boat rot...wet foam prevention.

[oops!]

IF YOU WANT TO KNOW ABOUT FOAM.....THIS IS THE THREAD

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this question has been bugging me for a few months now.....

once the foam is compleately sealed in the floor/hull/stringers......the only way for the foam to get wet is condensation.....

this condensation will also rot the floor out from underneath.....

how can we avoid this?????

do we forget the foam and go air bladder with breathing holes in the floor?

bondo says "the foam is just there to rot the stringers" i know this is tounge in cheek, but he's right.

redoing foam every twenty years is not a fact of life im prepaired to live with.

lets have it...!!!!

how do we get around it??.....safely

oops

 

[Don S]

Re: boat rot...wet foam prevention.

The foam gets wet because of leaks, not condenstation. Which means it's NOT completely sealed. If the cavity is full of foam, there is no place for condensation to form.

 

[oops!]

Re: boat rot...wet foam prevention.

thats what i thought, if sealed and filled TOTALLY, there would be no place to form droplets...

but 2 different major builders/manufactures told me it was mostly caused by condensation...

hot day......cold water...hull in water.....

now im really confused

 

[tashasdaddy]

Re: boat rot...wet foam prevention.

the best prevention, is pay attention to your boat, fasteners and seals. most rot begins, under seats, where screws have been put thru carpet, without sealing. keep the bow high when stored and the boat covered.

 

[wildmaninal]

Re: boat rot...wet foam prevention.

If you want to see a boat that is more rot resistant then others copy and paste this link
"http://www.outdoorlife.com/article.jsp?ID=21009215&typeID=425&categoryID=265"and scroll down to TRITON 176 MAGNUM toward the bottom. Now keep in mind that the hull is aluminum. I was wanting to see about putting an aluminum floor in one of my boats with possibly using aluminum 2x3s for the stringers but nobody on here seemed to think it would be a good idea, I can understand the hull flexability and possibly added weight and I would be putting this in a fiberglass hull.

 

[Lou C]

Re: boat rot...wet foam prevention.

Foam or no foam, the main thing is to seal any screw holes keep water from pooling on the deck, make sure you have good covers and use em, and try to have air circulation during winter storage especially. As long as you have 'glass over wood, you will still get rot if water sits on an unsealed deck area for any length of time.
I vote for foam to save your life one day (possibly, let's hope you never need it.) and good maintenance habits to save your floor.

If you had a deck on the back of your house, that had water sit on it long enough, with deck screw holes in it, unsealed, and you threw a carpet over it, that wood would rot, even with no foam under it.

 

[oops!]

Re: boat rot...wet foam prevention.

link didnt work.......pm.......

i agree with all......

but can we come up with a creative solution?

re-invent the wheel so to speak?

ideas?

 

[tashasdaddy]

Re: boat rot...wet foam prevention.

the solutions has been solved, they are now making all fiberglass boats, not wood cores. My 23' Chris Craft deckboat is all glass.

 

[Ronnie_P]

Re: boat rot...wet foam prevention.

what if you inserted a plastic liner where the foam was to be poured? My stringers were fiberglass over wood. The combination of fiberglass and the plastic liner may all but eleminate and absorbtion other than where holes are drilled. Also I am planning to use 1/2 foam 4/8 laminated (liquid nailed) with 1/8 sheet fiberglass (used for wall covering), or 1/8 wood (possibly ceder) and fiberglassed over. After that I will insert a sheet of plastic between the hull and stringers. Next I'll install the subfloor piece on top with plastic underneath enclosing the entire thing. After drilling holes and pooring the foam, i will level the holes and and fiberglass over them. This is what I have come up with to eliminate rot and absobtion. Of course the transom will still need to be wood for strength. What do you think?

 

[oops!]

Re: boat rot...wet foam prevention.

hey ronnie

welcome to i boats....
as you can see this site is filled with pros willing to share....amatures with good advice/opinions...and first timers that have no end to questions....(thats a good thing)

i thought about what you are suggesting....the only problem is the foam will not fill every LITTLE void when incased in plastic......it needs to be everywhere....every millimeter of space. the plastic will not allow that to happen.....condensation will occure, moisture will get trapped...and ...rot....
if you do go the foam route....just fill it all without the plastic....you might want to coat the bottom of your floor with resin/lite glass as a barrier.

just remember as mentioned above...ANY DECK PENETRATION.....screw...staple..must be sealed....

if i do go the foam route...and i probablly will...im going to do a flo cote after the stringers are glassed in..on the whole bote...then the same after the floor just to make sure the whole sha-bang is sealed.....

restoring a bote is an imperfect science...with many types of ways to do it...the best way...is the way you feel you can do properly without compromising structureal/saftey/and longevitey issues....

cheers
oops

 

[azlakes]

Re: boat rot...wet foam prevention.

... invent foam impervious to moisture

 

[Bondo]

Re: boat rot...wet foam prevention.

bondo says "the foam is just there to rot the stringers" i know this is tounge in cheek, but he's right.
but can we come up with a creative solution?
re-invent the wheel so to speak?
ideas?

Ayuh,...... No jest there,.... I'm as Serious as a Heart Attack........

