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  #1  
Old 06-16-2010, 12:35 PM
Timberwolf Timberwolf is offline
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Flybridges on a narrow beam?

Just wondering if anyone, experts or otherwise, has any insight here.
How narrow is too narrow?
How tall before the boat becomes uncomfortable in a rolling sea?
I ask these ? because I am pondering the idea of putting a flybridge atop my Bandido. I don't think it will happen, but I am researching the idea because it could add living space and a great view. Looking at the Skipjack 28, I see it's possible to put a flybridge on a small boat, but I am concerned that it will feel top heavy, or tippy. Opinions anyone?
For those of you whom are not familiar with the Bandido, it's a Glen-L design, 30' long with a narrow beam, 8' at the widest point, only 7' 4" at the transom, 22 degree deadrise. My boat is currently a shell, the deck covered in and the cockpit floor in place, it weighs a mere 2400 lbs. I expect finished, with a Volvo D6DPH 370, she will weigh in, dry, around 5,000.
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Old 06-16-2010, 04:32 PM
tunnels tunnels is online now
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Location: china is great and interesting !!
Hi
If you have a narrow boat then keep as much weight as low down as possible in the hull
Everything above the floor level make aslight weight as possible , decks interior and what ever else the fly bridge needs to be light weight and the bare minimum of weight up there , Also windage is another subject to consider the smaller you are able to make it the better . With some careful planing and thinking outside the square i am sure you would be able to come up with something of a boat that size !!
One boat company i worked had a flybridge on a 20 footer but the internal arangement for the boat was a little strange , but anything is possible . Even a small good looking dodger with a steering station and a sliding roof so you can stand on a fold out space with the flybridge steer station above the main steering station . But to make all this work it need to be considered NOW before you get to far on with what you are doing !! Light weight Ply wood would be the best material to build it from , Not thin ply but lightweight .For you deck and cabinsides etc weight you ply !! you will be amazed at the weight variations between sheets of the same plywood , Could even use laminated ply with a foam sandwich between and little to no frame work where ever possible .
Time to get the brain into thinking mode and thinking very carefully about where all the heavy bits can be placed to keep it all down low . Then how to make all the other bits as light weight as possible without sacrificing strength . Remember if you put shape into a otherwise flat panel it becomes more ridged !! Go have a look at door panels on any car and see how they are shaped and gain huge amounts of strength .
SHAPE = STRENGTH !!
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  #3  
Old 06-16-2010, 05:40 PM
apex1
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Different from the very interesting but meaningless truisms above I tend to say no, that seems to be too slender for a fly.

But without having the full data of the given design it will be hard to find a rocksolid answer. And then I am not the one able to calculate it properly (as the last speaker isīnt).

But why not asking the designer of the boat through Glen L ?

Regards
Richard
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  #4  
Old 06-16-2010, 07:11 PM
Timberwolf Timberwolf is offline
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Quote:
Originally Posted by apex1 View Post
Different from the very interesting but meaningless truisms above I tend to say no, that seems to be too slender for a fly.

But why not asking the designer of the boat through Glen L ?

Regards
Richard
I tend to agree, too slender. I have been on a 25' with a fly, it did okay, but that was one run on a calm day.
I am hoping those with direct experience could chine in with personal opinions.
Your suggestion about talking to Glen-L is a good idea.
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Old 06-16-2010, 07:30 PM
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Easy Rider Easy Rider is offline
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For a 50' boat flybridges are OK


Easy Rider
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Old 06-17-2010, 07:18 AM
tom28571 tom28571 is online now
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Its not only the narrow 8' beam on 30' that makes the Bandido potentially unsuitable for a flybridge. The hull is also a deep V, which makes it relatively tender compared to flatter hulls of the same beam.

Other than large boats, how many flybridges do you see on deep V hulls?
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  #7  
Old 06-17-2010, 07:19 AM
apex1
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Originally Posted by Easy Rider View Post
For a 50' boat flybridges are OK..Easy Rider

Even that is not true in every case (too broad the statement).

We had a 88ft design study of a (very slender) boat where the fly was a issue and caculated several times before the idea was abandoned finally! (as was the design, btw).

More hard data is required before any of the experts here will dare to make a solid comment.

Regards
Richard
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  #8  
Old 06-17-2010, 09:13 AM
WickedGood
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On a Clear Day you can see the Rhine from the top

While this is Knot Quite an 88 ft Design it certainly appears to be well past the 10 meter mark.

Dont see why you could not just slap up somthing like this here rig.

Might wiggle a bit on a windy day but hey, that just makes for some good fun after breakfast of Hog Jowels and a dozzen Boc Biers.

Be sure you tie it down good with some heavy duty duck tape




Fortissima Saccharomyces: Sounds Impressive, like its a new Specimen of Fish; Dont it?
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  #9  
Old 06-17-2010, 09:38 AM
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daiquiri daiquiri is offline
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Geeee! While I might be able to climb up on that stuff if just I managed not to look down, getting back to the ground would be quite a problem...
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Old 06-17-2010, 11:20 AM
Timberwolf Timberwolf is offline
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Quote:
Originally Posted by tom28571 View Post
Its not only the narrow 8' beam on 30' that makes the Bandido potentially unsuitable for a flybridge. The hull is also a deep V, which makes it relatively tender compared to flatter hulls of the same beam.
Okay, I'm convinced, not a good idea.
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  #11  
Old 06-17-2010, 11:24 AM
Timberwolf Timberwolf is offline
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Might wiggle a bit on a windy day but hey, that just makes for some good fun after breakfast of Hog Jowels and a dozzen Boc Biers.

Be sure you tie it down good with some heavy duty duck tape




Don't laugh, I have seen something very similar to this on a pontoon boat, actually floating no less, on a reservoir in N.C.
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  #12  
Old 06-17-2010, 12:28 PM
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yipster yipster is offline
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seat 2.95 some antislip and 1k for the remote control
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  #13  
Old 06-18-2010, 06:09 PM
Timberwolf Timberwolf is offline
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This is where I'm at.
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  #14  
Old 06-18-2010, 06:10 PM
Timberwolf Timberwolf is offline
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This is where I was thinking of going, key word "WAS".
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  #15  
Old 06-18-2010, 06:37 PM
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daiquiri daiquiri is offline
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I like that slim hull shape, if it was mine I wouldn't want to ruin it with that helmet... This boat was born to be an open (or convertible?) racer. If you need a closed cabin you can design some low-profile streamlined shape which will fit the general sporty style of the boat. But not so high as the one in the second photo. It just doesn't belong there, in my opinion...
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