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Default 2 part varnish vs. 1 part

Sorry about posting in two places but I am looking for some help on
this. Also I appoligize for the lack of political commentary in this
post but......

I am building an outrigger sailing canoe in cedar strip with a
fiberglass epoxy covering and am having issues with varnish
selection. I have used 1 part on other projects in the past but am
interested in teh possibilities of 2 part. It is aparantly harder,
chemically resistant, and lasts much longer. The problem is that it
is much more expensive. Is it really worth the cost, and is there
anything i can buy that is not as expensive but basically the same.
Many times buying from a boat supply is more expensive just because
is
says 'for boats' on the label. I would really like to try this to
keep the hull well protected but I don't want to spend $60 per quart.

Thanks for the advice,


Bill

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Default 2 part varnish vs. 1 part


"Bill" wrote in message
ups.com...
Sorry about posting in two places but I am looking for some help on
this. Also I appoligize for the lack of political commentary in this
post but......

I am building an outrigger sailing canoe in cedar strip with a
fiberglass epoxy covering and am having issues with varnish
selection. I have used 1 part on other projects in the past but am
interested in teh possibilities of 2 part. It is aparantly harder,
chemically resistant, and lasts much longer. The problem is that it
is much more expensive. Is it really worth the cost, and is there
anything i can buy that is not as expensive but basically the same.
Many times buying from a boat supply is more expensive just because
is
says 'for boats' on the label. I would really like to try this to
keep the hull well protected but I don't want to spend $60 per quart.

Thanks for the advice,


There are actually three general classifications of varnish, Bill. The
traditional "spar varnish" is known as 'long oil varnish'. In most
formulations it is tough, relatively UV-resistant, and beautiful. The
second class is one-part urethane varnish, which looks a lot like long oil
varnish but is a bit tougher and about as UV-resistant. And the third is
two-part linear polyurethane varnish. Poly varnishes, applied properly, are
beautiful and UV-resistant, but difficult to remove.

Any of the three would meet your needs, especially if you have no intention
of leaving your cedar-strip canoe out in the sun indefinitely. Long oil
varnish is easy to "refresh," i.e.--sand and recoat to remove what little
oxidation forms on the surface due to UV. It can be stripped and/or sanded
down to bare wood fairly easily. One-part urethanes are tougher, but
probably not a lot more UV-resistant than long oil varnishes. And they are
very difficult to strip with chemical strippers or a heat gun. They can be
refreshed, but if you allow them to degrade beyond the point where
refreshing is an option, you must remove them to bare wood, and that can be
a very tough job. Two-part linear polyurethane varnish is very hard, holds
its shine exceptionally well, but is fussier to apply with
professional-looking results. Further it cannot be refreshed. When it
looks bad, it must be removed to bare wood, and that will require sanding.
No strippers that I know of will touch the stuff.

My personal preference is long-oil varnish, primarily because it is so
easily applied and refreshed. My standard varnish regimen consists of using
something that isn't really varnish at all, at least in part. Epifanes
makes a product called Gloss Wood Finish, which looks like varnish, behaves
like varnish, but isn't varnish. Starting with bare wood, I use a long-oil
varnish, thinned to about 50%, and allow it to soak in and cure for a few
days before sanding. Then I sand and build the finish with Epifanes Gloss
Wood Finish for about three or four coats. And here's the good part:
Epifanes GWF builds at the rate of one coat GWF to roughly 3 coats of
varnish. So three coats of GWF will give you the same finish thickness as 7
to 9 coats of varnish. AND--and it's a big "and"--you don't have to sand
between coats of GWF if you recoat within 72 hours. AND it's completely
compatible with long-oil varnish. You can alternate layers of GWF and
varnish if you want with great results. After three coats of GWF, I sand
thoroughly, apply another coat of GWF, wait 24 hours, sand lightly, and
apply two or three coats of long-oil varnish, with sanding in between each
coat. The result looks like amber glass on the surface.

Two-part poly varnishes will give great results, but be sure you won't need
to refinish any time soon. The cost is high and the prospect of removing
the poly varnish is something that would keep me from sleeping well.

Hope that helps.

