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Old 04 September 2009, 05:13   #11
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Country: UK - England
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My understanding is (I'll use port & Stb to avoid left/right confusion) - if you have to apply port steering, then you want to get the trim tab to do this for you . As the trim is at the back of the outboard you need to force the back of the engine to port - so to do this you turn the trim tab over to the stb side of the boat .

The trim tab will try & run straight through the water rather than at an angle that is created with the motor straigt ahead (for the same reason that your prop pushes you forward, wings get lift etc etc) - so will try & push the back of the leg to port to acheive this. And vice-versa ...........

Hey presto the tab is now providing the force so you dont have to on the helm !

(I think.................)
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Old 04 September 2009, 11:15   #12
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The trim tab (well, mine does, anyway) also has a bit of an airfoil shape, though, so will try and pull a bit to the arched side. So it doesn't try to run in a true straight line, but a slight offset.

jky
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Old 06 September 2009, 11:14   #13
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Quote:
Originally Posted by Blackroady View Post
My understanding is (I'll use port & Stb to avoid left/right confusion) - if you have to apply port steering, then you want to get the trim tab to do this for you . As the trim is at the back of the outboard you need to force the back of the engine to port - so to do this you turn the trim tab over to the stb side of the boat .

The trim tab will try & run straight through the water rather than at an angle that is created with the motor straigt ahead (for the same reason that your prop pushes you forward, wings get lift etc etc) - so will try & push the back of the leg to port to acheive this. And vice-versa ...........

Hey presto the tab is now providing the force so you dont have to on the helm !

(I think.................)
Ah! Yes. (I think). Many thanks.
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Old 27 September 2009, 15:51   #14
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The main object of the trim fin is not to turn the boat at all.

The whole idea is to help the steering effort required.
If you can steer easy to the right but its hard to steer to the left then you adjust the
tab to help against the torque effect.

Unless an engine is offset on the transom it will walk to one side no matter how much
trim you give it.

In an ideal world the outboard should be able to steer to left and right with the same
amount of effort required.


phill
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