Flared Bow on C19

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Cracker Larry
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Re: Flared Bow on C19

Post by Cracker Larry » Fri Dec 03, 2010 9:18 am

I wasn't saying they were the same thing, just that to me they appeared to be the same style of boat
Similar. I was just correcting this
But again Larry that is on a 50-75' hatteras
twin 1,400hp diesels and pushed that large boat to 41knts while burning about 20 gallons an hour or something like that. I don't remember the exact numbers, but it was enough to tell me if I had one given to me I couldn't afford to pull it out of the slip :lol:

Still, a boy can dream can't he
Better dream larger, that boat burns closer to 200 GPH than it does 20 :lol: Richards little Pursuit with twin Yamaha 200s burns over 20 GPH. I was captain of a Hatty 50, fishing out of Ft. Lauderdale Mariott for about a year. She had twin 600s and burned nearly 100 GPH at cruise speed. That was in the 1970s, when diesel was about $.60 a gallon :lol:


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Re: Flared Bow on C19

Post by jacquesmm » Fri Dec 03, 2010 9:36 am

In some rare conditions, the flare will deflect sprays but not under normal operations.
The picture a few posts above should be compared to what happens to a boat without flare.
In that picture, one can imagine how much energy is absorbed by the flare when the boat hits a wave that way. She must be stopped or almost stopped while a boat with no or less flare will be wet but keep going faster, wasting less energy.
The comfort of the crew is another factor. The boat with excessive flare will decelerate brutally each time the flare hits a wave then accelerate until it reaches the next wave and so on. The one with no flare will keep going at a more steady speed.
Studies have been made of what the crew can take and I am certain that no crew will want to drive a boat as in the picture for very long.
That is why many modern fast boats are long and fine. They keep going steadily through the waves instead of fighting them.
Image
That's the antithesis of the Carolina flare :P
Then there is power and range. To fight waves that way instead of going through them will require more power, bigger engines and more fuel.
Bottom line, except for aesthetics, I prefer no flare.
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Re: Flared Bow on C19

Post by gstanfield » Fri Dec 03, 2010 9:51 am

Better dream larger, that boat burns closer to 200 GPH than it does 20
Yeah, that's what I thought I was typing :oops: The actual numbers on the boat I looked at was 185GPH, I knew it was close to 200 just a slip of the finger when I typed it :lol:

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Re: Flared Bow on C19

Post by JimmyB » Fri Dec 03, 2010 10:44 am

Interesting topic! Though it feeds the cynic and maybe other non endearing qualities within, I like it when physics meets aesthetics. That’s not to say aesthetics doesn’t play a significant role, as it does; particularly in marketing. It can also make you “feel better”, and that’s OK too.

For me, beauty is in the function and the form that follows. I’ve been contemplating the flair, more for utility of sale, than sail. At any rate, it’s not much of an issue at the moment. The HVAC system for the house I’m building is still in a warehouse somewhere and its chilly here in west central MN. I wish the only question for today was “to flair or not to flair”.

Best Regards

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Re: Flared Bow on C19

Post by jacquesmm » Fri Dec 03, 2010 11:50 am

Don't misunderstand, I am not against flare. I designed some of our boats with flare and flare has some advantages.
I did not mention resale value but that is a very valid point inf favor of flare.
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Re: Flared Bow on C19

Post by ks8 » Fri Dec 03, 2010 12:19 pm

I wonder if the flare is done just right, if it might actually soften the drop/splat, but I imagine it would be difficult to do this in a broadband way and still have a significant softening effect through a wide range of speeds and wave heights. An optimized flare probably would be more like a flare designed to optimally soften the ride for a particular avg wave height (and period) and a particular narrow range of speed, while unfortunately creating a stiffer ride and loss in performance at sea states and velocities outside of the narrow optimal design window. If you design too broadband, I'm thinking you will encounter more loss of forward velocity and more violent decelerations, and then accelerations, as J had posted. And it seems that there is too much unpredictable in sea states to design an optimum flare for *everyday*. The design of that posted picture somehow *intuitively* (?) appears to be broadband and not intended for acceleration comfort, but for spray deflection and real estate. It might also slightly mellow the pitching motion in a sea, as buoyancy, or at least deceleration resistance increases as the bow is pitched further down. The world of compromises once again. :)

You folks who tweak your engines with tuned pipes probably know what I mean, cutting angles to broaden the tuning a bit, or any hams know what I mean in terms of circuit or component *Q*. All that being said, yep, it does look cool. 8)

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Re: Flared Bow on C19

Post by Dan_Smullen » Thu Sep 19, 2019 9:22 pm

Intrigued to say the least. Chesapeake Bay and Outer Banks is where I fish, and where I intended to use my C19, and I really want to bomb around with a flared bow. It screams custom and bespoke.

In my 3D model, I’ve added a little reverse camber and 2” in width to station A, and slight reverse camber on the bow mold. Mocking up with luan or cheap ply will be worth the experiment.

I like Steven’s approach by leaving the upper panel long and wide, to be fit on the frame.

Cutting molds this weekend. Who’s excited!?!

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Re: Flared Bow on C19

Post by Fuzz » Thu Sep 19, 2019 10:12 pm

this will be interesting. Make sure to start a build thread and post a ton :D

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Re: Flared Bow on C19

Post by jacquesmm » Fri Sep 20, 2019 9:36 am

Send me your 3D model and I"ll see if I can help or at least give some advice.
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Re: Flared Bow on C19

Post by Marshall Moser » Fri Sep 20, 2019 10:21 am

Image

This is a "Down East NC" style boat. Almost a dory. Very low deadrise at the transom. Nearly vertical stem. Lots of flare.

I like the look of the flare too. I'll be following with interest. Be sure to post pics of your process.

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