structural integrity compromised

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gpm
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structural integrity compromised

Post by gpm »

Boat is a 1976 u14 Valco 62 inch beam with 3 bench seats. Will removing the middle seat compromise the integrity of the boat in a significant way? I am 83 and dont like to step over the beach when i move around in the boat because of a compromised balance system incident to age.

Jerry

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DaleH
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structural integrity compromised

Post by DaleH »

Well the short answer is - yes ...

But the long answer is - how will YOU use the boat? If on ponds w/ low hp OB motors and not slamming around into boat wakes or a steep chop ... then have at it. You could also just cut a walk way out of the middle, like some factory hulls do.

But with such a seat removed and IF slamming into waves, or driven hard & fast by a big OB motor and into a hard chop or heavy sea state all the time, then yes - the hull could collapse or 'oil can' on you. See the photo.

I have even seen damage 1/3rd of the way back from the bow on fiberglass CCs that were poorly designed in the stringers and the bow wanted to 'fold back on itself', from all the repeated slamming into seas. One could see stress cracks up to 6' long that you could drop a dime into and they'd stand up!

....
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gpm
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structural integrity compromised

Post by gpm »

Thank you DaleH. I will not remove the full seat BUT what if i only remove a two ft section from the middle of the seat. This would allow ample passage for my big feet. The seat is viveted to the bottom of the Valco. After removing the rivets from a two ft section of the middle of the seat and applying proper sealing technique do you think the remaining rivets and seat will maintain the strength of the sides? I am running the boat at 17 to 20 mph with a 25 hp OB and will always spend some time during the day in wind and chop and often running in the waves of Wake boats and their surfers.

Weldorthemagnificent
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Re: structural integrity compromised

Post by Weldorthemagnificent »

A lot of folks who remove the middle seat, build rod storage along the sides. That lends rigidity to the sides.

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nytebyte
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structural integrity compromised

Post by nytebyte »

You could also take a grinder to cut the opening and leave a inch or so on the bottom of the seat area that you removed and build a floor over it for a walkway. That way you would not need to remove the bottom rivets and it may help with the strength.

gpm
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structural integrity compromised

Post by gpm »

Thank you Waldor. Hadnt intered my mind to do that but then not much does.

Jerry

gpm
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structural integrity compromised

Post by gpm »

Nytebyt, U R awesome. I will fly that past my helecopter mechanic and fishing partner. Never pass up an opportunity to partner up with a helecopter mechanic, they are useful and inovative souls. Try to find one that enjoys fly rods, indicator fishing and large trout. Did I spell your name correctly, probably not?

Jerry

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DaleH
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structural integrity compromised

Post by DaleH »

nytebyte wrote: 24 Nov 2021, 11:47 You could also take a grinder to cut the opening and leave a inch or so on the bottom of the seat area that you removed and build a floor over it for a walkway. That way you would not need to remove the bottom rivets and it may help with the strength.
^^^THIS!^^^ No need to remove any rivets if one doesn't have to! Even a cheap mat or or other over that areas works.

FYI, boat stores carry a piece of rubber trim (with metal insert, so it 'grabs' the material affixed to) in lengths that are white or black, and shaped like a tall 'U', that you could use on the cut-off seat ends to spare somone from the 'sharp' edges.

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maintenanceguy
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structural integrity compromised

Post by maintenanceguy »

I might install somethign like this, bent from round or square tube. You would have something to step over unless you can install the horizontal bars below the finished floor. This would resist the outward forces on the sides of the hull and you can install small seats on either side.
hull_reinforcement.PNG
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-Ryan

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BAY BEAGLE
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structural integrity compromised

Post by BAY BEAGLE »

Saw this modification on a flat bottom. It was on one of the many sites I have visited, to get some ideas from.
Boat5.jpg
Boat8.jpg
Boat11.jpg
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- A FLATLANDER -

gpm
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structural integrity compromised

Post by gpm »

thanks for the responses. The solutions look good to me and are well illustrated. I think we can do that.

Jerry

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maintenanceguy
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structural integrity compromised

Post by maintenanceguy »

The notched bench seems like it's a bit flimsy to me. I'd worry about the seat flexing in the red circle.

I would cut along the yellow lines instead to leave more meat and add some reinforcing (blue) with a piece of angle or square tube.

Not much more work but a lot stronger. In my opinion.
bench_seat.png
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Last edited by maintenanceguy on 25 Nov 2021, 07:12, edited 1 time in total.
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DaleH
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structural integrity compromised

Post by DaleH »

If going the 'notch' route, use rounded corners, not sharp corners, to avoid stress risers!

gpm
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structural integrity compromised

Post by gpm »

DaleH, I appreciate your sticking with me on this. Those who have responded have all brought me closer to where I need to be on maintaining the integrity of the sidewalls of this boat on the way to making me a safe passage way from stern to bow. I appreciate your intensity, DaleH.

Jerry

gpm
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structural integrity compromised

Post by gpm »

I have found a 1998 crestliner 1650 fish hawk with a 20 hp 4 stroke Merc with open passage one end to the other. If I elect not to modify my u14 valco as we have been talking about and purchase the crestliner do any of you have an opinion about the 20 hp merc being grossly underpowered for the boat? Owner indicates 20 mph with 2 adults and 2 young grdkids.
jerry