Max


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Default 2 part varnish vs. 1 part

Thanks,
Does that apply to Fiberglass epoxy over the wood as well? I don't
think I will need to reapply often as it will be covered most of the
time but I do want it to be tough. Epifanes website says that the
Gloss wood finish is for bare woods that are oily like teak. Is this
going to be different when it comes to fiberglass epoxy?Their site
doesn't seem to discuss fiberglass applications much.

Thanks again,
Bill

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Default 2 part varnish vs. 1 part


"Bill" wrote in message
ups.com...
Thanks,
Does that apply to Fiberglass epoxy over the wood as well? I don't
think I will need to reapply often as it will be covered most of the
time but I do want it to be tough. Epifanes website says that the
Gloss wood finish is for bare woods that are oily like teak. Is this
going to be different when it comes to fiberglass epoxy?Their site
doesn't seem to discuss fiberglass applications much.

Thanks again,
Bill


I've used Epifanes gloss varnish (long oil) over fiberglass with good
success, so I'm assuming the GWF will work well over glass as well. You
might want to put a coat of varnish on the sanded glass first. It will
raise any glass fibers you may have uncovered with sanding. Those can be
sanded off before applying GWF, but I'm confident GWF is fine on fiberglass.
As an aside, be sure to wipe down any fresh glass with acetone prior to
sanding. That removes the blush and insures that overcoats will adhere.

A good source of information about glass and what to put over it can be
found in the publications from the West System people. Many of their
publications are free.

Max


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Default 2 part varnish vs. 1 part

As an aside, be sure to wipe down any fresh glass with acetone prior to
sanding. That removes the blush and insures that overcoats will adhere.

A good source of information about glass and what to put over it can be
found in the publications from the West System people. Many of their
publications are free.

Max


Thanks I'll be sure to do that. The resin I'm using is low blushing
but you can never be too safe in these things.



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Default 2 part varnish vs. 1 part

"Bill" wrote
Sorry about posting in two places but I am looking for some help on
this. Also I appoligize for the lack of political commentary in this
post but......



That's OK. You can make it up to the group later.

I am building an outrigger sailing canoe in cedar strip with a
fiberglass epoxy covering and am having issues with varnish
selection. I have used 1 part on other projects in the past but am
interested in teh possibilities of 2 part. It is aparantly harder,
chemically resistant, and lasts much longer. The problem is that it
is much more expensive.


That's not the only problem with it.

...... Is it really worth the cost


For your application, not even. I'm guessing what you want is a clear
finish over the final epoxy that will protect it from scuffs & UV.

Maxprop" wrote:
..... Poly varnishes, applied properly, are
beautiful and UV-resistant, but difficult to remove.


What he said.


Any of the three would meet your needs, especially if you have no intention
of leaving your cedar-strip canoe out in the sun indefinitely. Long oil
varnish is easy to "refresh," i.e.--sand and recoat to remove what little
oxidation forms on the surface due to UV. It can be stripped and/or sanded
down to bare wood fairly easily.


As I understand it, he's not going to have bare wood in any event.



One-part urethanes are tougher, but
probably not a lot more UV-resistant than long oil varnishes. And they are
very difficult to strip with chemical strippers or a heat gun. They can be
refreshed, but if you allow them to degrade beyond the point where
refreshing is an option, you must remove them to bare wood, and that can be
a very tough job.


Nah, a heat gun & scraper will take the stuff off, but it's a royal
PITA and everything else Max says is true in spades. Polyurethane is
for furniture, preferably furniture that doesn't get a lot of use. In
my experience it looks great for about a week but it is subject to
crazing & fogging and it cannot be touched up at all.... you gotta
take it all off and put it all back on.

Furthermore (and this is the real kicker) many polyurethane finishes
will not harden properly when laid on over epoxy. I've had this
problem before and it's very frustrating. Manufacturers act like
they've never heard it before but they've known for years. If any
urethane or poly paint/varnish doesn't specifically say that it is
compatible with epoxy primers & undercoats, DON'T put it on over
epoxy!

