# Outdoor finish Spar Urethane alternative?



## oak bench problems (Jun 25, 2014)

Last spring I found a pair of antique, cast iron, garden bench ends. Great, I can do this. The metal work took some time but came out great. The first mistake was using Red Oak for the new slats(I am a novice). After staining, I applied three coats of Helmsman Spar Urethane, as it would be exposed to rain, sprinklers, and sun. The bench has a western exposure and is against a brick wall. After six months it was apparent that the Helmsman was not holding up as advertised. It seems that the areas that were exposed to the sun were most affected. I was left with a ugly, weathered bench.
I decided to use Jasco, Varnish and Stain Remover following the directions. I wasn't pleased with the results. I still have some areas that have retained the original stain pigment and others with black marks. After a final rinse with water and bleach, I now have more black water stains, which I now know that I need to remove with oxalic acid. I have sanded all surfaces with 60 grit and have removed some of the black stains. 
WHERE SHOULD I GO NOW?
Are the products not working well because I live in California where there are laws requiring low V.O.C.'s?
I don't want to go through this process every year. 
Any suggestions?


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## Steve Neul (Sep 2, 2011)

I'm surprised the Helmsman didn't hold up better than that. I've made thousands of bench slats and used the helmsman for the finish and never got any complaints. Because of the cost I was also making the slats out of red oak. White oak would be a much better choice of wood for what you are doing and there is better spar varnishes than Helmsman. The best would be Penofin. It's available at places that sell boat supplies. Another one I like that is cheaper is Cabot Spar Varnish. It is also a marine grade spar varnish. I wouldn't use any kind of oil finish for a bench as the finish could rub off onto clothing.


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## oak bench problems (Jun 25, 2014)

I was surprised also that the Helmsman didn't hold up. I have used it in the past with great results. I don't think it was an application issue because the finish on the back of the slats that were not exposed to the sun held up fine. I do know that many products used in California, especially the S.F. bay area had to reformulated to comply with new V.O.C. regulations. 

Thanks


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## cabinetman (Jul 5, 2007)

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Spar varnishes are designed to put a film finish on outdoor wood. Some are better than others. They all will fail, some sooner and some later. My complaint with them is that other than common sense concerning the physical aspects of wood and its condition, when you encapsulate wood used outdoors it goes through some physical changes.

With the differential in temperatures, and humidity, the wood having an amount of air within, can't expel or accept air as it goes through its adaptation to the environment. So, simply speaking, envision wood that has been sealed reacting to its environment. Air expelled is beneath the film, and can't exchange. So, what happens is that the finish starts to fail. It may release from the wood, or just break down from the outside in. It will get cloudy and crusty, and may peel away in layers after a crack develops.

There are alternatives to an outdoor film finish, but for those that expect to see a shiny surface, they may be disappointed.






















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## Steve Neul (Sep 2, 2011)

oak bench problems said:


> I was surprised also that the Helmsman didn't hold up. I have used it in the past with great results. I don't think it was an application issue because the finish on the back of the slats that were not exposed to the sun held up fine. I do know that many products used in California, especially the S.F. bay area had to reformulated to comply with new V.O.C. regulations.
> 
> Thanks


With the environmental restrictions you have you might have to go with a marine grade epoxy finish. I think it's available in California. I don't have any first hand experience with it but from what I read it's comparable to a marine grade spar.


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## Fred Hargis (Apr 28, 2012)

Your experience with Helmsman doesn't surporise me. Any finish that has urethane resins just isn't going to do well outdoors. If you want to stay with a clear film finish (in California) your only choice may be a true marine spar varnish. One often mentioned is Epifanes, but there are several available. They will have UV inhibitors as well as being made from other than urethane resins. Waterbornes should be easily available there, and one I haven't tried but read really good things about is GF Endurovar. Bear in mind any clear film finish will need to be redone at some point, these choices will give you the longest life.

PS, just a note about waterborne finishes. They are predominantly acrylic resin finishes, but apparently for marketing reasons many of them have added a small amount of urethane resins...and then put that on the label or in the name. The amount is small enough that the acrylic resins still do a good job.


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## Steve Neul (Sep 2, 2011)

Everything I've read says all oil based spar varnishes are banned in California. I suspect the helmsmans the OP used may have been a different brew.


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## HowardAcheson (Nov 25, 2011)

Where to start?

First, any finish containing urethane is a poor choice for exterior use. The UV in sunlight rapidly attacks the urethane and the finish will quickly fail. First it will become cloudy then begin to crack and peel. Minwax Helmsman Spar Varnish is one of the poorest performers in a number of tests. No professional marine finishers I know use finishes containing urethane for exterior applications.

Chemical paint strippers frequently do not remove all the finish with a single application. The tannin in oak reacts with most metals particularly when it is in contact with water creating black stains. Chemical paint stripper will not have any affect on the black stains left on the oak. Oxalic acid is the bleach used to reduce tannin stains. But, depending on the severity of the stains, the bleach may not be completely effective. Go through the bleaching process a few time for the most complete removal.

The chemicals in water will also cause black stains in oak. 

Sanding with 60 grit paper is not very productive. It will not affect the black stains that are deeply absorbed into the wood.

