# Spar Finish Flaking @ 18 months.



## BrownsFan (Jul 11, 2011)

I built this chair a year and a half ago.
http://lumberjocks.com/projects/65910

It now looks like this:









Here's a close-up of the arm:









Is this typical? Why is my finish peeling?


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## Loren (May 30, 2008)

Well, 18 months is a disappointing run for outdoor spar
varnish, but not unheard of. It's the light that makes
it do that more than the moisture I think. Paint is
obviously easier to maintain. If you want to do the
varnish again, I suggest getting some chair covers
for when you aren't using them.


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## distrbd (Sep 14, 2011)

Isn't spar varnish designed for boats to protect the surface from moisture and UV rays?I'm no expert but it looks like the moisture content in that wood was too high and the spar did not allow it to breath .


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## kajunkraft (May 7, 2012)

Not that I claim to be an expert in this area, but I've always heard that UV from the sun needs to be reflected (deflected?). For this to happen there has to be some pigment in the finish (ie: not just a clear finish). Thompson's Water Seal, for example, is something that always comes to mind for outdoor projects and they now promote a UV "inhibitor" for their finish. I build mainly outdoor furniture and use Ready Seal pretty much exclusively, although I'm sure others are pretty good too. I have never experienced the cracking/peeling that your pictures show. Nevertheless, there seems to be a lot of interest in a "shiny" finish, which I have not yet figured out how to achieve for outdoor furniture.


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## LeeBarker (Aug 6, 2010)

Ken, my understanding is that spar varnish is more flexible than regular varnishes so the exterior wood can expand and contract without affecting the finish.

Also, wood does not breathe. It takes in moisture and releases it as humidity and temperature vary.

This case is severe. I suspect, in addition to the UV damage, that the wood may have been moisture rich when the finish was applied. Eric, did you have a moisture meter reading on the cedar before you built the chair?

Beautiful workmanship, by the way. I looked at your Projects page.

Kindly,

Lee


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## BrownsFan (Jul 11, 2011)

No moisture meter. I purchased the cedar in the summer months right from the homecenter…. nothing fancy.


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## gfadvm (Jan 13, 2011)

I suspect that is Spar Urethane rather than true Spar Varnish as I have had the exact same experience with MinWax Spar Urethane on chairs in my barn. They haven't ever gotten wet but are exposed to direct sun for most of the afternoon.

True Spar Varnish is a different breed of finish that I have no personal experience with but am told that it is used in marine applications.


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## pintodeluxe (Sep 12, 2010)

I won't build outdoor wood furniture for this reason.

I have not had good luck with spar finish. We used it on a door many years ago. Someone taped a mail notice on the front door with scotch tape. When we removed the tape it peeled the finish right off.


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## BrownsFan (Jul 11, 2011)

Just checked the old can. Yes. It is Varathane Spar Urethane. The chairs sit out year-round.


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## Loren (May 30, 2008)

My folks have a cabin in the mountains. 2 doors down there
is another the owner finishes with spar varnish. The side
that gets the sun gets devastated while the shady sides
hold up a lot better. It snows up there too, which 
only makes the situation worse I imagine. The place
looks gorgeous when the varnish is not peeling off.

Every year on a boat I think you go over every varnished
surface with a wire brush, sand and recoat. The salt
air is the worst, combined with the sun hitting it.


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## Dusty56 (Apr 20, 2008)

Just part of an article about "spar" varnishes and urethanes:
http://www.hardwoodlumberandmore.com/Articles/ArticleViewPage/tabid/75/ArticleId/1/Marine-Varnish.aspx

"Now, lets take a look at the marine varnish pretenders-the so-called "spar varnish" made from linseed oil and urethane resin. "Spar Urethane" varnish should be avoided in any exterior application in which even moderate exposure to direct sunlight is likely. We need look no further than the properties of varnish made from urethane resin (polyurethane) to understand why. Urethane resin varnishes suffer two weaknesses that have direct bearing on varnish used in exterior applications in general, and marine applications in particular.

First, urethane resin is highly subject to UV damage. Polyurethane will begin to yellow, develop hair-line cracks, and loose adhesion with the wood very quickly in a full-sun environment. Soon thereafter it will begin to flake and peel from the surface. The more popular spar urethane varnishes can be expected to completely fail in as little as a single season in a full-sun environment. Even in moderate sun they are likely to last no more than a couple of seasons."


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## distrbd (Sep 14, 2011)

Mr Lee Barker,thank you for pointing out my mistake of using the wrong terminology,my point was that it looked like the moisture content of wood was high and the spar varnish might have trapped it in the wood in other words it did not release the moisture it had taken in,like you said*"the wood may have been moisture rich when the finish was applied."*
Loren I had no idea direct sunlight would destroy the spar varnish,I had heard wood surfaces with 2 part epoxy should not be left under direct sunlight,but never knew that about spar varnish.


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## BrownsFan (Jul 11, 2011)

Dusty. You are definitely describing what I am seeing.

Does anyone have a good alternative recommendation for cedar outdoor year-round?

Shellac?


> BLO


?


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## jumbojack (Mar 20, 2011)

were these fence boards?


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## Loren (May 30, 2008)

Paint.


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## shipwright (Sep 27, 2010)

-Red Cedar is notorious for not taking finishes well even paint. It's natural oils just don't like it.
-UV rays actually attack and degrade the surface layer of wood cells under a clear finish and cause adhesion failure.
-All bright finishes on boats are an ongoing maintenance situation.