What you may consider is to do the last laminating over your wood with
a peel ply, then lay on another coat of epoxy with UV inhibitor. MAS &
West both make them and they are both beautiful & tough finishes. They
can be touched up at will. Should be just fine with nothing over it,
unless you're going to leave the boat lay in the sun all season. Then
you might want to put some cheap varnish over it.... it will look
yellow, but the varnish will come off before the epoxy, like a
sacrificial layer
..
Another option, one that I have used in the past and will again this
season, is some type of inexpensive exterior latex like Weatherbeater.
It ain't varnish, but it protects & seals beautifully.

Fresh Breezes- Doug King

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Default 2 part varnish vs. 1 part

That's OK. You can make it up to the group later.

Um......Voting is stupid and we should just bomb the rest of the world
into dust so that we can build cheap condos and more marinas for our
boats.

As I understand it, he's not going to have bare wood in any event.


True but that's been adressed already.

Nah, a heat gun & scraper will take the stuff off, but it's a royal
PITA and everything else Max says is true in spades. Polyurethane is
for furniture, preferably furniture that doesn't get a lot of use. In
my experience it looks great for about a week but it is subject to
crazing & fogging and it cannot be touched up at all.... you gotta
take it all off and put it all back on.


I think i am leaning towards the Epifanes option here. I need it
hard. I'll try not o drag it on the beach but sometimes it happens,
not to mention the trailer.

Furthermore (and this is the real kicker) many polyurethane finishes
will not harden properly when laid on over epoxy. I've had this
problem before and it's very frustrating. Manufacturers act like
they've never heard it before but they've known for years. If any
urethane or poly paint/varnish doesn't specifically say that it is
compatible with epoxy primers & undercoats, DON'T put it on over
epoxy!


Will do.

What you may consider is to do the last laminating over your wood with
a peel ply, then lay on another coat of epoxy with UV inhibitor. MAS &
West both make them and they are both beautiful & tough finishes. They
can be touched up at will. Should be just fine with nothing over it,
unless you're going to leave the boat lay in the sun all season. Then
you might want to put some cheap varnish over it.... it will look
yellow, but the varnish will come off before the epoxy, like a
sacrificial layer


This is a maybe but i really want that glassy look on the boat. I
don't know if i can get that with a peel ply with cheap varnish over
the top.

Thanks,
Bill

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Default 2 part varnish vs. 1 part

"Bill" wrote:
Um......Voting is stupid and we should just bomb the rest of the world
into dust so that we can build cheap condos and more marinas for our
boats.


What kind of bombs should we use? I would favor nukes, they are very
cost effective and we need to reduce current inventory anyway. Might
create a long term liability for the condo/marina developers though.
OK now that we've got the mandatory OT political content out of the
way, let's talk boats!

PS w


I think i am leaning towards the Epifanes option here. I need it
hard. I'll try not o drag it on the beach but sometimes it happens,
not to mention the trailer.


Epifanes and Bristol are both good finishes. You want it hard to
resist scratching but it also has to be flexible and have excellent
adherence as the wood swells & shrinks (this is where epoxy resin has
it all over polyester for laminating stuff to wood). Any of the high-
end varnishes with UV protection and high-build formulation will do
the trick, none of them are inexpensive though. Not in the $60/qt
range, but still pricey. And since you're specifically buying it for
the UV protection, cheap varnish isn't going to do the job.



What you may consider is to do the last laminating over your wood with
a peel ply, then lay on another coat of epoxy with UV inhibitor.



This is a maybe but i really want that glassy look on the boat. I
don't know if i can get that with a peel ply with cheap varnish over
the top.


Peel ply is GREAT stuff. I used it for the first time last year on a
fairly technical prject... now I use it for almost any epoxying/
fiberglassing job; it is not expensive and it saves a lot of work. The
peel ply is a layer of porous cloth that the resin won't stick to.
Sounds great huh? You lay it over the wet lamination, roller it down,
and the resin oozes up thru the peel ply. Sounds better & better eh?
Well it improves adherence, eliminates voids & bubbles, gives you a
higher fiber/resin ratio, and (here's the best part) when you peel it
off the cured lamination, it leaves behind a roughened but uniform
surface that doesn't need any sanding before putting on another layer.
Stronger better faster, and no sanding dust. Secondary bonds put on a
peel ply-ed surface are about 20 to 30% stronger, and if you do it
while the resin is still a little green, it's not a secondary bond at
all.

