An old topic, but I am *newly* confused. I installed new doors and
trim, coated with 3 coats of shellac. After just two or three years
the bathroom doors and trim are showing major signs of apparent water
damages, with the finish roughening and lifting, especially around the
upper portions of the doors where the shower steam condenses on the
doors and trim.

Here's the question. Recently I read that shellac is actually MORE
waterproof than varnish, and I have read of at least two double-
planked boats in WoodenBoat magazine that have shellac between the
layers of planking because it is believed to be more waterproof.

So what gives? I need to refinish the doors and trim as soon as the
weather improves enough to open the windows, but varnish or shellac?
Of course, I prefer shellac, as it is less toxic and dries much
faster, but if varnish is the solution, then I need to use that.

Any ideas and explanations?

You will find that shellac is not a good waterproofing agent. Perhaps
what you read about boat guy using it was their use of it as primer.

To be able to say that it has held up well in a hot steamy bathroom is
a good testament to your application.

You can settle this for yourself; put some shellac on a board, then
put some varnish on another area. Put a wet glass on each area and
see which one shows signs of moisture penetration.

Shellac is an excellent choice of wood primer to me. But for a finish
application in a wet environment I wouldn't use it for a finish coat.
I would look at some of the better water (or solvent) based
polyurethanes. There are a lot of them out there. Maybe you can con
Lew into commenting on this subject, as he is a boat guy.

I personally don't like spar varnishes, etc., as they dry too soft for
stationary applications, are not highly abrasion resistant, and since
most are based on old oil formulas they yellow badly. Some of the
newer polyurethanes dry very hard, stay pretty clear, and are easy to
apply with gun, pad, or brush.

Make sure whatever you choose to apply, you sand/clean the surfaces
thoroughly as the wet, soapy steam and condensate can murder your
finish.

As for fear of poisons, this discussion rears its head frequently in
woodturning. The answer is always the same, and that is that almost
all finishes (certainly those we buy without a license!) are food safe
when dried. As a matter of fact, this was just brought up again on
the spinning side of the wood fence:

http://tinyurl.com/2d3a9z

Good luck!

Robert

On Mar 10, 9:05 pm, "
wrote:


Perhaps
what you read about boat guy using it was their use of it as primer.

And that, my friends, is the most confusing sentence I've ever
read....

On Mar 10, 7:19 pm, Jeff wrote:

And that, my friends, is the most confusing sentence I've ever
read....

You should read more of my posts. I can be more confusing that than
that... and have! My brain often works a lot faster than my typing,
so it wanders away while my fingers are still working.

I have I have a tendency to try to answer a question as quickly as
possible if I think I can be of some help. I don't always worry about
punctuation, grammar, correct pronoun references, etc. I leave that
to others here that have the time and patience to turn in a
professional quality dissertation. All I want to do is to disseminate
information, or in some cases, just my own opinion based on my
experience.

But if you were confused (and of course actually interested in the
subject), tell me where I threw you off and I will be glad to
elucidate.

Robert

"Jeff" wrote in message
...
On Mar 10, 9:05 pm, "
wrote:


Perhaps
what you read about boat guy using it was their use of it as primer.

And that, my friends, is the most confusing sentence I've ever
read....




I understood it to mean that what the poster read (past tense) about "the
boat guy" (apparently someone who works with boats) was that the the boat
guy was using shellac as a primer. Therefore, the OP concluded that
shellac was good for use on wood exposed to water (or condensation).
However, Robert suggested that the OP might have been misled because the
"boat guy" was only using shellac as a primer; which is to infer that, after
using shellac as a primer, the "boat guy" used some other coating for water
protection. But, unless the "boat guy" responds, we might never really know
for sure.
Let's see if I'm right.
Robert?

Max

On Mon, 10 Mar 2008 18:05:02 -0700, wrote:

You will find that shellac is not a good waterproofing agent. Perhaps
what you read about boat guy using it was their use of it as primer.


