Thread: Paint
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Bruce[_4_] Bruce[_4_] is offline
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Default Paint

On Fri, 16 Apr 2010 10:36:57 -0400, I am Tosk
wrote:

In article ,
says...

On Thu, 15 Apr 2010 04:04:12 -0400, I am Tosk
wrote:

In article ,
says...

On Wed, 14 Apr 2010 11:20:14 -0400, I am Tosk
wrote:

In article ,
says...

Dave wrote:
I'm building a 9 foot wooden flat bottom boat for myself and the kids.
It'
made out of 3/8" plywood from Home Depot and we're probably going to
use it
about every other weekend in the water. Where I'm at it's mostly salt
water
area (Gulf).

My question is:

Will normal Latex Exterior house paint will work?

best to seal with 2 coats of solvent thinned epoxy or moisture cured
urethane primer, then ext. latex....

paul - progressive epoxy polymers inc

With all due respect, that is not the way to go. I am going to assume he
used regular exterior ply and it is more vulnerable to moisture damage
than BS1088 or similar. If he coats it with two coats of thinned epoxy,
moisture that gets in (and it will) can not get out. Wooden boats are
best done old school with paint and sealer. A good wood primer, some
sandpaper, and a couple coats of acrylic based paint, he doesn't want to
use latex, at least on the outside, inside is ok...

Let the wood breathe and the boat will last a lot longer...

Scotty, just my opinion.

I think it depends on many things. did any scrapes or dings damage the
boat? Dragged it up on the beach and wore all the coating off the
bottom?

But your assertion that somehow moisture penetrates in through the
epoxy and can't get out just isn't logical - there is no one way
valves in the epoxy :-)

Yes, but my assertion is based on the idea that water will get in, no
matter how you handle things, eventually. Once it wicks into small
cracks and distributes itself within the encapsulation, it has a hard
time finding it's way out again, as it doesn't have GPS either

You may have had a great experience, of course you are a superior boat
builder with a golden hammer too, but most encapsulation jobs are not
100%, and like I said, once water gets in, it has a hard time finding
it's way out and can cause a lot of problems. I still say, let the wood
breath in and out, it's gonna' breath in anyway, so why not...

Scotty


You may be right but there have been thousands of plywood boats built
that were sheathed, to the best of my knowledge all of the strip
planked boats, of any size, are sheathed, a tremendous number of boats
use plywood cores in decks. All of these are coated with epoxy.
Epoxy is recommended by every paint company for sealing fiberglass
hulls after doing an osmoses treatment and grinding off the gelcoat.

This is not to say that water never, never, never, will get in but I
suggest that the boats that are epoxy coated last better and are
stronger then uncoated boats.

Whether, or not I am a "superior boat builder with a golden hammer" is
probably debatable but the recommendations I have given are all ones
that I have successfully used.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)


There is a hell of a lot of difference between sheathing or laminating
around plywood, and using a couple of coats of thinned epoxy as primer.

Scotty



Now what? Are you going to tell me that an epoxy-glass composite is
waterproof? After alleging that the epoxy isn't waterproof? If so,
what makes it waterproof? The glass cloth?

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)