On Jul 11, 5:54 pm, Lodewijk Stegman
wrote:
schreef oups.com

On Jul 11, 5:08 pm, Lodewijk Stegman
wrote:
There's not all that much content in your post.

Maybe you should point out your experiences and your engineering.
I meant what I said when I stated that it's almost impossible to use
wood and epoxy together if you don't rely on it's waterproof
qualities.

Why so narrow minded. I use epoxy as an anhesive and sometimes as a
laminating resin, I use paint to protect wood.

Narrow-minded? I have some experience with epoxy too, and I wonder what
makes you so self assured about epoxy not being waterproof.

I am a boat builder, wooden boats at that. And please read Pauls post
above, please.

As far as
'goo's' go, you will have a hard time finding one more waterproof than
epoxy.

And to suggest I said anything different would be innacurate at best.
Although there are many out there I have not used, so I won't guess

Of course everything relative. Glass or steel will be more waterproof
than epoxy, but it is waterproof enough to use it in woodcore boats or
stitch-and-glue boats to make them last for a very long time.

Waterproof "enough". Now you are starting to understand. But maybe not
for the guy who wants to use it to seal a bamboo mast, where is where
this discussion started.


For instance: wood shrinks and swells with changing humidity. Epoxy
won't move with it. How do you engineer that?

Epoxy moves just fine in joints.

It might work with massive wood joints, if the cross-sections are
relatively small.

Not going to take on this one, I don't have the time or inclination.
But trust me, there is much more to that story.

I works better when glueing plywood. The joints last
longest in boats that are designed to be build using epoxy throughout.

Or allow for escape of aquired (not built on wet wood) moisture and
finish with something like paint. And if I am understanding your
assumptions, encapsulated boats should last forever, and they don't.

Do you build such boats?

I do, professionally, have for decades.


In fact it is much more pliable than
polyester,

Cured epoxy can vary in flexibility, depending on the type of hardener
you use. Not every combination works, if you want flexibility.

So you are telling me to use the right mixes for the job. ok I will

Comparing epoxy and polyester when talking about gluing is useless.
Polyester resin sucks as a glue for wood.

I never said anything like that. I said " I use epoxy as an anhesive
and sometimes as a laminating resin, I use paint to protect wood". Are
you my new troll? Rehtorical question, don't bother.


please leave me alone now. I am not here to teach you about
boats.

Maybe I'm here to teach you about epoxy...

Well if elaborating on my posts and making up assertions you wish I
made is teaching, consider me a disgrunteled student.

--
Lodewijk

Apologies to those who suffered through this all.
JW

On 11 Jul 2007 21:08:43 GMT, Lodewijk Stegman
wrote:

schreef in
oups.com

On Jul 11, 4:21 pm, Lodewijk Stegman
wrote:

I'm sorry to say, but you ARE wrong. It is almost impossible to use
epoxy and wood together without depending on the waterproof qualities
of epoxy. I wonder what you have used it for and how you engineer
your work if you're so sure it leaks.

Have a great day and go build a boat!

Sure. You go build a heavy wooden boat. But don't use epoxy. You're
not knowledgeable enough.

You don't know what you don't know. You certainly know nothing about
me and my experience. Next time however it would help if your read my
post and Pauls (epoxy expert, retailer) post for content, instead of
just trying to feed your ego with ignorant insults. Later kid...

There's not all that much content in your post.

Maybe you should point out your experiences and your engineering.
I meant what I said when I stated that it's almost impossible to use wood
and epoxy together if you don't rely on it's waterproof qualities.

For instance: wood shrinks and swells with changing humidity. Epoxy won't
move with it. How do you engineer that?

Well, I have seen a large number of boats built of wood and epoxy -
strip planked, cold molded and duracore composite all come to mind.
These boats are all made of wood and epoxy and seem to have no
problems with dimensional changes due to moisture content.





Bruce in Bangkok
(brucepaigeatgmaildotcom)

--
Posted via a free Usenet account from http://www.teranews.com

Boy this thread is getting a bit nasty. Calm down guys!

One more point I want to make that might help cool things down a bit.....

wood expands and contracts with moisture

things like epoxy, fiberglass, paint, and just about all other things,
expand and contract with temperature.
So - wood and the epoxy on it don't expand and contract together...
This can cause some of the issues brought up here. Always best to
complete seal the wood with epoxy, not just one side. Also, plywood,
because of the way it is made etc. expands and contracts very little (at
least compared to 'regular' wood).


Also epoxies stick really well to most materials and is often considered
sort of a universal primer.

polyester resin (fiberglass resin) doesn't bond well (or long) to
anything but itself (I and my customers report polyester resin to wood
bond failures after a few years maybe 10 years at best). This is why
fiberglass boats are generally 100% fiberglass and not half fiberglass
and half wood (as might/could be the case with epoxy resin). So.... you
can repair fiberglass with epoxy but fixing epoxy with fiberglass resin
in not recommend (but many folks do and they get away with it).

Epoxy resins just have all around better physical properties than
polyester resin, but usually cost more.