Dewaxed shellac slows down moisture vapor exchange, and thus wood
movement, better than any other finish with the possible exception of
epoxy.


You can settle this for yourself; put some shellac on a board, then
put some varnish on another area. Put a wet glass on each area and
see which one shows signs of moisture penetration.

I put several coats of dewaxed shellac on a piece of jatoba. I then set
glasses of water, both tap temperature and iced on it and left them
overnight. No water marking. Then I just sprinkled it and left large
drops of water on the surface. Still no marking.

It's the WAX that causes the water marks.

That said, I'd use poly on horizontal surfaces in a bathroom just to be
extra cautious.

On Mar 10, 8:17 pm, "Max" wrote:

SNIP

Let's see if I'm right.
Robert?

Dead spot on. Like you were reading my mind.

That's kind of scary.... ;^)

Robert

On Mar 10, 9:14 pm, Larry Blanchard wrote:

Dewaxed shellac slows down moisture vapor exchange, and thus wood
movement, better than any other finish with the possible exception of
epoxy.

I don't know, but I would be willing to learn if you could point me in
the direction of that information. I thought the post catalyzed 2 K
urethanes with flex additives would be better than shellac, especially
for finishing wood products. No?

Got my interest up, there. Love to see some empirical data if it is
easy to get to, or just post a quick link.

I put several coats of dewaxed shellac on a piece of jatoba. I then set
glasses of water, both tap temperature and iced on it and left them
overnight. No water marking. Then I just sprinkled it and left large
drops of water on the surface. Still no marking.

It's the WAX that causes the water marks.

That is absolutely true if you have the right shellac. The clear
blonde, dewaxed stuff that O'Deen used to sell was supposed to be able
to deflect bullets after being mixed nd properly applied. As hard as
a good poly, and almost as water proof. But you had to roll your own
when using it as this was not over the counter stuff.

Reading between the lines you can easily see that it is that blend the
OP was talking about as it is put between the planks on a double
planked deck. This is because shellac (no matter what amount of
additives are) is not very UV resistant. If he had used the super
blond dewaxed brewed mix on his doors he probably wouldn't be having
any problems now.

I made an assumption (perhaps incorrectly) that the OP used off the
shelf shellac which is probably a Zinsser (or similar) product, and
that was the source of the problem. If it was marked as their
"sanding sealer", it would be dewaxed, but probably not recognized as
a viable finish coat material by most.

I assumed that he probably used the other Zinsser (or similar)
products off the shelf, as he is probably not a full time finisher,
because no full time finisher I know would mix dewaxed shellac just to
use in a bathroom. No full time finisher I know would use shellac in
a bathroom to begin with, even with the proper material and mix.

If I was wrong, I hope he pipes in.

That said, I'd use poly on horizontal surfaces in a bathroom just to be
extra cautious.

Me, too. I'd also put poly on all the vertical surfaces as well like
the doors and trims where he mentioned he was having his problems.
Wouldn't give it a second thought.

Robert

On Mon, 10 Mar 2008 21:28:51 -0700, wrote:

On Mar 10, 9:14 pm, Larry Blanchard wrote:

Dewaxed shellac slows down moisture vapor exchange, and thus wood
movement, better than any other finish with the possible exception of
epoxy.

I don't know, but I would be willing to learn if you could point me in
the direction of that information. I thought the post catalyzed 2 K
urethanes with flex additives would be better than shellac, especially
for finishing wood products. No?

Flexner's book calls it "excellent." McNamara:

http://www.woodworking.org/WC/GArchi...cnamara2A.html

calls it "best possible" and Jewitt:

http://www.assoc-restorers.com/r-articles/shellac.html

references a USFPL study that rates it above poly,varnish, and lacquer,
but I couldn't find that study on their website.

Best I could do = hope it helps.

