Rudder help Please, 4ft vs 5 on 16ft boat???

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grey owl
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Rudder help Please, 4ft vs 5 on 16ft boat???

Post by grey owl » Thu Apr 26, 2018 5:00 pm

I've searched for information and the results seem to be all over the place. I'm getting ready to change my rudder configuration this summer. As much as its not like anything you might see in Florida my existing rudder does work well. My two issues are the amount of weight at the back of my boat and the amount I have to fight my stick in the wind.
in my perfect world i want to go to 4 ft airfoils mounted about 5 " from the prop but am worried i wont be happy with the control comming from a large single.

can anyone give me advice that will point me in the right direction?
Thanks will
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grey owl
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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by grey owl » Thu Apr 26, 2018 6:55 pm

,
so I guess 4ft will do and 5 will work better, thanks for the info

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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by SuprchgedPalmBeach » Fri Apr 27, 2018 4:25 pm

Typically goes along with blade diameter, a 4' rudder captures less air than a 5' rudder.
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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by Seadrift » Sat Apr 28, 2018 9:45 pm

4 or 5 either one will work, but it sounds like your fighting the rudder stick to turn. That being the case it sounds like you have a issue with the pivot point on your rudders not being balanced
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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by Web Foot » Wed May 02, 2018 2:02 pm

I had a pair of 4 foot on my boat. I switched them out for a pair of 5 foot. Night and day difference. It turns without hesitation now. Before it was slow to react when putting around, especially in deep water.

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grey owl
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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by grey owl » Wed May 02, 2018 3:47 pm

Thanks for the info, I guess I was hoping 4 would do it but it looks like 5 is the way to go. Anyone know the weight of a 5 ft airfoil rudder and where to get?
thanks

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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by Prototype » Wed May 02, 2018 11:56 pm

grey owl wrote:I've searched for information and the results seem to be all over the place. I'm getting ready to change my rudder configuration this summer. As much as its not like anything you might see in Florida my existing rudder does work well. My two issues are the amount of weight at the back of my boat and the amount I have to fight my stick in the wind.
in my perfect world i want to go to 4 ft airfoils mounted about 5 " from the prop but am worried i wont be happy with the control comming from a large single.

can anyone give me advice that will point me in the right direction?
Thanks will
If your fighting your stick its a geometry thing? Proper rudder setup can solve that. Never known that to happen on a cable steer boat but your post did not say if your cable or bell crank?
Before cutting and welding all new you could try 3 rudders? My experience with 3 rudders was like a jet boat that turned on a dime at 60 forgetting it was a airboat top heavy sob.
Either way, fighting the stick is not normal to a proper rudder setup!
A 5 foot rudder weighs 25% more than a 4 foot rudder of the same design and highly doubt rudder weight is your issue!
Something is off and your stick is telling you that!
Level it all ways and plumb bob them.
No response to stupid answer of 5 footers grab more air? DA
5 footers may add 25% more stick issues if not solved with 4 footers

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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by Gary S » Thu May 03, 2018 7:03 am

No response to stupid answer of 5 footers grab more air? DA

Was this really necessary?

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Prototype
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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by Prototype » Thu May 03, 2018 10:22 pm

Gary S wrote:No response to stupid answer of 5 footers grab more air? DA

Was this really necessary?
The poor dude can't estimate the weight of a rudder? or it's affects ? or it's geometry?

What say you "not to my post but the poor guys problems"?

Editing post don't count in your goal to say nothing?
Last edited by Prototype on Thu May 03, 2018 10:56 pm, edited 1 time in total.

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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by diamondback0320 » Thu May 03, 2018 10:47 pm

haha gotta love it!

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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by diamondback0320 » Thu May 03, 2018 10:48 pm

all I've ever run is 4ft so can't comment on the 5's

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Re: Rudder help Please, 4ft vs 5 on 16ft boat???

Post by Gary S » Fri May 04, 2018 6:53 am

I guess I didn't say anything because I was trying to get in my mind what he was trying to do. If I read this correct he has two 4 foot rudders and he wants to put a single 5 foot rudder on. If this is the case I don't think there is going to be much change in the handling of the boat. That is only a opinion not from experience. If he is going to install 2, 5 foot rudders then I believe he will have better control and will not have to use as much rudder stick to control the boat. I also believe the boat will handle better at slow speeds. This is due to the fact that they have more surface area to grab and divert the air.

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