We have a new mahogany exterior front door that we we stained and finished with two coats of tung oil. This weekend we noticed that the the door is fading pretty bad. Its only been six months since we finished the door. Any ideas what might have happened?
Edited 5/23/2005 9:51 am ET by wvjack
Replies
Tung oil does not provide protection against UV rays and must be topcoated with a sealer such as exterior polyurethane or similar. This degradation in finish occurs even quicker if your door faces south.
Thanks,
Do I need to sand and restain to apply the exterior sealer?
I have to disagree with acorn. I've used exterior poly, and varnish on exterior doors that have held up for years. Varnish is a better choice as it is more flexible, but ultimately every finish exposed to the elements will need to be re-done.
As stated by someone else, wipe the door with mineral spirits apply tung oil again and when dry apply your topcoat.
Polyurethane is one of the worst finishes for exterior work, worse even than Tung oil. It will fail - as do all exterior wood finishes - and will crack and peel when it does, necessitating a scrape and sand and chemical removal and total refinish of the door. I would try a test corner 3" square to see if the Cetol will adhere ok. I'd do mineral spirits woipe down first, perhaps with a fine 3m pad.
Use Sikkens Cetol 3 coat System for exterior doors and windows. It was developed for the very strong European door market, and designed for easy recoating. I tell my customers to use a .39 cent foam brush and recoat on a Saturday morning, and you can lock up at sundown.
Long story short, I'm a professional doormaker for 30 years. Along with that, I'm a door finish debunker also.
http://www.acornwoodworks.com go to the page on "Doors" Most of thses are Sikkens finishes.
Your work is stunning. Do you do the designs as well as the construction?Thanks for Sharing.
Mark
Measure it with a micrometer, mark it with chalk, cut it with an ax.
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Mark - Thanks for the compliment. 50% of our work is interior and exterior doors and windows. The work is anywhere from fully detailed by architects to sketches on cocktail napkins or magazine pics. I often will adjust a design to fit in with proper proportions, or to tie in with other work nearby.
I have done this type of work for 29 years. 15 years ago I walked out of a 20 man residential millwork shop I was running and went to work in the back yard in a 1000 s/f shop I built. 6 years ago we moved into 4500 s/f to do larger projects. We will be moving this Fall to 7200 s/f and adding a few more people. I used to build it all, now I mostly detail, organize and cheerlead. My primary role - beyond selling the work - is to support the 4 men that now build it everyday.
Dave S
Dave once again. I truly love it. Keep it up.Best,
Mark
Measure it with a micrometer, mark it with chalk, cut it with an ax.
View Image
Hmmm. I live in hot humid Houston and have a leaded glass Mahogany entrance door that was purchased about 6 years ago. About a month ago I washed the outside of the door, let it dry, wiped it down with thinner and 0000 steel wool and brushed on a thin coat of Deft Polyeurthane with UV blockers. That was the original finish when installed by the company that made the door. No cracking, and hardly any fading in 6 years. The new coat of poly brought it back like new. The door is made of Honduras mahogany.
PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood
Polyurethane can be successful in some situations. As a maker of doors for everybody from churches to the idle rich, to the wannabe rich, I see a wide range of situations. Sometimes my finish info is maintained by the staff, and they meticulously keep things up. At the other end is the homeowners that overextended themselves to get into the house - with the doors- and after a little hiccup in their income, never quite keep things up. Then there are the folks that take a year to travel to Europe and beyond, with no one looking after such details.
Add to that the wide range of exposure situations, and it is very difficult to recommend one finish for all. I have poly on south facing doors that are 10' under a low porch - these doors never get direct sun on them. The finish is 15 years old and just now needs recoating - with no peeling. Poly on a south facing door - full exposure, will peel - often in the first summer.
We have a clearance guy nearby that gets on TV and screams about "giveaway prices on mahogany doors" (A shorea species, not Mahogany, doweled together with yellow glue, Chinese leaded glass in IG units with defective seals, and nailed frames) and folks poly his product with disastrous results. He tells 'em that is what maintenance is about, they go away disappointed, the doors look terrible, and the perception of wood doors goes down another notch or two.
While the Cetol satin is pretty flat, the gloss is looked at as plastic-y, so most people want satin. I agree it could be a bit glossier and more attractive. Epiphanes and the like are great finishes, but viewed as too glossy for this market. The old form vs function balance.