Larry Blanchard wrote:


Flexner's book calls it "excellent." McNamara:

http://www.woodworking.org/WC/GArchi...cnamara2A.html

calls it "best possible" and Jewitt:

http://www.assoc-restorers.com/r-articles/shellac.html

references a USFPL study that rates it above poly,varnish, and lacquer,
but I couldn't find that study on their website.

Best I could do = hope it helps.

Try:

http://www.fpl.fs.fed.us/documnts/te...m-humidity.pdf

--
Jack Novak
Buffalo, NY - USA

wrote:
An old topic, but I am *newly* confused. I installed new doors and
trim, coated with 3 coats of shellac. After just two or three years
the bathroom doors and trim are showing major signs of apparent water
damages, with the finish roughening and lifting, especially around the
upper portions of the doors where the shower steam condenses on the
doors and trim.

Dewaxed shellac is very good at resisting water, but it's not
particularly durable/abrasion resistant compared to varnish.

You might consider one of the waterborne varnishes...less stink and
dries faster.

Chris

Nova wrote:
Larry Blanchard wrote:


Flexner's book calls it "excellent." McNamara:

http://www.woodworking.org/WC/GArchi...cnamara2A.html

calls it "best possible" and Jewitt:

http://www.assoc-restorers.com/r-articles/shellac.html

references a USFPL study that rates it above poly,varnish, and
lacquer, but I couldn't find that study on their website.

Best I could do = hope it helps.

Try:

http://www.fpl.fs.fed.us/documnts/te...m-humidity.pdf

The gory details for that one are at
http://www.fpl.fs.fed.us/documnts/fplrp/fplrp462.pdf.

I don't see anything there to support the contention that shellac will
be superior to a marine-grade 2K polyurethane.



--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

wrote:

An old topic, but I am *newly* confused. I installed new doors and
trim, coated with 3 coats of shellac. After just two or three years
the bathroom doors and trim are showing major signs of apparent water
damages, with the finish roughening and lifting, especially around the
upper portions of the doors where the shower steam condenses on the
doors and trim.


Provided that the shellac you used was dewaxed...

Shellac has good water resistance but is soluble in alcohol, aqueous
solutions of alkali, organic acids and ketones. Although shellac is
insoluble in water it can be dissolved by alkaline solutions such as
sodium carbonate, borax, and ammonia.

I would suspect products used to clean the bathroom, especially aerosol
and spray cleaners as the cause of the problem.

source:
http://www.ams.usda.gov/nop/National...ws/shellac.pdf

--
Jack Novak
Buffalo, NY - USA

On Mar 11, 10:57 am, Nova wrote:

Try:

http://www.fpl.fs.fed.us/documnts/te...ood-from-humid...


I think it is important to study the source as well as its age. While
that information was probably valid in its day, it is over 20 years
old!

The quantum leap forward in polymer resin formulations has been
nothing less than astonishing. Garden variety finishes that are sold
at the big box stores are often (if not always) superior in
performance than the finishes we used to buy as "pros".

I would certainly take that study for what it was worth in its day as
a historical document, not as a fact sheet relevant to today's
finishing protocols.

Robert

On Mar 11, 11:36 am, "J. Clarke" wrote:

I don't see anything there to support the contention that shellac will
be superior to a marine-grade 2K polyurethane.

I honestly doubt that you ever will see anything like that, anywhere.
Shellac has its applications to be sure, but it has it limitations as
well.

Robert

On Mar 11, 10:41 am, Larry Blanchard wrote:

First, thanks for the links. But Larry - I think the sources you
posted did more to harm your premise than to support it.