I have laid on paint over a peel ply-ed surface and came out
beautiful. A resin finish would surely do the same, you could sand &
varnish the final coat if you chose.

Any pictures of your outrigger?

Fresh Breezes- Doug King

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Default 2 part varnish vs. 1 part


wrote in message
oups.com...
"Bill" wrote:
Um......Voting is stupid and we should just bomb the rest of the world
into dust so that we can build cheap condos and more marinas for our
boats.


What kind of bombs should we use? I would favor nukes, they are very
cost effective and we need to reduce current inventory anyway. Might
create a long term liability for the condo/marina developers though.


Indeed. With half-lives in the thousands of years, I think daisy-cutters
and thermite bombs might be more appropriate. And cheaper. Of course that
does nothing to reduce the stockpile of nukes. Perhaps we could send those
to the sun. Perhaps a simultaneous detonation of all the Earth's nukes
might brighten the sun to the point that Chicago would become a "tropical"
paradise, replete with palms growing on the shores of Lake Michigan.

Max


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Default 2 part varnish vs. 1 part

Peel ply is GREAT stuff. I used it for the first time last year on a
fairly technical prject... now I use it for almost any epoxying/
fiberglassing job; it is not expensive and it saves a lot of work. The
peel ply is a layer of porous cloth that the resin won't stick to.
Sounds great huh? You lay it over the wet lamination, roller it down,
and the resin oozes up thru the peel ply. Sounds better & better eh?
Well it improves adherence, eliminates voids & bubbles, gives you a
higher fiber/resin ratio, and (here's the best part) when you peel it
off the cured lamination, it leaves behind a roughened but uniform
surface that doesn't need any sanding before putting on another layer.
Stronger better faster, and no sanding dust. Secondary bonds put on a
peel ply-ed surface are about 20 to 30% stronger, and if you do it
while the resin is still a little green, it's not a secondary bond at
all.


That actually sounds like a great solution to my vaccuum bagging
dillema. The designer doesn't say anything about bagging but it
helps. The problem is I have never done fiberglass before and I
didn't want to spend another $300+ on equipment but what you are
talking about seems to be like half the way to VB without using pumps
and stuff. I will definately do that. I am looking for ways to
reduce weight without reducing strength and think this will help.

I have laid on paint over a peel ply-ed surface and came out
beautiful. A resin finish would surely do the same, you could sand &
varnish the final coat if you chose.


Yeah there will be a lot of sanding involved if I want that thick
glass look.

Any pictures of your outrigger?


Well the structural building hasn't started yet, I'm in the planning,
buying, and tooling up stages right now. It probably wont rain much
here in So Cal this year anymore so i can get the wood pretty soon and
get something more substantial done but I don't want to rush. This is
the design http://homepages.paradise.net.nz/garyd/plans.html but I am
making a few minor changes, all designer approved of course. i am
using a second outrigger that will be set on the open side, like the
BW pic at the bottom of the page, but in close to the hull for safety
and weight reduction, making it really hard to flip. I am adding a
couple extra hiking seats to improve balance and I am going with a
slightly larger sail. Also I am using bamboo for the crossbeams and
if i can find it for the mast. There will be a forestay and the mast
will sit in a reinforced tube indtead of being just strapped to the
beam. Later I am going to try to add a small jib sail, mostly to
practice using one. The jib may not really add any speed but I want
to find out for myself. I am also considering doing a traditional
carving at the bow and stern. The designer has a lot of experience in
polynesia and he says that traditionally they would often add a
carving of a bird head and tail. I am thinking an Albotross for
luck. For a name I am thinking 'Moli' which is the Hawaiian name for
the Laysan Albotross. The only problem is that I have never done
carvings before so that will be a dependent on the outcome. I am going
to have to buy the paddles because I don't think I get the curve right
but I am going to attempt to make the steering oar. There are
instructions with my plans and I want to get it long enough.

I am trying to come up with some sort of rest for the oar that will
allow it to hold its position, kind of like an autopilot, so I don't
have to hold it all the time. I think a simple box with round notches
cut out to let it rest in certain positions with some kind of a latch
to hold it in place.

I have a lot of work ahead of me.

Bill



 
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