Things that have worked for me are:

1)With red or yellow cedar and with oily wood in general you can stabilize the surface by applying a coat or two of S1 epoxy sealer (System Three). It has a high level of lacquer thinner and can penetrate and seal the surface. follow that with your high UV resistant clear finish. Revisit the topcoat annually…. sand , repair, re-coat.

2) Cetol (Sikkens)


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## avra (Dec 25, 2013)

Thanks Dusty56 for that great link. 
Nice chairs Eric, but it looks like the finish is toast, and burned toast at that. 
On future outdoor projects, consider an oil finish, preferably one like Penofin formulated for UV resistance. No film finish means no adhesion, cracking or peeling issues. Ever. Just 10 minutes to rejuvenate with a wipe rag. Cedar, being inherently rot resistant, does not really require any finish at all except for cosmetic purposes. Left unfinished, it will turn silver and acquire a protective 'skin' of UV degraded surface cells. So long as air circulation is adequate to prevent mildew and rot, cedar is an excellent choice for outdoor furniture precisely because it does not need to be sealed. However, an oil finish will help retard UV beaching and enhance water repellence.

To salvage what you've got, I'd take a random orbit sander and start w/ 60 grit, concentrating on the visible surfaces: backrests, seats and arms. Let the wood dry out for week or two indoors and apply an oil finish that will at least help bridge the areas that still have varnish. Expect that varnish to continue to degrade. Next season the sanding will be quicker over damaged areas, and a quick wipe w/ oil will make your project handsome again. After a few seasons, you will have ridded yourself of the majority of your poor choice of finish! Live and learn. Welcome to the club!

Don't drive yourself nuts trying to get a perfect finish. The design is great and the chairs look really comfortable. That is at least a third base hit! Work on getting the film off over a couple of seasons. Shouldn't take more than 30 min. of sanding on each chair. Put a little oil finish on, sit back and enjoy the view!

just my three cents…

PS: When doing brightwork, as it is called, on boats… multiple thin coats of a well formulated varnish are far superior. Initial coats are thinned considerably, working up to full strength. Weather must frequently be considered when applying finish outdoors. Humidity, direct sun, etc. Half art, half science and the other half guesswork.


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## wapakfred (Jul 29, 2011)

Urethane finishes should not be outside, urethane and UV do not play well together. Most of the box stores "spar varnishes" are only imposters. (I know this has all been mentioned earlier). Anyway, a real marine spar varnish is what you need….Epifanes is normally considered the best available. If you ,ilive in an area where you can still get oil based paint, another good coating would be untinted paint base. The highest number in the line, typically #4, without tint will dry to look very much like an oil based varnish. But it will have UV inhibitors, no urethane resins, and hold up very well. It will also be less expensive than some other stuff. Should you choose that route (paint base) test it at the store first, open a can and put a stir stick in it and wipe it off. That should tell you what the finish will look like. Of course also mentioned above was paint itself, which is the best outdoor coating.


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## thedude50 (Aug 13, 2011)

I have to agree with ship wright on this. a quick sanding and a new application is what id do. if your climate is hot then very cold you may have to do this every couple of years. this is one reason I like Redwood over cedar.


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## BrownsFan (Jul 11, 2011)

So its spring again and I'm building another Adirondack chair. I really really like the finished look of my original (spar) finish. I do not prefer the natural weathered look. Here are 5 ideas….good/bad?

1) I'm guessing lacquer is another poor choice. ???

2) What about an automotive clear coat with hardener finish? It doesn't have any wide panels with large seasonal movement.

3) Shellac on cedar for outdoor use???

4) Where does Thompson's Waterseal fit in the picture? Any UV protective properties?

5) And finally… B.L.O.?


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## gfadvm (Jan 13, 2011)

Any clear film finish will eventually crack and peel if left in the sun. Epiphanes is supposed to be the best of all the exterior film finishes.


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## ElChe (Sep 28, 2014)

Penofin marine finish is awesome but expensive. I would avoid a film finish. I bet you could card scrape a lot of the finish off before sanding. Good luck.


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## OSU55 (Dec 14, 2012)

That looks typical for any clear "spar" varnish. It's the UV that does the damage. Any exterior finish that will be in the sun must have pigment to block the UV, or it will look just like your pics. Either paint or opaque stain are the only reasonable choices. Many bring up various marine finishes. Take a look at the wood of a boat with a clear finish that has sat outside in the sun for a few years - pretty ugly.


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## runswithscissors (Nov 8, 2012)

For 18 years I kept a sailboat year-round in our local marina. I finished the spruce mast with a Behr product called Liquid Rawhide. Its UV resistance was very good, plus it held up well to all the stuff the various seasons could throw at it. You could touch it up simply by cleaning the area in question and recoating-no sanding necessary. I could typically go 3 or 4 years without having to do a major scrape down and refinishing. It did not peel or blister.

My cabin sides were clear cedar (western red), and I finished those with oil, which was quite satisfactory as long as I didn't let it go too long. Oil also on the teak trim (teak, being oily, doesn't hold varnish well).

Never tried the Liquid Rawhide on cedar, so can't speak to that. One downside to it is that it is not a very hard varnish. But its resistance to all kinds of weather was impressive. I don't know whether they make it any more.


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## pjones46 (Mar 1, 2011)

Penetrating transparent oil stain for decks can be used as it is color safe for clothes once dried. Easier to recoat and maintain.


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## AlaskaGuy (Jan 29, 2012)

Behr Liquid Rawhide made it rounds here in Alaska some years ago. Didn't work as well here as it did for you.

Eventually there was some class action suits over that product and one other one. Don't know it they remeided that problem or just quite making the product.

https://www.google.com/search?q=Liquid+Rawhide&ie=utf-8&oe=utf-8


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