Flexner's book calls it "excellent." McNamara:

http://www.woodworking.org/WC/GArchi...cnamara2A.html

It does indeed. But it goes on to say:
***********************
Shellac
Although shellac provides the best possible moisture vapor barrier, it
does not resist long term liquid water at all.
***********************

Direct language from your source, which you can see differentiates
between a moisture barrier and a water barrier. Granted that his
article is meant to be an overview and not deal in specific types of
shellac, but in generalities it supports your statement as a vapor
barrier, but refutes your further thoughts on actual water proofing.


calls it "best possible" and Jewitt:

http://www.assoc-restorers.com/r-articles/shellac.html

And also from Jewitt's link under disadvantages:

**********************************
2. Forms white rings on contact with water. This is more of a problem
with shellacsthat have wax and old shellac surfaces.
*********************************

I agree with your statement that it is the plain "waxy" shellac that
causes most of the problem, but again, I am thinking that the OP (who
has probably long lost interest in this) is using off the shelf stuff
which has chemical binders added to it to make it last longer, be more
water resitant and to keep the shelf life up and is not dewaxed.

references a USFPL study that rates it above poly,varnish, and lacquer,
but I couldn't find that study on their website.

Best I could do = hope it helps.

I always like new information. I think the important thing to
remember here is that the information links you posted were taken in
generalties, not in specifics.

At one time there was a denizen of this group (Paddy O'Deen - aka
Patricio Olguin) ) that was a supplier and cheerleader for shellac.
He was able to supply some kind of white shellac that was hard as
nails and pretty damn water resistant. I would have to think that is
what the boat guy in OPs post is referring to, not the Borg stuff.

Robert

wrote in message ...

SNIP I need to refinish the doors and trim as soon as the
weather improves enough to open the windows, but varnish or shellac?
Of course, I prefer shellac, as it is less toxic and dries much
faster, but if varnish is the solution, then I need to use that.

Any ideas and explanations?


Funny thing you should mention.

I just got my latest copy of WOOD magazine and what should appear but the following:

Few finishes survive frequent contact with water.

Kitchen cabinets must survive grease and moisture in air and frequent skin contact around knobs and pulls, and occasional heat.

If you have spray equipment, use a 2-part polyurethane, a pre-catalyzed lacquer, or a post-catalyzed lacquer. Otherwise, brush on an oil-based polyurethane thinned about 10 percent with mineral spirits. Apply at least 3 coats. If you are covering an existing finish, thoroughly clean and scuff it first for a good bond.

I know this applies to kitchens, but it should work for bathrooms as well. Hope this helps.

P D Q

Jeff wrote:
On Mar 10, 9:05 pm, "
wrote:


Perhaps
what you read about boat guy using it was their use of it as primer.

And that, my friends, is the most confusing sentence I've ever
read....


You obviously are not that well read....To be a properly "confusing
sentence" a statement must not communicate its intended point....sadly I've
read enough posts to perfectly understand his intended purpose. Not to worry
with enough time, diligence and patience you too may achieve such heights of
understanding. Rod

On 2008-03-10 19:33:56 -0500, said:

An old topic, but I am *newly* confused. I installed new doors and
trim, coated with 3 coats of shellac. After just two or three years
the bathroom doors and trim are showing major signs of apparent water
damages, with the finish roughening and lifting, especially around the
upper portions of the doors where the shower steam condenses on the
doors and trim.

Here's the question. Recently I read that shellac is actually MORE
waterproof than varnish, and I have read of at least two double-
planked boats in WoodenBoat magazine that have shellac between the
layers of planking because it is believed to be more waterproof.

So what gives? I need to refinish the doors and trim as soon as the
weather improves enough to open the windows, but varnish or shellac?
Of course, I prefer shellac, as it is less toxic and dries much
faster, but if varnish is the solution, then I need to use that.

Any ideas and explanations?

You can put almost anything over shellac. If you want it to be water
proof, I would suggest spar varnish.

On Tue, 11 Mar 2008 15:08:01 -0500, PDQ wrote:

Funny thing you should mention.

I just got my latest copy of WOOD magazine and what should appear but the following:

snip

If I had a nickel for every time I've spotted wrong advice in a ww
magazine ...

The article you reference may or may not be correct, but if the author
isn't one of the well known ww gurus, take it with a grain of salt. And
even then, try it for yourself.

Ronald Warshall wrote:

You can put almost anything over shellac. If you want it to be water
proof, I would suggest spar varnish.

