Flotation foam for buoyancy... Neccessary evil or just a bad idea?

xbskt

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My Salty Boats 14 ft. skiff project originally had foam for buoyancy under the seat in the bow. I am not a fan of foam but if it was there originally perhaps I should put some back in. A larger outboard on the back and a small anchor chain locker in the front for a Danforth on the foredeck are the only changes from the original layout I am planning so weight will be about the same.
Do I really need the extra lift or go without to avoid the assumed eventual wet foam mess buried in the bilge.
I would use pourable 2 part closed cell I have on hand leftover from a repair on my whaler so cost isn't a factor. I jut don't want to do it if not necessary.
There is also my lack of understanding of how much bouyancy this foam provides over and above the hull form but perhaps that is for another thread.
Thanks for any feedback.
Jeff
 

Genius

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my vote is no foam. Archimedes would agree. The foam adds no extra buoyancy, just if it sinks... it stays swamped and barely floating.
 

RobBaker

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I hope you never need it, don't need those life jackets either I guess :)
 

Diesel Jerry

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RobBaker

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Your comparing a 14' skiff to a large offshore commercial boat, real bad argument.
When I capsize in a 14' boat I'll take a Whaler any day over a 14' skiff without foam.
 

Diesel Jerry

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Quik Fix 16

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Air pockets are the best flotation. When building my skiffs, I got a shop visit from the CG. I was pretty surprised to hear his suggestion for flotation. I did it without a problem and at very little cost. PM if you want to know. My boats passed their tests.
 

Curmudgeon

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Required by USCG for I believe boats less than 20 feet and some very low horsepower if I remember corrrectly.
 

sailor of fortune

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Plastic litre soda bottles with top screwed on in closed flotation compartments. Cheap,light weight and usually free. Won't soak up and get heavy/ nasty.
 

WoundUpMarine

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Last edited:

WoundUpMarine

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Quik Fix 16

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Plastic litre soda bottles with top screwed on in closed flotation compartments. Cheap,light weight and usually free. Won't soak up and get heavy/ nasty.
And the winner is! Cover with a wet layer of fiberglass so they don't bounce around and make a banging noise. Required on boats 20' and under. Don't think a homemade requires any and know a commercial boat does not. Rebuilding your boat, do what you want.
 

Kenneth

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The last boat i rebuilt was a 69 John Allmand 25 and i foamed the entire bottom of the boat with 2lb close cell foam, enough to float twice the weight of the hull. Made the boat much stiffer and if i capsized 40 miles offshore it stay on top of the water.

69 john allmand 042.jpg
 

Blitzen

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I think some reserve buoyancy is always a good idea, it doesn’t have to be foam. Small racing sail boats use air bags. It would be comforting to know that if something happens the boat won’t sink. That is why I bought a Boston Whaler for my kids.
 

MAArcher

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Also air is more buoyant than foam. I will trust my air pockets over a bilge or compartment full of foam any day of the week. When that foam gets wet....and it will get wet just ask any Whaler or Mako owner....probably a few others it’s more of a danger than an aid.
If air pockets stay water tight then why would foam in the same space take on water?

I like the idea of the coke bottles. I wonder if the best bet for emergency buoyancy wouldn't be to fill the bilge with as many bottles as will fit, and then secure them in place with foam so the bottles don't move around and wear holes in them?
 

Genius

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If air pockets stay water tight then why would foam in the same space take on water?

I like the idea of the coke bottles. I wonder if the best bet for emergency buoyancy wouldn't be to fill the bilge with as many bottles as will fit, and then secure them in place with foam so the bottles don't move around and wear holes in them?
....time is not your friend and the answer to your first question.
 

Genius

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I use ping pong balls, just kidding...i don't.

Did you see the myth busters episode where they raised the vessel using ping pong balls?
 

MAArcher

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I was thinking about buoyancy when I first got my boat and was daydreaming of a way too rig something like car airbags to the boat. I searched online and found someone already makes something that looks like a spray rail that deploys bags in an emergency. They were pretty expensive and only for bigger boats though. Hopefully one day the become more available.
 
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