Rudder alignment question

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rocklobster

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Apr 7, 2007
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My rudder alignment is way off because the previous owner removed it to do some Glass work and didn't put it in correctly.

I've had different opinions from people who I consider very knowledgeable about boats.

Regarding rudder alignment on a 330 Sea Ray Sundancer. Do you think they should be (when measured between the edges) :

A. narrower at the bow edge and wider in the stern edge?
B. wider at the bow edge and narrower at the stern edge?

I spoke to Sea Ray and the one person I spoke to said "B" but he didn't seem knowledgeable about it and but spoke to someone else at the factory. I'm not convinced something got lost in translation, probably on my side.

I would imagine there is only one correct way considering how water flows of the back of a Deep V hull. I know it doesn't flow straight off the back at Cruise

Thanks, Joe
 
Hello Joe in CT,

Why don't you call a few of the local surveyors in CT and ask the question of them. Or, take a tape measure to the rudders of some of the boats at your boatyard and see what's up with them. The difference that you are looking for cannot be that great, but could have some affect on the way the the boat responds, and as long as you are addressing it, it may as well be as correct as you can make it.
 
The spec for my Tiara is 15 degrees inward (each rudder) which relates to your option B.
 
My understanding of this is that rudder toe is required to take up slack in the rudder linkages to prevent flutter. Some manufactures specify zero toe, but most specify some small degree of toe (4-8) degrees total (2-4 degres each rudder). As far as toe in or toe out, most manufacturers will specify which is most appropriate to a given hull. Generally, toe out produces stearn lift, while toe in produces stearn squat to minimal degree. Some manufactures have both rudder toe specs AND rudder tiller toes specs. If your rudders have been rebuilt, you may want to make sure the tiller arms are also within spec. Hope that helps.
 
You have to have them one way or the other otherwise they will flutter (vibrate). That said, A will tend to cause the stern to draw down when under power, B will tend to cause the stern to rise. Most boats I have worked with use B, my 36 ft Trojan calls for 5 degrees. If I were to rig yours I'd go with B at .25 inch difference. Unless you know your bow tends to plow, then use A, same .25 inch.
 
Dang! I learn something new everyday. It always leads to wanting to know more-like what's the call on my SRay 330DA? I've never seen it mentioned in their material. Because it has v-drives with all that weight aft I'd bet they would be stern lift.
 
Bliss I think your right, you need B. It's not that much lift but if you have to take the extra drag, which you do, you might as well get all the good from it you can.
 
Joe, Just contact Sea Ray and ask for the information. There always happy to help out Sea Ray owners.
 
Mine is "A" and as far as I know, factory set.
 
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