Outdoor finishes questions

[Bill Jobe]

I have a few questions regarding clear outdoor finishes. My shutters are sanded back down to bare wood after just one year.
First of all I read that oil base is superior to poly. Is it?
Is applying acrylic really important as a first coat if several coats of clear coat will applied?
One site I looked at mentioned paint base of some kind. Before pigment is added.
Is that acrylic paint and is that what is used?
And finally, what single product, by brand, contains the highest level UV block/obsorb?
I am ok with a yellow shift.

[Jim Becker]

Just as an aside, you say/ask: "I read that oil base is superior to poly. Is it?" "Poly" refers to polyurethane resin and there are both oil based and water borne products that contain polyurethane. So the obvious answer to your question requires specific products to compare. Water borne products are all acrylics, even when they contain polyurethane resin in whatever concentration the manufacturer did. Theoretically, my understanding is that an oil based polyurethane varnish "may" be more durable than a water borne product because the former is created by heating to transform the individual ingredients from what they are into varnish. Water borne finishes are not made quite the same way. And polyurethane itself's primary benefit is abrasion resistance. But many modern water borne products are pretty darn good compared to a decade or more ago.

That all said, if you are intending for your wood shutters to stay looking like freshly milled, new wood, it just isn't going to happen for anything more than a short period of time, regardless of the level or UV protection in the finish. UV protection "helps" with the length of time, but the natural greying of wood outside is also from oxidation, not just UV. And with a film finish, you also can get staining from water if the film cracks in any way. Paint or stain with whatever level of transparency you prefer is a better outdoor finish for wood than a clear film oil based varnish or acrylic water borne finish. Some folks prefer a penetrating oil product like Sikkens for outdoor wood that isn't going to be colored. In all cases, regular maintenance is going to be on your calendar.

Regarding your question about deep tint base exterior paint used as a clear, some folks have posted about that historically. Deep tint base is pretty much clear and as an exterior product, it's likely UV stabilized. I have not personally used it.

[Bill Jobe]

Thank you, Jim.
Another question I meant to ask was with regard to type of look desired. I want a satin finish. Some say use glossy on all but the final satin coat will render the greatest grain depth while others claim several coats of satin will have greater UV protection .
Will several coats of satin last longer but dull the grain more than all glossy with one coat of satin, the latter looking better from the start but not lasting as long?

[Bill Jobe]

As a test, I did her window boxes with several coats of Hellman's Clear Satin and plan to use what is believed to be the best there is on the shutters.
Perhaps a year or 2 from now I'll know what to use next time.
By the way, with several coats of clear, when the wood begins to fade, does all of the finish need removed and redone or will fine sanding and more coats do the same thing?
I spent nearly 7 hours yesterday just sanding 6 shutters down to bare wood.

[John TenEyck]

As Jim said, clear film finish for exterior work is a recipe for never ending maintenance. Ask the owner of any boat with exterior wood. But if you just have to have a clear finish you would be far better served with a marine varnish, like Epifanes over an epoxy primer, than Helmsman. It will take 7 coats of Epifanes and at least one additional coat every year to maintain it.

John

[Bill Jobe]

Thanks everyone.
John I googled epoxy primers and this came up. http://mgmt-www.sherwin-automotive.c...thane-primers/
Not saying you are wrong. I'm simply looking for the truth.
Each year you simply sand lightly and add a new coat?
I could live with that real easy.
Here's what I'm trying to preserve.

[Bennett Ostroff]

I would strongly consider painting them. A hardware store or Lowe's/HD will help point you in the right direction for a good exterior paint.

[Bill Jobe]

I would strongly consider painting them. A hardware store or Lowe's/HD will help point you in the right direction for a good exterior paint.

Not gonna happen.

[John TenEyck]

Bill, your link goes to info. that is mostly out of context in that it's for metal substrates. But it is correct that epoxies will degrade with exposure to UV. That's why you have to topcoat them with a UV absorbing varnish like Epifanes. Take a look at this link: https://www.multiwoodprime.com/

John

[Bill Jobe]

What is the best epoxy for a first finish?
Can it be made into a thickness that can be b rushed or rolled on?
I'm considering passing on a coat if epoxy due to time restraints.
I can add layers of Epifanes.
By the way, which version of their product should I be considering?
Also, I want a satin finish but I have not seen it in that brand.
Should I apply 5 or 6 coats of Epifanes and one coat of satin of some sort?

[John TenEyck]

I don't know if this is the best epoxy primer under Epifanes, but many folks say it's very good: http://www.smithandcompany.org/products.html

And there is always West Systems Epoxies: https://www.westsystem.com/instructi...nish-coatings/

Epifanes Clear Gloss Varnish:

https://www.jamestowndistributors.co...duct.do?pid=92

Epifanes Wood Finish Matte Varnish: https://www.jamestowndistributors.co...ct.do?pid=4123


John

[Edwin Santos]

Hi,

I too like satin finishes, but the people at Waterlox told me their marine varnish only comes in high gloss because the gloss is part of the system of UV protection. In other words higher reflectivity means greater UV resistance.

However I notice on the Epifanes website that they make a product called Wood Finish Matte which is designed to go over their gloss varnish, so it appears you can do what you are seeking with their product line. Maybe shoot Epifanes an email and seek their guidance. If you do this, please post back with an update on whatever you learn.

Edwin

[Bill Jobe]

There are simply too many products. I can't get my head around all the hype.
Meanwhile the 3 pairs of shutters are down to bare wood and sanded to 220 and leaning against the inside shop wall.
I covered them with plywood to protect them from indirect uv.
For now I am at a standstill.

[Steve Schoene]

Smith (exact name escapes at moment) is a low viscosity epoxy designed exactly for this use. It’s available at Jamestown Distributors. It really adds durability since it reduces moisture and oxygen penetrAtion. Top coat with Epiphanes

[John TenEyck]

Smith (exact name escapes at moment) is a low viscosity epoxy designed exactly for this use. It’s available at Jamestown Distributors. It really adds durability since it reduces moisture and oxygen penetrAtion. Top coat with Epiphanes

Follow the link I posted in my last message. Same thing for both the gloss and satin sheens of Epifanes.



John