Spar varnish isn't particularly waterproof. It has a higher oil content
so it is more flexible than regular varnish (though not as hard) so that
it can better deal with the wood movement due to humidity variations.
It also has UV inhibitors for outdoor use.

I'm not sure that it has any real advantages for indoor use.

Chris

My goodness! Whatta canna worms!

However, the discussion has been very useful. From the links you
provided and the information in the posts, I have deduced a few
deductions:

1) Shellac may be a good water vapor barrier, but not a good liquid
water barrier when in contact with liquid water, such as condensed
shower steam.

2) Shellac is not flexible, hence is vulnerable to repeated expansion/
contraction cycles, and this is just what one would expect in the
bathroom doors, with repeated humid/dry, cold/warm cycles. Maybe my
finish was developing microcracks and allowing water beneath the
finish.

3) nailshooter41 guessed right, although I didn't "use Zinsser (or
similar)
products off the shelf", I am "not a full time finisher,
because" I DID "mix dewaxed shellac just to
use in a bathroom". Dewaxed orange shellac, purchased from Mr. Paddy
Olguin, 2-lb cut in denatured alcohol, three coats. Took fer-f****n-
ever, but it sure looks nice (except for the doors, of course).

4) Recoating with shellac, although probably pretty easy, is probably
not the best thing to do.

SO, I will recoat the affected areas (2 big doors, 2 medicine chest
doors, and various trim) with some kind of varnish, but not spar
varnish. I would prefer to use a less toxic varnish, and I know that
the technology has improved markedly in the past few years, as we have
a water-based floor finish that has held up extremely well on our red
oak floors. Any suggestions on finishes?

On Mar 11, 8:31 pm, wrote:
My goodness! Whatta canna worms!

LMAO. I like the constructive nature of this thread. Everyone is
civil, and a lot of good information has been brought to light by
different folks.


3) nailshooter41 guessed right, although I didn't "use Zinsser (or
similar)
products off the shelf", I am "not a full time finisher,
because" I DID "mix dewaxed shellac just to
use in a bathroom".

I stand corrected. And I hope you understand my comment was not meant
to offend by any means. Many "non pro" guys turn out great finishes
because they take the time to do all the steps where a pro (ahem..)
might be inclined to skip one if possible.

Dewaxed orange shellac, purchased from Mr. Paddy
Olguin, 2-lb cut in denatured alcohol, three coats. Took fer-f****n-
ever,

Paddy!? Recently? I thought he retired completely to start another
venture and to play with his grandkids. Do you have a recent link or
phone number?

Next time you make a batch up, put the mix in a container with the top
barely screwed on and put the container in a warm water bath. You
will take days off the dissolution. Remember that homebrew shellac
has a relatively short shelf life after mixing with alcohol, but will
last forever as flakes.

4) Recoating with shellac, although probably pretty easy, is probably
not the best thing to do.

Ahhh.. but it is. Now shellac will shine for you if you let it. Sand
off the rough spots on your doors and coat them with the Zinsser
"sanding sealer" which is a dewaxed shellac. This will resolvate into
the existing shellac finish making ti stronger, and provide a bondable
film for your next coating. It will help you negate the effects of
the floating nasties that bathrooms have on surfaces such as hair
spray, spray deodorant, air fresheners, candle soot from those nasty
potpourri smelling candles, etc.

Then apply your new finish coat.

SO, I will recoat the affected areas (2 big doors, 2 medicine chest
doors, and various trim) with some kind of varnish, but not spar
varnish.

There is no point to spar in the bathroom. Doubtful your conditions
are actually THAT extreme.

I would prefer to use a less toxic varnish, and I know that
the technology has improved markedly in the past few years, as we have
a water-based floor finish that has held up extremely well on our red
oak floors. Any suggestions on finishes?

