Overly Bow Proud?

OLD BAY

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This is my boat at just under 22kts.
Does she look overly bow proud? Or can the stern be too low in the water at speed?
She has no lifting rails, she does have trim tabs (retracted in this photo). The tabs will bring the bow down, but at the expense of ride and some speed (1/4 kt).
I ask out of (mostly) curiosity and because you have to be 6' tall to see over the bow at speed. I wondered if lifting rails would bring the bow down and maybe even get me a little extra speed? Or just stick with the trim tabs.
thanks
old-bay-albums-wasque-32-picture474-image.jpg
 
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petrel

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I guess a rope under the stern would be too ghetto for that vessel. Have you tried it?
 

OLD BAY

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I've only learned about the rope method this winter (from this site). I plan to try it in the spring, I figured 1/4" line to start. Does that have the same effect as the tabs, lift and drag, or is the rope all drag?

Thanks for the input.
 

Chum Pot

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At first I thought I might see a nice mermaid shot with the title of this post. :wink:
Did you have a fully belly of fuel in this picture?
I find my Parker is ass heavy too, but can tab and tilt OB to perfect the ride. When fully loaded the tabs are just a part of life especially when slowing down. I would investigate if any weighting in the boat is causing this, could any item batteries, gens, water/fuel tanks)that is adding weight be moved forward. You might also investigate having fixed planing tabs installed, or investigate props as they can really effect lifting the stern. Do you have 3 blades or four blades I agree she is riding up and she is a beautiful boat.

PS: please tell me more about the rope around the stern technique
 

OLD BAY

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Same principal as wedges, tabs to a small degree. More akin to the QL system of tabs where there is a vertical obstruction creating a difference in water pressure.

Ok, thanks. This site is extremely useful. I'll experiment with the rope around the stern, if for no other reason than to learn something new about the boat. Then I'll likely take petrel's advice and use the tabs more!
 
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on the boats we have done it on, planning hulls. It tells us if tabs are worth while. I can;t see it being different on a de.

have you thought about stern rails

here's an ugly picture but will give you an idea

foxsea-stern-closeup-600.jpg


You might get better results with lifting the ass up on its own, then forcing the ass up with tabs.

also weight displacment, you could try moving more weight up front, see if that helps.

different prop, with LESS rake will bring the bow down as well
 

OLD BAY

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At first I thought I might see a nice mermaid shot with the title of this post. :wink:
Did you have a fully belly of fuel in this picture?
I find my Parker is ass heavy too, but can tab and tilt OB to perfect the ride. When fully loaded the tabs are just a part of life especially when slowing down. I would investigate if any weighting in the boat is causing this, could any item batteries, gens, water/fuel tanks)that is adding weight be moved forward. You might also investigate having fixed planing tabs installed, or investigate props as they can really effect lifting the stern. Do you have 3 blades or four blades I agree she is riding up and she is a beautiful boat.

Thanks for the comments. The stern is pretty light, I moved everything I could ahead of the engine (batteries, fresh water tank and storage in the bow. She has no generator. This photo is with 1/2-2/3 full fuel tanks, but they straddle the engine.

The prop is 4-bladed.
Thanks for the compliment on the boat, she is a member of the family. We brought her back from decades of neglect.
 

OLD BAY

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have you thought about stern rails

You might get better results with lifting the ass up on its own, then forcing the ass up with tabs.

different prop, with LESS rake will bring the bow down as well

Yes, I was wondering if stern rails might help. I heard placing them at the radius where a straight egde falls (with the other end of a straight edge on the bottom of the keel) would be the way to go.

My wheel has very little, if any rake. But I plan to get it reworked and measured this spring so I'll find out the specs.

I appreciate the input.
 

BillD

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Thanks for the comments. The stern is pretty light, I moved everything I could ahead of the engine (batteries, fresh water tank and storage in the bow. She has no generator. This photo is with 1/2-2/3 full fuel tanks, but they straddle the engine.

The prop is 4-bladed.
Thanks for the compliment on the boat, she is a member of the family. We brought her back from decades of neglect.

A very pretty pretty boat. As a family member you gotta keep her off the "auction block" !;)

Couple of comments.

1. I spoke with the owner of a 29 H&H DE boat with 440 Yanmar power. He "had" a similar problem with the bow of his boat riding high when he put the power to her. The boat was built with full length lifting rails. The 2nd season he had her he installed "stern rails" (not sure if like jersey suggested). The rails "solved the problem". QL tabs would have done the same.

2. The helm placement on your beauty causes much of the problem. You are simply "too far back" on the elevated plain. Not much you can do about that.

I'd try the stern rails.

FWIW, (and it's not much) :D

Bill D
 


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