On Sun, 12 Dec 2004 00:47:37 +0000, Paul Oman wrote:

Solvent thin the first coat or two of epoxy for better penetration and bonding -
especially along edges, etc. Just about any solvent will work. Thin 15 - 25 % or so.
A little bit of solvent will greatly lower the viscosity.

My advice to anyone attempting this is to measure the quantity of diluent
carefully, and test the resulting mixture before using it to coat anything
important. Sometimes adding solvent to epoxy will cause it not to cure
properly, and of course, the physical properties will be affected.

--Mac

Mac wrote:
On Fri, 10 Dec 2004 12:23:19 -0600, Donnie Gilliland wrote:
I would not cover wood with epoxy without putting something on top of the
epoxy, because epoxy clouds slowly over time. You could, perhaps, use two
coats of epoxy with a varnish on top of that. Be sure to do a test panel
to make sure that the varnish will cure properly over the epoxy.

True, one WILL need to cover even UV-resistant epoxy with varnish/paint
for UV protection. Besides, the glossy surface is what keeps most the UV
out - and as much of the UV that slips through the varnish, needs to be
reflected from the invisible border between epoxy and varnish, which
also is the (one more) reason why first sanding shouldn't be more coarse
than necessary.

I, like most people, had to listen for advices. After consulting
Epifanes, Hempel and others, this is what I boiled it down to.:
http://menzi.dk/html/varnish.html

And how it turned out:
http://menzi.dk/gfx/maxi/irene_storm.jpg

I got a very informative transcript (in Danish) from Georgia McDonald,
Woodenboats - I suppose it exists in English as well.

One Ocean Kayaks got a test panel, with NO varnish I believe.



My correspondance with a vendor:

Date: 2004-06-01 14:46:42 -0400 (Tue)
From: "Doug Theobalds"
Reply-to:
To: "steen"
Subject: PU varnish on epoxy ?
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Any of the two-part Polyurethanes will offer the best in adhesion and
hardness over epoxy. Ensure that the Amine blush has been removed from
the epoxy. As long as the surface is clean, dry , and sanded, apply full
strength.

Doug Theobalds
70 Water Street
Thomaston, ME 04861
207.354.0804
fax. 207.354.0387
* Epifanes North America Inc.
* Gebo North America Inc.
* Mastervolt USA Inc.
* Rowable Classics
* Stazo Marine Equip. NA Inc.
* Van de Stadt Timber Inc.


-----Original Message-----
From: steen ]
Sent: Sunday, May 30, 2004 4:11 PM
To:
Subject: PU varnish on epoxy ?



Hello,

What is your recommandated procedure regarding PU varnishing on
epoxy..?? As painting on epoxy??

It's for a stripbuilt kayak.

Cheers
--
steen - menzi.dk
Ready for OpenOffice?
---



Date: 2004-06-02 09:02:10 -0400 (Wed)
From: "Doug Theobalds"
Reply-to:
To: "steen"
Subject: PU varnish on epoxy ?
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Any of the two-part Polyurethanes will offer the best in adhesion and
hardness over epoxy. Ensure that the Amine blush has been removed from

the epoxy. As long as the surface is clean, dry , and sanded, apply
full strength.

Cheers - but I'll be a bit more specific then:

What grit to use for sanding before first layer varnish..??

220 grit wet or dry

How many layers in total..??

Two if paint. 4 if varnish.

What grit to use before last layer..?? (don't plan on sanding between
layers)

320 grit wet or dry is sufficient prior to final coat.

Thanks again, and sorry for not being more specific in my first letter.
--
steen - menzi.dk
Ready for OpenOffice?
---





Sometimes a blow-dryer
or hot air gun can help the epoxy flow, and help get rid of tiny bubbles.

I'll try to keep this in mind!! Cheers!!

Hygge
--
steen - menzi.dk
I have a beam of light to catch.
---

On Sun, 12 Dec 2004 00:47:37 +0000, Paul Oman wrote:

Solvent thin the first coat or two of epoxy for better penetration and bonding -
especially along edges, etc. Just about any solvent will work. Thin 15 - 25 % or so.
A little bit of solvent will greatly lower the viscosity.

Hmmm, to me the idea of adding solvent to epoxy doesn't sound too
good. The basic idea behind encapsulating wood in solvent free
epoxy rather than just varnish is to get a vapour-tight seal
around the wood. (Yes I know it won't be strictly vapour-tight but
it is orders of magnitude better than any varnish). Adding a solvent
may make the epoxy porous.

If you really want lower viscosity you could either buy an epoxy
that has low viscosity all by itself or you can heat it up to say
30C or so. If you for heating the epoxy you should choose a
type that has a long pot life or work with small batches.

A somewhat risky but simple alternative is to 'heat-gun' the surfaces
right after applying epoxy. Don't overdo it. There should be no smell
or fumes!