I vaguely recall seeing water absorption numbers for epoxy at something
like 1/10 of a percent. Don't ask me where or how I got that number,
just something that is floating adrift in my head.


cheers everyone

paul oman
progressive epoxy polymers






Lodewijk Stegman wrote:

schreef in
oups.com



On Jul 11, 4:21 pm, Lodewijk Stegman
wrote:





I'm sorry to say, but you ARE wrong. It is almost impossible to use
epoxy and wood together without depending on the waterproof qualities
of epoxy. I wonder what you have used it for and how you engineer
your work if you're so sure it leaks.



Have a great day and go build a boat!


Sure. You go build a heavy wooden boat. But don't use epoxy. You're
not knowledgeable enough.





You don't know what you don't know. You certainly know nothing about
me and my experience. Next time however it would help if your read my
post and Pauls (epoxy expert, retailer) post for content, instead of
just trying to feed your ego with ignorant insults. Later kid...



There's not all that much content in your post.

Maybe you should point out your experiences and your engineering.
I meant what I said when I stated that it's almost impossible to use wood
and epoxy together if you don't rely on it's waterproof qualities.

For instance: wood shrinks and swells with changing humidity. Epoxy won't
move with it. How do you engineer that?

On Thu, 12 Jul 2007 03:13:56 GMT, Paul Oman
wrote:


Boy this thread is getting a bit nasty. Calm down guys!

One more point I want to make that might help cool things down a bit.....

wood expands and contracts with moisture

things like epoxy, fiberglass, paint, and just about all other things,
expand and contract with temperature.
So - wood and the epoxy on it don't expand and contract together...
This can cause some of the issues brought up here. Always best to
complete seal the wood with epoxy, not just one side. Also, plywood,
because of the way it is made etc. expands and contracts very little (at
least compared to 'regular' wood).


Also epoxies stick really well to most materials and is often considered
sort of a universal primer.

polyester resin (fiberglass resin) doesn't bond well (or long) to
anything but itself (I and my customers report polyester resin to wood
bond failures after a few years maybe 10 years at best). This is why
fiberglass boats are generally 100% fiberglass and not half fiberglass
and half wood (as might/could be the case with epoxy resin). So.... you
can repair fiberglass with epoxy but fixing epoxy with fiberglass resin
in not recommend (but many folks do and they get away with it).

Epoxy resins just have all around better physical properties than
polyester resin, but usually cost more.

I vaguely recall seeing water absorption numbers for epoxy at something
like 1/10 of a percent. Don't ask me where or how I got that number,
just something that is floating adrift in my head.


cheers everyone

paul oman
progressive epoxy polymers


Ha! Maybe a chance to get me some free information here =;-}

If you were planning on building a composite potable water tank what
would you use to line/paint the inside?

I have had several boats that had integral tanks. In one case the tank
appeared to have been painted inside with polyester resin and a second
boat that appeared to have gel coat on the inside.

I am considering building a spare water tank out of plywood, lined and
taped with glass, and do not have a big selection of epoxy available
here. My thoughts were to go ahead and paint it inside with several
coats of epoxy, let it cure for several weeks and then flush it with
several/many changes of water.

If some form of special, "This stuff is for lining water tanks" resin
was available I'd use it but as far as I can discover there is
nothing like that available in the country.

Thanks for any information you can give me.





Bruce in Bangkok
(brucepaigeatgmaildotcom)

--
Posted via a free Usenet account from http://www.teranews.com

Ha! Maybe a chance to get me some free information here =;-}

If you were planning on building a composite potable water tank what
would you use to line/paint the inside?

I have had several boats that had integral tanks. In one case the tank
appeared to have been painted inside with polyester resin and a second
boat that appeared to have gel coat on the inside.

I am considering building a spare water tank out of plywood, lined and
taped with glass, and do not have a big selection of epoxy available
here. My thoughts were to go ahead and paint it inside with several
coats of epoxy, let it cure for several weeks and then flush it with
several/many changes of water.

If some form of special, "This stuff is for lining water tanks" resin
was available I'd use it but as far as I can discover there is
nothing like that available in the country.

Thanks for any information you can give me.





Bruce in Bangkok
(brucepaigeatgmaildotcom)



---------------

gel coat is just thickened polyester resin.

epoxies tested and approved for potable water (NSF 61 approvals) are
generally (always????) test /approved for tanks over 1000 gallons or
pipelines over 16 inches dia. Some folks don't worry about it, others
do......

paul
- progressive epoxy polymers

On Thu, 12 Jul 2007 12:19:56 GMT, Paul Oman
wrote:


Ha! Maybe a chance to get me some free information here =;-}

If you were planning on building a composite potable water tank what
would you use to line/paint the inside?

I have had several boats that had integral tanks. In one case the tank
appeared to have been painted inside with polyester resin and a second
boat that appeared to have gel coat on the inside.

I am considering building a spare water tank out of plywood, lined and
taped with glass, and do not have a big selection of epoxy available
here. My thoughts were to go ahead and paint it inside with several
coats of epoxy, let it cure for several weeks and then flush it with
several/many changes of water.

