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Waterproofing for floor and stringers

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Anthony

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May 27, 2002, 7:45:44 PM5/27/02
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Hi,

I've got a major project where I'm replacing the floor, stringers, transom
in a 1989 Searay 190 Bowrider. I'm going to be posting several question
related to this project, but I'm trying to separate the questions into
discreet topics to keep the thread on topic. Thanks for your patience.

Basically, I've ripped out all of the wood (if it was wood, it was rotten)
and foam. Now, I've cut most of the wood for replacement. The wood that
I'm using is CCA treated exterior plywood. It has been kiln-dried to remove
moisture. My plan is to waterproof each piece individually before
installing back in the boat. After installation, I will replace the foam
and refiberglass the whole floor and transom assembly. Most sites mention
the use of epoxy resin for waterproofing.

My questions are:

1. Is it a good idea to waterproof the stringers and floor prior to
installation or am I wasting my time?
2. If I should waterproof, what should I use? Has anyone tried standard
polyurethane for this purpose and what were the results?
3. Are there some "best practices" that people follow when doing this?
4. How did water get into the stringers and floor in the first place? It
appears that Searay used standard interior grade plywood and waterproofed
them prior to assembly. However, when I pulled up the floor, everything was
rotten. I've heard the term Osmosis used a lot. How do I keep all of my
hard work from going down the drain in a couple of years? If I do this
once, I want to do it right and NOT have to do it again.

Thanks again for your help,
Anthony


MastNMate

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May 27, 2002, 9:54:17 PM5/27/02
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Anthony;
You've taken on a big project. The original wood rotted because the
fiberglass and the resin bond was not sufficient and moisture got to
it.Waterproof the new wood with penetrating epoxy and make sure your fiberglass
and resin bond is a good one.-----------good luck
GaryW http://www.mastmate.com

David Carnell`

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May 28, 2002, 7:37:40 AM5/28/02
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Nothing waterproofs wood and penetrating epoxy thinned with a lot of solvent-CPES
is especially poor at it.

Check <http://www.epoxyproducts.com/> THe boating/marine page has some interesting
results with Aluthane®. Forest Products Lab got surprising results with the
aluminum paints of the day a good many years ago.

Scott Downey

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May 30, 2002, 8:52:10 AM5/30/02
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CCA treated wood wont rot, so why worry about the water?
You could just paint them to keep away some of the water.
"Anthony" <ant...@NOSPAMnc.rr.com> wrote in message
news:IyzI8.21035$Ir1.1...@twister.southeast.rr.com...

Scott Downey

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May 30, 2002, 8:57:51 AM5/30/02
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Dont worry about new rot with the CCA treated plywood. I redid one of my old
glastron 18 footer using 3/4 CCA plywood. I did not paint or epoxy or
anything. There is no rot now for more that 5 years. The CCA wood is rot
proof for 40 years or more. If you want to keep the wood drier an ordinary
coating of latex paint will do the job after you attach the wood members to
the hull.
You should also consider adding in additional pieces for strength if you
want a stronger off shore boat. Now that it is apart is the time to make
sure the original design is sufficiently strong.

"Anthony" <ant...@NOSPAMnc.rr.com> wrote in message
news:IyzI8.21035$Ir1.1...@twister.southeast.rr.com...

Scott Downey

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May 30, 2002, 9:02:05 AM5/30/02
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Also use stainless steel screws everywhere. You can buy boxes of stainless
deck screws at the Home Depot. If you check out the screws at Lowes you may
find them with thinner shanks that will twist off under pressure, the HD
screws are much better at least in this area of Norfolk, Newport News.

"Scott Downey" <sdow...@worldnet.att.net> wrote in message
news:rApJ8.168$p3....@sydney.visi.net...

Anthony

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May 30, 2002, 8:26:58 PM5/30/02
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Thanks for the info. I was thinking about glassing the planking and
everything that was exposed anyway, so it sounds to me that spending the
effort and money to glass the stringers and floor that would be incapsulated
under the planking by fiberglass would be a waste. Does anyone disagree?

Thanks,
Anthony


"Scott Downey" <sdow...@worldnet.att.net> wrote in message

news:pEpJ8.169$p3....@sydney.visi.net...

Highlander

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May 30, 2002, 10:33:38 PM5/30/02
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Anthony <ant...@NOSPAMnc.rr.com> wrote in message
news:mrzJ8.32004$Ir1.1...@twister.southeast.rr.com...

> Thanks for the info. I was thinking about glassing the planking and
> everything that was exposed anyway, so it sounds to me that spending the
> effort and money to glass the stringers and floor that would be
incapsulated
> under the planking by fiberglass would be a waste. Does anyone disagree?
>
> Thanks,
> Anthony
Okay..I'll disagree.
Unless there was no way out of it...I wouldn't encapsulate any of it.
assuming you've made that decision already..I'd encapsulate everything.
After all..at that point the wood is just part of the substructure of the
fiberglass.
As for the fasteners. If you're staying on all fresh water stainless
fasteners may be okay..otherwise..Monel or silicone bronze is the only
choice


@goeshere Thomas Bloomer

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Jun 1, 2002, 6:13:34 AM6/1/02
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>>Okay..I'll disagree.
>>Unless there was no way out of it...I wouldn't encapsulate any of it.
>>assuming you've made that decision already..I'd encapsulate everything.
>>After all..at that point the wood is just part of the substructure of the
>>fiberglass.
>>As for the fasteners. If you're staying on all fresh water stainless
>>fasteners may be okay..otherwise..Monel or silicone bronze is the only
>>choice

In general, I agree with the Highlander's disagreement :-) But I don't see
how you can replace stringers without fiberglassing them to the boat.
Regardless of how you do the work, you will not keep water from under the
deck. If you encapsulate it all in 'poxy and a layer of glass, it will be
stronger and last longer, but water will still get in somewhere . . . always
does, always will . . . that's its job ;-)
--
Tom Bloomer
Hartly, DE


Kosmas Dtrimaran

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Jun 19, 2002, 9:58:43 AM6/19/02
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Isn't it true that certain kinds of hard wood need to breath and if
you seal them up then their qualities deteriorate?

KoZ

"David Carnell`" <davec...@att.net> wrote in message


> Nothing waterproofs wood and penetrating epoxy thinned with a lot of solvent-CPES
> is especially poor at it.
>

> MastNMate wrote:
> > Anthony;
> > You've taken on a big project. The original wood rotted because the
> > fiberglass and the resin bond was not sufficient and moisture got to
> > it.Waterproof the new wood with penetrating epoxy and make sure your fiberglass
> > and resin bond is a good one.-----------good luck

--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

Pat Ford

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Jun 19, 2002, 1:12:36 PM6/19/02
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On Wed, 19 Jun 2002 13:58:43 +0000 (UTC), "Kosmas Dtrimaran"
<kosm...@yahoo.com> wrote:

>Isn't it true that certain kinds of hard wood need to breath and if
>you seal them up then their qualities deteriorate?
>

The discussion about whether to paint or not to paint in the bilge is
an old, old argument. Some say paint the wood ("Save the surface and
you save everything.") and some say not to paint-coat the surface in
linseed oil and let the wood "breathe."

I usually painted, but I don't have strong feelings one way or the
other. Painted bilges may look neater if you are, like me, overly
generous with the bedding compound and other goops.


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