Some of you are familiar with the Wellcraft 50' Scarab I'm helping with,......
That boat has Absolutely No Foam in it,.. Anywhere.......

Those Crazy flatbottom V-drives,+ Jets that are pretty popular down in Havasu,..??
No Foam in them boats either,... Maybe an old trucktire innertube stuffed up under the bow,...
But that's just to find a place to tie the rope when it sinks....

The way I'll get around putting Any foam in My boats is,......

Start with a hull that is Solid enough, or Make it that way,...
Then make Sure that there are limber holes thru all the subframing of the hull, so it can Drain down to the transom for pumping,......
Make sure there's enough Venting of the bilge areas. so they can Dry after they Drain....
There has to be a Quality bilge pumping system built,... I run 2 or more redundent self contained bilge pumping systems.....

And of course,... Make sure the PFDs are where they belong,+ are in good condition......

There's No Such Thing, as a Waterproof Compartment in a Boat,.....Period.....
Foam or Not......

If, by chance that you are Run Over by a much larger boat, or Hit something, Hard,.....
If you survive the Impact,..........
Break out the PFDs,+ Do what ya gotta Do,.......

Btw,.......
Duct taping a Cooler shut will float a pretty good sized load..............

 

[oops!]

Re: boat rot...wet foam prevention.

you really gave me somthing to think about there bondo...

by running a flo coat......(thats what that black stuff i asked about was)

it will give the hull the rigidity that the foam would have added..plus it is an impenatrible barrier to the glass.......place a few inner tube like thingies in the voids...add a few fans for ventelation and drain holes.....and done....

any ideas on the calculations for air/weight? ...ie how much innertube thingies?

cheers...
oops

 

[Bondo]

Re: boat rot...wet foam prevention.

any ideas on the calculations for air/weight? ...ie how much innertube thingies?

And of course,.......Make sure the PFDs are where they belong,+ are in good condition......
Break out the PFDs,+ Do what ya gotta Do,.......

Ayuh,....... I think PFDs are rated at around 300lbs......Each of course..........


Round #s,... a gallon of air floats about 8lbs,..... a cubic foot of air floats about 64lbs........I Think....

 

[Bob_VT]

Re: boat rot...wet foam prevention.

Ayuh,....... I think PFDs are rated at around 300lbs......Each of course..........


Round #s,... a gallon of air floats about 8lbs,..... a cubic foot of air floats about 64lbs........I Think....

I sense us going to the plastic bottles again.... with vents to dry things out.

 

[oops!]

Re: boat rot...wet foam prevention.

bottles rattle....even when stuffed...they will still move...

im thinkin...innertube...sliced....then weld the ends shut so it takes on a hot dog shape....if the welding is done properly...it should hold air for about 10 years....with the proper acess...it could be changed easy enough.....

4 of them puppies on each side...with one in the bow.....might do it.....

heres a dumb question.....if air is compressed to say 30 lbs...like in an inner tube...will it be more bouyant than a non compressed equivalant container?

oops

 

[erikgreen]

Re: boat rot...wet foam prevention.

Nope... buoyancy is based on volume of water displaced.

So the best way for a given volume of air to provide buoyancy is for it to be completely uncompressed and enclosed so as to displace water.
Edit: To be clear, the compressed air in a container of a given volume will have the same buoyancy as uncompressed air in the same volume, but since there's more air in there it's heavier (marginally) and has a tendency to try to leak

I think you guys are following an interesting path, but here's another idea... include an inflatable life raft on the boat It'll help you survive better than the bow of a hull pointing out of the water, and it'll provide much more protection in case of bad weather or cold water.

Logically speaking, you have one of two design possibilities: A sealed system of foam, where no water can get it (hard to make perfect) or a system that assumes water will get in and provides a way for it to get out and dry. The second method is what all larger boats use, and what makes sense to me.

For myself, any foam I remove I'm not putting back. It's not even legally required on boats over 20ish feet long, and its negative effects outweigh the built-in floatation advantage. I'd rather just carry multiple PFDs and a VHF, and a life raft when I can.

Erik

 

[oops!]

Re: boat rot...wet foam prevention.

thanks erik

but here's another idea... include an inflatable life raft on the boat

actually there will be a raft on board.....i wont be able to pull it up on shore any more cause the bote is gonna be pretty...not an old lookin scow that i didnt care if it took a beating.....so the raft is gonna be used for ship to shore when we are camping......

im gonna be putting in several high volume air compressors for different things, including one item that i an inventing....(thats what the fantasy gadget thread was all about)....but thats a secret....it will be pretty cool when done....

i just dont wanna regret not putting flotation in one day

 

[mspring]

Re: boat rot...wet foam prevention.

On my fiberglass 20 footer the hull cap kinda forms an area of about 8" tall and 6" wide all around the top of my hull. Why cant I run plastic conduit in there to run my wires through and pour it full of foam. Then I would not have any below deck to worry about. Would that be enough for floatation?

 

[Bondo]

Re: boat rot...wet foam prevention.

A sealed system of foam, where no water can get it (hard to make perfect)

Ayuh,.......

The answer to that is about 2/3s the way down My 1st post on this subject,........

There's No Such Thing, as a Waterproof Compartment in a Boat,.....Period.....
Foam or Not......