--
================================================== ==================
Martin Schöön * * * * * * * * * *"Problems worthy of attack
* * * * * * * * * * * * * * * * * prove their worth by hitting back"
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *Piet Hein
================================================== ==================

I beleive System Three says you can dilute their epoxy by 5% by volume
for better penetration of the BASE coat of epoxy to seal the wood grain.
The amount you can dilute may vary by brand.

You then proceed with other coats of epoxy for lamination undiluted. I
tried this once before with using the resin as a cheap rot-fix for a
rotting window frame. It worked pretty good but took longer to cure.

What worked the best was a combination of diluting the resin, heating
the wood to be treated, and warming the epoxy. Heating the wood works
the best but is not always easy.

--
Matt
JEM Watercraft
http://www.jemwatercraft.com/


Martin Schöön wrote:
On Sun, 12 Dec 2004 00:47:37 +0000, Paul Oman wrote:


Solvent thin the first coat or two of epoxy for better penetration and bonding -
especially along edges, etc. Just about any solvent will work. Thin 15 - 25 % or so.
A little bit of solvent will greatly lower the viscosity.


Hmmm, to me the idea of adding solvent to epoxy doesn't sound too
good. The basic idea behind encapsulating wood in solvent free
epoxy rather than just varnish is to get a vapour-tight seal
around the wood. (Yes I know it won't be strictly vapour-tight but
it is orders of magnitude better than any varnish). Adding a solvent
may make the epoxy porous.

If you really want lower viscosity you could either buy an epoxy
that has low viscosity all by itself or you can heat it up to say
30C or so. If you for heating the epoxy you should choose a
type that has a long pot life or work with small batches.

A somewhat risky but simple alternative is to 'heat-gun' the surfaces
right after applying epoxy. Don't overdo it. There should be no smell
or fumes!

On Sun, 12 Dec 2004 16:53:20 +0000, William R. Watt wrote:

The problem on the interior is to *increase* the viscosity of the resin so
it will not run down the sides, not to make it more runny.

I keep hearing and reading about this but I have never had this
problem myself and I started to use epoxy back in 1979. I guess it
must depend largely on the type/brand you use.

(If you visit the Building section of http://hem.bredband.net/b262106/
you will see I have worked some vertical surfaces as well as horizontal
ones)
--
================================================== ==================
Martin Schöön * * * * * * * * * *"Problems worthy of attack
* * * * * * * * * * * * * * * * * prove their worth by hitting back"
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *Piet Hein
================================================== ==================

My correspondence with a vendor:


Date: 2004-06-01 14:46:42 -0400 (Tue)
From: "Doug Theobalds"
Reply-to:
To: "steen"
Subject: PU varnish on epoxy ?
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Any of the two-part Polyurethanes will offer the best in adhesion and
hardness over epoxy. Ensure that the Amine blush has been removed from
the epoxy. As long as the surface is clean, dry , and sanded, apply full
strength.

Doug Theobalds
70 Water Street

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


keep in mind that most clear coats (including pricey 2 part urethanes - awlgrip
(tm) type coatings) - contain almost no UV blockers. I know of only two that do
- auto clear coat being the primary one.
Also aware of a water based clear acrylic that has uv blockers.

These clear UV blocking topcoats usually find their way on to bartops and table
tops...

pigment, in the epoxy or in a topcoat, are considered the primary UV blockers.

paul oman
progressive epoxy polymers
www.epoxyproducts.com/marine.html

Jim:

Solvent thinning the epoxy will weaken it. But a sealing coat is not structural and besides,
you are then topcoating it with unthinned epoxy. Consider the thinned epoxy to be a tie coat
or a penetrating primer - similar to CPES (look at a CPES msds). Thinning the epoxy will
help prevent it from failing/peeling on the edges of the wood where the epoxy begins.

paul oman


Jim Conlin wrote:

I'm not sure whether thinning epoxy is such a good idea until I see lab test data on how
perneable the resultant finish id. It's certainly true that thinned epoxy is measurably
degraded in strength. You can drastically improve the spreadability of epoxy with heat-
a heat lamp or a heat gun.

Paul Oman wrote:

Solvent thin the first coat or two of epoxy for better penetration and bonding -
especially along edges, etc. Just about any solvent will work. Thin 15 - 25 % or so.
A little bit of solvent will greatly lower the viscosity.

you could also use an epoxy paint instead of an raw epoxy resin - would gain color,
less sag, more film thickness, possibly more flex. Priced about the same as the
resin to double the price.

I would even do the thinning thing if using varnish. - picked that tip up from a
custom wooden kayak maker......

regards
paul oman
progressive epoxy polymers
---------

Jim Conlin wrote:

The epoxy will only cloud if it's in the sun. It's difficult to get it to lay
smooth, so for interior areas where a decent finish is wanted, additional finish
is needed. For lockers, bilges, etc. where appearance isn't important and the
sun don't shine, you can stop after a decent cooating has been achieved.
For some interior joinery, i'll sometimes pre-coat sheets of plywood before
cutting parts out. Makes finishing easier.

