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Topic-icon Weather helm...faults and cures

7 months 4 days ago #202 by multithom
multithom created the topic: Weather helm...faults and cures
Triak has weather helm built in--all well designed boats do. It is just a matter of designing the boat so the center of effort of the sailplan is offset slightly by the center of effort of the underwater foils. One of the reasons it is better to have weather helm than not is so if you are unable to steer the boat (fell off, unconscious...), the boat will go into irons and stop.

Triak as a lot of weather helm in bigger wind. A lot of this is due to the mainsail hooking...that moves the center of effort of the sailplan aft. You can fix this by not sheeting so hard, but then you won't be able to point very well. You can fix it some more by inserting a stiffer batten in the mainsail, but you probably will end up hooking the main anyway in a stiff breeze. Since the wind where I sail is pretty stiff all the time, I went ahead and removed the mainsail roach so the mainsail is a pintop. I no longer need battens and hooking is minimal--pintops also point higher than square tops. Most of you won't want to do this if you sail in a moderate wind area.

Another way of removing some weather helm is to move the center of effort of the underwater foils further forward. This can be achieved by changing the rudder so it hangs more vertically or tucked under the transom a tiny bit. You may have noticed that when fully down, the rudder is slanted slightly aft instead of vertical down. You can easily fix that in about an hour.

Remove the rudder pivot bolt. Hold the rudder vertically down or tucked slightly under the transom (leave the control lines attached since they are part of the interference that keeps the rudder from hanging vertical). Mark the spot on the rudder through the pivot hole. On mine, it was slightly above (rudder down looking from port side) and left of the existing pivot--it actually overlapped the existing pivot by about 1/8 inch.

Remove the lines. Mix up a batch of bondo or stick epoxy or something similar and fill up the existing pivot. Wait for it to cure (half hour for bondo). Drill a new 5/16" pivot hole where you marked (be as vertical as possible-use a drill press if you have one). Replace the rudder control lines and reinstall the rudder.

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