location: Swakopmund Namibia
Hi All

I've been struggling with setting my rudders,to reduce weather helm. Some say toe-in others say toe-out. Some just shake their heads and sort of murmur ..I don't know.
Can anyone please give me a helpful hint, which doesn't involve a link to some elongated explanation.
Secondly : What's the issue with mast rake. How does it work?

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 Post subject: Re: Weather helm
PostPosted: Wed Jul 31, 2013 9:24 am 
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Joined: Mon May 09, 2005 10:25 am
Posts: 2552
Location: Jersey Shore
Toe in vs. toe out does not affect weather helm. Toe in & toe out affect drag. You never want the rudders toed out. They should be toed in about 1/8" (that is the measurement between the leading edges of the rudders is 1/8" less than the measurement between the trailing edges). Note that if your rudders are heavily toed out, then you will create a ton of drag and it may "feel" like weather helm. Also make sure your rudders are on the correct hull (the tiller arms should point inward).

Rudder helm is controlled by rudder rake and mast rake. The first thing is to make sure your rudders are locking down completely and properly. The upper tiller arm should be held down firmly when the rudders are properly locked down. If your rudders are not locked down all the way, then you will have a ton of weather helm. Next, make sure your mast rake is where you want it. For a H14, its going to be back pretty far (there are plenty of articles out there to help you fine tune your mast rake setting). In general, increasing mast rake will improve upwind performance, reduce the tendency to pitchpole, and will increase weather helm. Once your mast rake is set, sail the boat. If you still have excessive rudder helm, then you need to rake the rudders forward- that is, the bottom tip of the rudder needs to move forward. If you have rake adjustable castings, that is simply a matter of loosening the adjusting bolt, raking the rudder forward, and re-tightening the bolt. If you have fixed castings, then you need to fill and re-drill the pivot hole in the rudder blade to rake the rudder further forward. It is a trial and error process to get it just right.

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 Post subject: Re: Weather helm
PostPosted: Wed Jul 31, 2013 11:16 am 
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Joined: Mon Sep 19, 2005 10:18 am
Posts: 751
Location: Virginia Beach VA
I agree that severe weather helm is usually found on older boats where the cams are frozen or otherwise no longer function. Get your rudders to lock and then experiment with raking your mast until you get helm you can manage.

I have two boats with adjustable rudder arms. That just seems to allow one to remove slop from the locking mechanism. Removing the slop keeps the rudder from trailing aft which helps with weather helm. I doubt you can get any appreciable forward rake without filling and drilling the rudders though.


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 Post subject: Re: Weather helm
PostPosted: Wed Jul 31, 2013 10:06 pm 
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Joined: Wed May 05, 2010 8:28 am
Posts: 676
Location: Clinton Lake, KS
Raking the rudders under the boat reduces the amount of weather helm you feel by putting more of the rudder underneath the pin... giving you more mechanical advantage over the weather helm... It doesn't technically reduce it.... :wink: as all the forces are still in play... Ya just can control them with less force...


Mast rake is the angle of the mast... Moving it forward reduces weather helm... Raking the mast aft increases weather helm... This happens because the center of effort or center of pressure is moved aft when the mast is raked back... The further back the center of effort is... The more the boat is going to naturally want to round up to "weather".. Like a wind vane..

On something like a H14 this is also useful because it moves the center of effort over the rudders... and with the lack of dagger or center boards you can decrease the amount of leeway (the tendency of the boat to slip sideways) by loading up the rudders... This causes weather helm... Which is also causes drag... But it has been proven the tradeoff is well worth it on a H14 or H16...



Watch a windsurfer steer the board... The tip the mast forward to fall of the wind and turn down... Or tilt the rig aft to head up...


Try it on your H14... With just your body weight and sail trim you can almost steer the boat with the rudders in the up position.... :D


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 Post subject: Re: Weather helm
PostPosted: Thu Aug 01, 2013 8:54 am 
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Joined: Tue May 27, 2003 12:44 pm
Posts: 8966
Location: Oceanside, California
Fyi... some older rudder had asymmetrical foils due to sunken plastic on one side. Caused weather helm on one tack and lee helm on the opposite.

Rudder Rake and other FAQs are in the Sailing FAQ (top of the sailing forum).

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