Shutters/tung oil finish

[Bill Jobe]

Last year I made shutters for our large window in the front of the house and the wife is very pleased with them. BUT, I gave them 3 coats of tung oil finish thinking I was doing it right. Now I've come across info that says to never use that for any wood ourside. I made them from very nice wood....no sap wood at all and the finish does look nice. My plan was to take them down each year, lightly sand them and add one or 2 more coats of the tung finish.
Did I mess up?

[Stan Calow]

What is the actual brand of "tung oil finish" that you used?

[Bill Jobe]

Formsby. Made by Minwax. Suppose it's the same stuff?

[Steve Schoene]

tFormby,s is a brand, as is Minwax, owned by Sherwin Williams. Formby's Tung Oil Finish is an interior varnish, not tung oil. Minwax Tung Oil Finish is entirely different and consists of an oil/varnish mix. Neither would be a good choice for exterior shutters. At this point I would top coat your finishes with a good exterior (Marine) varnish. I'd prepare for that with a somewhat more vigorous sanding that you had had in mind. The marine varnishes would have to be obtained from a boating supplies store. I'd choose from brands such as Epifanes Gloss (relatively dark amber) Interlux Schooner, or Pettitt Captains. Follow label directions, except you may need to thin a bit. These are dramatically better than similar named products in big box stores or ordinary paint stores.

[Jim Becker]

Formsby. Made by Minwax. Suppose it's the same stuff?

'Gotta love marketing names, but that product is simply varnish...and an interior varnish, too. It's not a "tung oil" product in the sense that even if they used some tung oil in the formulation, once it's cooked into varnish, it's no longer tung oil. Your best bet for projects like this is an exterior focused product when you re-coat. Do note that you will still get the gray-out of the wood from UV and exposure regardless unless you completely sand to bare wood periodically and refinish. If you do sand back, you might want to consider a penetrating exterior product rather than a film finish.

[lee cox]

Tung oil does not have UV inhibitors in it so sunlight breaks it down. I tried Teak oil which is suppose to have the UV protection in it on some oak smoker handles I made. It does not seem to stand up to Texas sun.

I owned a sail boat in the past. The teak needed to be varnished every 4 years. Spar varnish will last but needs to be completely sanded off before refinishing after 4 years in Texas sun. There was a guy at the boat yard which was experimenting with poly. He said you could lightly sand and apply another coat without completely removing the finish. I never used it as I sold my boat.

[Bill Jobe]

Well now I'm in a pickle. She wants shutters for the 2 smaller windows in front. What are the chances thet'll look like the tung oil finish ones? Is it unlikely that I can remove all of the tung oil finish so they look alike or should I use the same screwball process with the next 2 pairs?
Not sure where I read it, and it may have been sarcasm, but they suggested as a final finish to prevent uv damage was to mix a high uv rated product for the skin mixed in a good wax, then buffed.
I'll accept mockery because I really don't have any answers. I went to a sawmill and bought very nice 4/4 cedar that is all heart wood. What would you do.

[Bill Jobe]

Kiln dried

[Stan Calow]

Bill, not getting much response, here. I am not an expert, just a homeowner dealing with outdoor wood issues for years. I think the bottom line is that there is no maintenance-free outdoor finish that will work. Everything (even spar varnish) will need touching up and re-coating every few years. The best finish to try is a deck finish like Thompsons, Olympic, Cabot or other brands that are designed and intended for outdoor use. They won't last forever, but do have some UV and water resistance to them. The more pigment the better, with the best being - paint.

I wouldn't bother trying to take off what already you put on. I'd just overcoat with deck finish and hope for the best. I've heard the suggestion of using sunscreen or Armor-all too, but those ideas makes no sense. They won't last long before wearing off either. The color change in wood is also about moisture and oxygen, not just UV.

I'm hoping you get better input here, but wanted to say something based on my experience.

[Malcolm McLeod]

Sikkens Cetol has given fairly good exterior results (on a front door with southern exposure to full Texas sun and rain). There are a lot of variants to their Cetol product line now, and not sure exactly which I used ~8 years ago. (I recently sold the house, or would be looking at re-coating soon.)

Edit: As for matching the 'tung oil' finish, the Cetol product I used gives much the same wetted, in-the-wood look as tung oil. I doubt you'd notice much difference.

[Bill Jobe]

Thank you, Stan. I appreciate your comments.
I had it in my head that all I had to do was simply a light sanding followed by another coat of tung oil FINISH every spring. Thought I had picked the best product.
Live and learn (well,some do. Me? Not so much).
The window box that I made out of Menard cedar 2 years ago and coated with polyurethane still looks brand new.

[Bill Jobe]

This may sound nuts, but at this point couldn't I apply anchorseal thinned a bit with mineral spirits? I mean, I don't really want people hanging around right in front of my house anyway, so who would know?

[William Fretwell]

The Cetol product is used on sailboat teak a lot. Usually 3 to 4 coats annually. Once you use it you are committed to it really. It is a stain and sealer. The Epifane varnish is one of my favourites and lasts longer outside with more UV inhibitors. The application is key, I would follow the instructions! Don't do what you always do!
Any wood outside like that in the sun & weather is a make work project. Perhaps white cedar would be a better choice and just let it gray.

[Bill Jobe]

Thanks guys. Glad I caught your info early. Last week I forked out $400 for a truckload of this cedar. The wife wants more shutters, more window boxes. The daughters want window boxes...... I is all the red color, no white at all. That will resist rot for a long time with or without a finish, won't it.
Frankly I'd rather be on my little HF mini, but I take my kudos where I can gettem.

[Malcolm McLeod]

The Cetol product is used on sailboat teak a lot. Usually 3 to 4 coats annually. Once you use it you are committed to it really. It is a stain and sealer. The Epifane varnish is one of my favourites and lasts longer outside with more UV inhibitors. The application is key, I would follow the instructions! Don't do what you always do!
Any wood outside like that in the sun & weather is a make work project. Perhaps white cedar would be a better choice and just let it gray.

I see there are now 'Marine' and 'Door & Window' versions, as well as others (...that I didn't read literature on today). I assume I used 'Door & Window', but not sure that is what it was called at the time. I know for sure it wasn't tinted/pigmented stain. I also recall the big selling point was Cetol's long-term flexibility, and I certainly won't complain about the 8 years I got out of 2 (3?) coats. So, is there much difference between the Marine vs. D&W?

Also, it looks like both are promoted as a transparent base. I have to assume again, but could OP not use it in it's 'un-tinted' form? Or does this compromise the UV resistance of the coating or the UV protection of the underlying surface?