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water bouy

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Wonder if these exercise steps could be used for flotation under the floor. I got a bunch for almost nothing. My first idea was small poly gas tanks but these are also made from hi density poly. Seems like every type of flotation I've checked out eventually absorbs water.

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Thanks Johnny. It was a bad idea though. The plastic is hard and not very light. I think I'll use the styro I take out of the middle bench and then hinge the floors so i can check on it and store stuff.
 
I was at my local auto store yesterday and we got to talking about our boats.
this young man that works there saves all the plastic empty oil bottles he can find and
washes them out and uses them packed tightly under his wood floor and seats.

not a bad idea when you think about it - will never absorb water, will always have
small air voids for ventilation and a neat way to recycle !!!
 
That's a good idear too. I'd like to see if I can find someone who could vacuum seal styrofoam. A guy on craigslist has a bunch of it in 12"x12"x20" blocks. Also thinking about using the front bench for battery storage and moving the foam under the floor. I'm sure you've seen this guys Lund which made me think about hinged floors:

https://www.correllconcepts.com/boat_conversion.htm
 
Back in the 1940s, when testing newly built sea-planes,
it was a traditional practice to put as many ping pong balls
in the wings and fuselage as possible.
Howard Huges chose to purchase every beach ball in Southern California
and stuff them into his new plywood airplane called the "Spruce Goose".
So, in reality, whatever holds air and will keep the craft afloat will work.......
Spruce Goose.jpg
 
Johnny said:
So, in reality, whatever holds air and will keep the craft afloat will work.....

Would seem like small rubber balls or lawnmower or wheel barrel inner tubes would be able to be crammed in the recesses and shot full of air, within reason, should work.

I saw on a wood boat forum where the guy used small soda bottles and just duct taped them together hidden in false compartments. He claimed he couldn't sink the boat even with the plug out.
 
The previous owner of the new to me Alumaweld removed all the water saturated foam flotation out from under the deck.
I waited until the local Dollar Store stocked the pool noodles so bought a couple of boxes yesterday.
There will be some who has pro or con on using noodles but based on many posts I've read from various forums, noodles are great alternative flotation material.


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I have had mice 'winter' in my boats. I use moth balls, but still get them. They like to chew up foam or anything else soft. I like the idea of hard sided air chambers!
 
Everything that floats, including a sealed seat chamber with nothing but air inside of it, works.

The constant problem seems to be...once water finds its way inside, does the floating material absorb the water, or repel it (at least for a while).

One additional consideration is the weight of the object used. If one were to place lightweight styrofoam in one cavity; sealed milk/pop bottles in another; and a rubber innertube in a third cavity...the sytrofoam/bottle/rubber tube that weighs the most would produce less flotation when ultimately submerged.

That's probably why we find styrofoam in so many boats, even though it will, ultimately, absorb water.

I read someplace that syrofoam, painted with a good quality latex paint, (for some additional waterproofing) did a very good job over time. Makes sense to me.

richg99
 
Pool noodles will deteriorate with heat and absorb water. We use them at our gun club and even the ones not exposed to sunlight eventually get water logged
 
As I was trying to find a someone who does commercial packaging I was told the bags you store clothes in will hold a vacuum seal and all you need is a vacuum cleaner.

More digging found big freezer bags might work. Fill with styro and submerge in a bait tank till the air is out and seal. As long as you have access you can check each one for leaks.
 
I used both rigid foam sheets and poured liquid urethane foam in my build. I've seen many assertions that any foam will absorb water, and to an extent that is true, but it has a lot to do with how long you allow your foam to sit in water. A closed cell foam won't absorb water, at least on a short term. Closed cell jsut means that the bubbles that make up the foam haven't burst and thus won't allow water in; as opposed to open cell foams that have burst bubbles and will soak up water, like a sponge. However, water is the universal solvent, and if you let your flotation compartments fill up with water and the foam to sit in the water, over a long period of time it will eventually break down the foam. This is quicker in cold climates where you experience freezing over the winter. The water freezes and ruptures the cells of the foam, then thaws and absorbs into the now open cells only to refreeze and rupture more cells.

The best way to combat this is to make sure your foam stays dry...at least until you need it to float your boat. A majority of my rigid foam was installed under the nose of my boat on the upper deck, which will keep it out of the water. For my liquid urethane foam, I lined the bench I poured it into with plastic sheeting to provide a barrier between the foam and any water that made its way into the bottom of the boat. I also made sure the limber holes through the bench were clear by putting sticks through them, so that water can drain away to the bilge plug. I always store my boat with the nose as high as possible and the bilge plug out; that way if water does get in, it will drain away from my foam and harmlessly out the bilge.

As an aside, the plastic lining came in very handy when I inadvertently used an expired urethane foam that didn't expand to the proper density. All I had to do was lift it all out wrapped in the plastic sheeting; I'd hate to think what I would have had to do to get it out if I hadn't lined the compartment.

Richg99 is right, anything that will displace water in a large enough volume to float your boat will work for flotation. Foam provides a more resilient flotation, whereas a sealed compartment or 4 sealed milk jugs have a greater possibility of failure. A foam has a lot of small closed cells and even if you damage a block of foam (break it in half, stab it with a knife, etc.), it will still provide significant buoyancy. Whereas, if you poke a hole into a sealed compartment filled with air, it will lose all it's buoyancy, and poking a hole in one of the 4 milk jugs will result in losing a full 1/4 of your buoyancy. I think that is why USCG doesn't allow manufacturers to used large sealed buoyancy chambers to meet their flotation requirements.

As to mice, I've heard that the pool noodles (polyethylene) doesn't get touched by rodents, but I haven't had any experience with that myself.
 
The Spruce Goose! It was the largest plane ever built in it's time. It was trumped shortly after when Oleg Antonov started building aircraft.
 

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