Mac wrote:

On Fri, 10 Dec 2004 12:23:19 -0600, Donnie Gilliland wrote:

I'm constructing a 10" tunnel hull and am at the point where I need to
seal/finish the interior of the hull before putting the decking on. The
boat is not going to be left out in the elements or used in sal****er but
will be stored indoors when not used.
My question to the group is this, can I use a good grade of spar varnish to
seal the interior or would the epoxy encapsulation be the better choice? (I
plan on using epoxy and fiberglass on the hull exterior).

Any brands of varnish or epoxy to suggest?
Any suggestions?

Thanks in advance
Don

I would not cover wood with epoxy without putting something on top of the
epoxy, because epoxy clouds slowly over time. You could, perhaps, use two
coats of epoxy with a varnish on top of that. Be sure to do a test panel
to make sure that the varnish will cure properly over the epoxy.

I have done this before. It especially works well for flat horizontal
surfaces where you can really build up the epoxy. Sometimes a blow-dryer
or hot air gun can help the epoxy flow, and help get rid of tiny bubbles.

--Mac

--

"Living on Earth is expensive, but it does include
a free trip around the Sun every year."

============================================
PAUL OMAN Progressive Epoxy Polymers, Inc.
Frog Pond Hollow - 48 Wildwood Dr
Pittsfield NH 03263
10-4 Monday-Thur EST 603-435-7199
VISA/MC/Discover/Paypal

http://www.epoxyproducts.com
sign-up for free email newsletter!
============================================




--


"Living on Earth is expensive, but it does include
a free trip around the Sun every year."


============================================
PAUL OMAN Progressive Epoxy Polymers, Inc.
Frog Pond Hollow - 48 Wildwood Dr
Pittsfield NH 03263
10-4 Monday-Thur EST 603-435-7199
VISA/MC/Discover/Paypal

http://www.epoxyproducts.com
sign-up for free email newsletter!
============================================

Paul Oman wrote:

keep in mind that most clear coats (including pricey 2 part urethanes - awlgrip
(tm) type coatings) - contain almost no UV blockers.

Right - you have to make sure what they are selling you.

Regards
--
steen - menzi.dk
I have a beam of light to catch.
---

Hi Don

My personal choice would be 2 part epoxy if you can still get it in your
neck of the woods.... I built a 15 foot tunnel boat that I had a Honda
motorcycle engine in at first with 2 jet drives.... I later converted it to
a 60hp outboard. Lots of elbows in that tunnel. The 2 part epoxy is tough
to beat...

Regards
Steve



"Donnie Gilliland" wrote in message
...
I'm constructing a 10" tunnel hull and am at the point where I need to
seal/finish the interior of the hull before putting the decking on. The
boat is not going to be left out in the elements or used in sal****er but
will be stored indoors when not used.
My question to the group is this, can I use a good grade of spar varnish
to
seal the interior or would the epoxy encapsulation be the better choice?
(I
plan on using epoxy and fiberglass on the hull exterior).

Any brands of varnish or epoxy to suggest?
Any suggestions?

Thanks in advance
Don

I used 3-4 coats of tung oil on a tongue and groove cedar sole that I put in
a friend's daysailer. It held up quite well and should probably be touched
up every two years (Great Lakes area/Canada). Oil is more penetrating and
not much for forming a surface film like a varnish, so the physical abrasion
resistance of a plastic-like varnish will not be demonstrated. I really
don't think abrasive action is very high on the floor since soft-soled shoes
are the norm on such a craft.
The boat (Albacore 16) is kept out of doors on a trailer with a cover over
the whole thing when not used.
That's what I think,
Leo
"Dick Robertson" wrote in message
...
On Fri, 10 Dec 2004 14:37:27 -0500, "ddinc"
wrote:

Be aware that epoxy will deteriorate under sunlight
and needs a UV (exterior varnish or other) coating.

"Donnie Gilliland" wrote in message
...
I'm constructing a 10" tunnel hull and am at the point where I need to
seal/finish the interior of the hull before putting the decking on.
The
boat is not going to be left out in the elements or used in sal****er
but
will be stored indoors when not used.
My question to the group is this, can I use a good grade of spar
varnish
to
seal the interior or would the epoxy encapsulation be the better
choice?
(I
plan on using epoxy and fiberglass on the hull exterior).

Any brands of varnish or epoxy to suggest?
Any suggestions?

Thanks in advance
Don



I've used epoxy with good success. However, in a recent set of plans I
purchased for a small boat, the designer suggested an oil finish
inside the boat because it is much easier to maintain since it is
usually difficult to refinish inside a boat. A good compromise might
be to epoxy encapsulate any hidden or inaccessable areas and use a
marine oil finish on interior exposed areas. In any case, varnish
would be a bad idea because maintenance would be high. West Epoxy has
never let me down.

Dick R.
Wilmington,NC