If some form of special, "This stuff is for lining water tanks" resin
was available I'd use it but as far as I can discover there is
nothing like that available in the country.

Thanks for any information you can give me.





Bruce in Bangkok
(brucepaigeatgmaildotcom)



---------------

gel coat is just thickened polyester resin.

epoxies tested and approved for potable water (NSF 61 approvals) are
generally (always????) test /approved for tanks over 1000 gallons or
pipelines over 16 inches dia. Some folks don't worry about it, others
do......

paul
- progressive epoxy polymers

Thanks, I understand.


Bruce in Bangkok
(brucepaigeatgmaildotcom)

--
Posted via a free Usenet account from http://www.teranews.com

On Jul 11, 11:13 pm, Paul Oman wrote:
Boy this thread is getting a bit nasty. Calm down guys!

One more point I want to make that might help cool things down a bit.....

Sorry, I am a nasty guy and I don't like being slandered by some punk
kid.

I vaguely recall seeing water absorption numbers for epoxy at something
like 1/10 of a percent. Don't ask me where or how I got that number,
just something that is floating adrift in my head.

And that was my simple point. Even in a lab epoxy is not "waterproof",
I know it sounds picky with the numbers you stated, but who uses epoxy
in lab conditions anyway. And certainly in the use the Origional
Poster has in mind it won't be water proof, in fact it may prove
detremental by holding aquired moisture (through cracks and osmosis)
in. Even if he went to the expence of using the water tank rated stuff
you base your numbers on, and certainly not if he uses off the shelf
maring epoxy...


cheers everyone

Cheers to you too, but the guy owes me an apology.


paul oman
progressive epoxy polymers

On Jul 12, 10:33 am, wrote:


Cheers to you too, but the guy owes me an apology.

Better yet, just let it die, my feelings will heal

schreef in
oups.com

On Jul 11, 5:54 pm, Lodewijk Stegman
wrote:

As far as
'goo's' go, you will have a hard time finding one more waterproof
than epoxy.

And to suggest I said anything different would be innacurate at best.
Although there are many out there I have not used, so I won't guess

If I remember correctly you were discussing a use of epoxy and glassfiber
which, save the use of bamboo, was a perfectly normal method to
strengthen and weatherproof a wooden construction.
It was silly to state that epoxy is not waterproof in such a context.
It's waterproof enough.

Of course everything relative. Glass or steel will be more waterproof
than epoxy, but it is waterproof enough to use it in woodcore boats
or stitch-and-glue boats to make them last for a very long time.

Waterproof "enough". Now you are starting to understand. But maybe not
for the guy who wants to use it to seal a bamboo mast, where is where
this discussion started.

Your remark did not specifically relate to the fact that the epoxy was
used on bamboo. You simply said: iet's not waterfroof.
Thousands of boats have been built using epoxy to prove that epoxy is
watertight enough for use on dimensionally stable wood. If the wood had
the right moisture content at the start, the boats won't rot from within,
so why keep stressing that epoxy is not completely, absolutely
waterproof?
Fact is that as long as the epoxy or epoxy-and-glass skin is not
punctured, those boats have an almost infinite life-span. Water-
absorption through an intact epoxy-skin is not a factor.

[epoxy used only for gluing]

It might work with massive wood joints, if the cross-sections are
relatively small.

I works better when glueing plywood. The joints last
longest in boats that are designed to be build using epoxy
throughout.

Or allow for escape of aquired (not built on wet wood) moisture and
finish with something like paint.

Aquired moisture is a factor in the restoration of boats. New boats
should be built of wood with the right moisture content.

And if I am understanding your
assumptions, encapsulated boats should last forever, and they don't.

Encapsulating traditionally built (skin-on-frame) boats is a tricky
business.
Boats that were designed to be built using epoxy can be encapsulated in a
reliable way without any difficulty and can last very long. At least as
long as any polyester boat en with some care as long as any boat.

Comparing epoxy and polyester when talking about gluing is useless.
Polyester resin sucks as a glue for wood.

I never said anything like that. I said " I use epoxy as an anhesive
and sometimes as a laminating resin, I use paint to protect wood".

You at least created the impressing of making that comparison, because
your remark on polyester directly followed your remark on epoxy being
pretty pliable.

--
Lodewijk

Bruce schreef in


On 11 Jul 2007 21:08:43 GMT, Lodewijk Stegman
wrote:

For instance: wood shrinks and swells with changing humidity. Epoxy
won't move with it. How do you engineer that?

Well, I have seen a large number of boats built of wood and epoxy -
strip planked, cold molded and duracore composite all come to mind.
These boats are all made of wood and epoxy and seem to have no
problems with dimensional changes due to moisture content.

You don't have to convince me.

I have seen those boats too. And you and I know why these boats have no
problems with dimensional changes due to moisture content.
The moisture content does not change (enough) to crate problems, once the
wood is sealed from external moisture.
Which seems to prove that epoxy is waterproof enough for this purpose.

Practically spoken, epoxy is waterproof.

--
Lodewijk