Do not make the mistake of thinking that water based finishes aren't
just as toxic as the solvent based choices. Just because they have
water in them makes them sound benign, but they use ammonias,
formaldehydes, and other nasty things as their solvents.

If you will search around you will find that almost without exception
these days it is accepted that ALL dried finishes are quite low in
toxicity, and at that, you would have to ingest them for harm to be
done.

I personally think the finish will come down to personal preference.
Brush guys have their favorites, and spray guys have theirs as well.

Still, for a bathroom, as others here have said, I would use
polyurethane. My choice would NOT be water based poly (I would rather
breathe fumes from solvent than ammonia) but solvent based stuff.
Most are pretty good, and they all go on about the same so I wouldn't
spend a lot of time finding on particular brand. Benjamin Moore makes
a good one, as does Sherwin Williams.

At the big boxes you can get the Flecto products which are quite
good. Even good old Deft makes a nice one called Defthane.

All of them spray, brush and pad well.

Others will have their thoughts as well, and may be able to get you
exactly what you want.

As always, just my 0.02.

Robert

On Tue, 11 Mar 2008 21:01:29 -0700, wrote:

At the big boxes you can get the Flecto products which are quite
good. Even good old Deft makes a nice one called Defthane.

And Watco has a wiping poly that's worked well for me.

I splattered some shellac on my glasses last weekend. It has not come off
in the shower after 4 days of washing it.

Tonight I tried soaking in a glass of beer. It still hasn't come off. I
guess next I'll have to move up to the vodka.

So, at the very least, I'd say it's pretty waterproof.

Just for clarity sake - shellac *is* a type of varnish. Quoting from
woodweb:

"Non-convertible coatings do not go through a change when they dry and
can be re-dissolved by their original solvent. Shellac, cellulose and
thermoplastic acrylic are such materials.

Convertible coatings go through a chemical change (get converted) and
are no longer soluble in their original solvent.

Within this, there are a number of different types of curing systems.
There are the air-drying or oxidative resins such as alkyd and
urethane oils that use oxygen from the air. This is a slow process
that can be sped up by the addition of metallic soaps (driers)..."

On Mar 11, 12:41 pm, "
wrote:
Shellac
Although shellac provides the best possible moisture vapor barrier, it
does not resist long term liquid water at all.
***********************

Back when I was selling a metric ton of shellac per month, one of my
most loyal and interesting clients were those making wooden whitewater
canoes. They would buy only the finest Kusmi buttonlac (somewhat of a
contradiction in terms, as buttonlac is minimally processed, and
contains wax, bug parts, bush parts, etc.) to apply to the outsides of
the hull. They did this for three reasons:

1. Shellac is the only thing that will slide over rocks.
2. It was resistant to water (cold).
3. It was durable, and yet easily renewable.

It was the *only* stuff they would buy. Buttonlac is processed by
heat (wrapped in burlap and then heated over a fire until molten), not
solvent, and so it is polymerized. Advanced users would either
separate it in a centrifuge (in solution), or double-wrap a wad of
buttonlac in some commercial filters, submerge in alcohol, and then
wait a few weeks for the precious finish to seep out.

At one time there was a denizen of this group (PaddyO'Deen - aka
Patricio Olguin) ) that was a supplier and cheerleader for shellac.

That would be me. All the stuff I sold was filtered, not bleached,
and thus the ability to retain most of the water resistance properties
it originally had.

Someone else mentioned that shellac isn't flexible. I've had the
opposite experience. One of my favorite parlor tricks was to take a
client's business card (at the beginning of lunch, say), dip it into a
handy jar of orange shellac, and then at the end of lunch, bend the
card into a circle without the then-dry finish cracking. It loses
flexibility after perhaps 100 years or so... don't we all?

Paddyo

p.s. There are a few people that are distributing the same product I
used to. shellacshack.com is one of them. I did receive some free
samples from the guy when he was looking for verification of his
product, but other than that, no affiliation. It ain't as cheap as I
used to sell it, but a durned sight cheaper than most I'd say.