Someone suggested epoxy as a finish. That's not a good idea. Epoxy is also quick destroyed by the UV in sunlight. Epoxy is sometimes used on marine applications but it is then over-coated with a non-poly oil based marine varnish to protect the epoxy.

You best choice as a finish is to use a non-poly marine varnish. Go to a true marine supply store and look for brands like Interlux, Pettit or, best of all, Epifanes. You will not find a good product at a big box store.


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## oak bench problems (Jun 25, 2014)

:icon_eek:Thank you for all your information, all the black stains are now gone. I looked into Epiphanies and it is expensive. What are some of the non film options? The bench is more for decorative purpose than use. I was considering Cabot Australian Timber Oil, which is a combination of linseed, long oil alkyds, and tung oil. Any opinions would be welcome. Keep in mind uv seems to be my biggest concern.


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## cabinetman (Jul 5, 2007)

oak bench problems said:


> :icon_eek:Thank you for all your information, all the black stains are now gone. I looked into Epiphanies and it is expensive. What are some of the non film options? The bench is more for decorative purpose than use. I was considering Cabot Australian Timber Oil, which is a combination of linseed, long oil alkyds, and tung oil. Any opinions would be welcome. Keep in mind uv seems to be my biggest concern.


You might consider Penofin Red Label. It comes in clear, and colors...has a high UV factor.


















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## Steve Neul (Sep 2, 2011)

oak bench problems said:


> :icon_eek:Thank you for all your information, all the black stains are now gone. I looked into Epiphanies and it is expensive. What are some of the non film options? The bench is more for decorative purpose than use. I was considering Cabot Australian Timber Oil, which is a combination of linseed, long oil alkyds, and tung oil. Any opinions would be welcome. Keep in mind uv seems to be my biggest concern.


With all the trouble you are having it might be a good idea to replace the wood with white oak instead of the red oak. White oak will weather better. The Cabot oil finish would be about as good as you can get for oil finishes but it won't give you any better protection then the Helmsman. It would be necessary to constantly re-apply the oil to maintain it. You could have touched up the Helmsman from time to time about as easy. 

If you go with the oil finish put some in a container and stand the slats up in the oil and allow the finish to penetrate into the ends. The ends are what is most vulnerable.


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## cabinetman (Jul 5, 2007)

oak bench problems said:


> :icon_eek:Thank you for all your information, all the black stains are now gone. I looked into Epiphanies and it is expensive. What are some of the non film options? The bench is more for decorative purpose than use. I was considering Cabot Australian Timber Oil, which is a combination of linseed, long oil alkyds, and tung oil. Any opinions would be welcome. Keep in mind uv seems to be my biggest concern.


You might read post #4 again and consider how a film finish fares with outdoor exposure.


















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## oak bench problems (Jun 25, 2014)

Ok, I admit that I am a novice, but, I thought when reapplying oil, I would only have to re-scuff the surface, and apply new coat. As I understand, with a film finish, if it's failed in some areas, the whole surface needs to be sanded or stripped. Am I wrong? Could be, I admit that I am a novice. I did reread post #4 , and I am from California, we like every thing to breathe, including our wood, but at the same time it is frustrating to preserve it. I don't need a gloss finish, just a way to preserve my bench, with the least amount of time. I know that I need to provide upkeep, I just wanted to figure out the best way to "geter done".

Thank you for all of your advice,
it is welcome and feel to comment


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## cabinetman (Jul 5, 2007)

oak bench problems said:


> I don't need a gloss finish, just a way to preserve my bench, with the least amount of time. I know that I need to provide upkeep, I just wanted to figure out the best way to "geter done".
> 
> Thank you for all of your advice,
> it is welcome and feel to comment


IMO, a penetrating oil finish is a much easier upkeep than a film finish. Just clean and re-apply...no sanding.








 







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## Steve Neul (Sep 2, 2011)

oak bench problems said:


> Ok, I admit that I am a novice, but, I thought when reapplying oil, I would only have to re-scuff the surface, and apply new coat. As I understand, with a film finish, if it's failed in some areas, the whole surface needs to be sanded or stripped. Am I wrong? Could be, I admit that I am a novice. I did reread post #4 , and I am from California, we like every thing to breathe, including our wood, but at the same time it is frustrating to preserve it. I don't need a gloss finish, just a way to preserve my bench, with the least amount of time. I know that I need to provide upkeep, I just wanted to figure out the best way to "geter done".
> 
> Thank you for all of your advice,
> it is welcome and feel to comment


Any finish is going to fail. It comes down to maintenence. An oil finish will frequently need to have the oil re-applied. You have to watch it and if at any time the maintenance is lacking it will let water into the wood staining it or allowing the wood to rot. Then it will either have to be refinished or replaceed if the wood is allowed to rot. An oil finish is better suited for woods that naturally repel water like cedar. 

With a spar varnish it will completely free of maintenance for usually the first two years. The spar is a protective coating which will shed any water exposure. Then when the finish starts looking dry it can be scuff sanded and have another coat of varnish applied. It normally just takes an hour or two to do this. Then it will be maintenance for another year or two. It's the folks that varnish a door and wait six or seven years until the finish is flaking off that have the problems. Still the original coat will eventually flake off and when it does that is just a weekend project to refinish and you can forget about it for a couple of years.


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