Dave S
Dave -
One side benefit of my buying that entrance door is that the company has let me haul off as much scraps as I can get in my pickup. Mostly prime Honduras Mahogany off cuts. Up to 3' long, 16" wide, and 3" thick. Heck of a deal! Occasionally a few other species of wood crop in. I've pretty much stocked all my kids houses with stuff made from these off-cuts.
http://www.doorsandaccessories.com/home.htm (our door was DA323107)
Talk about waste - they fill up a large dumpster about once a week with this stuff and have it hauled away. They also let me tour their construction facilities and I was greatly impressed by their quality of work.
My son's mahogany (?) door, purchased from the house builder, look like crap after 2 years.
PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood
Edited 5/25/2005 11:49 am ET by PlaneWood
Even with UV protection mahogany will "bleach "out in the sun. I have mahogany on a sailboat that is in the direct sun all the time; I use varnish twice a year(it nevers breaks) and it has still bleached out over the years. Cetol is goood ;it is used on a lot of boats by people who do not want to spend time varnishing and it lasts about one year in the direct sun. Then you just easily apply another coat; after about 5 years it may develop a black cast and you have to sand it off and start over. Cetol has one aspect that you should consider before using and that is that it has a slight yellow/orange color that puts some people off; I would try it on a scrap piece and see whether you like it. If I had a beautiful mahogany door, I would not want to put Cetol on it because of this; I would rather varnish more frequently. But if you don't want to varnish and don't mind the color, Cetol is an excellent product. If you want to varnish, I would suggest one of several marine varnishes ( Interlux Schooner 96, Epifanes, or Captains Spar Varnish). Another aspect to keep in mind: If you use varnish but let it go so it "breaks" and have to repair it, you will have to sand down to bare wood (which has not bleached out) and will be much darker ( like the original wood).
Among boaters, the issue is less maintenance/not as pretty (Cetol) or more maintenance/much prettier (varnish); most choose Cetol.
Sorry, this is more than you probably wanted to know.
First, most stains are not particularly lightfast and will fade if exposed to direct or even, indirect sunlight.
Second, as already stated, pure tung oil, or even the faux "tung oil finishes" have not UV protective qualities. Nor, of course, do they have much in the way of water or watervapor resistance. In other words, neither are a very good finish for an exterior door.
As also stated, polyurethane or urethane varnishs are not good when exposed to sunlight. Much better is a true marine exterior varnish purchased from a marine store. The big boxes do not carry effective "marine" finishes.
I am a proponent of using a "clear" paint. In other words the tint base used for oil based exterior dark colored paints. It contains all the UV inhibitors and mildewcides. The only thing it does not contain are the pigments that give it color. It dries as clear as an oil based varnish and lasts much longer. I finsish an exterior red oak door three years ago and the stained fiberglass door on my new home with this product. Both are holding up well.
Thanks to all,
We will get busy on refinishing the door. I'll let you know the results.
jack
Hello,
Check out the post # 23121.1 some of which I've cut and pasted below. It may be worth a try.
I found this article in about '98, lost it and just found it again. Some very interesting observations that I've never seen anywhere else:
In a recent post my friend, Steve, made reference to my tests of doggie sprinkling on exterior finishes. I figure after almost a year of testing it is time to post some interesting discoveries.
As a preface, allow me to set the stage. Almost daily there is a posting about clear, exterior finishes for doors, chairs, signs and such. Responses run the gamut from diehard marine finishes to apply a coat of primer and then paint. Each of these has a bit of a problem. Marine finishes are not always the easiest to find and it grieves me to think of a lovely oak, teak, mahogany, fir, redwood or similar nice wood door painted in mauve goop.
Bob from Fl inspired me with his continuing and accurate statements about the failings of a clear coat and the advantages of a good quality exterior paint. I decided after lots of reflection that he really was right but there was always the picture of mauve in my mind. Sooooooooo, how could one take advantage of his advice and yet capitalize on the beauty of a nice wood.
I began to reflect on the characteristics of paint. Now, comes the boredom.
There were several things I knew about paint. Exterior paints contain a mildewcide and a fungicide that a varnish does not. The best quality paints will contain a UV protectorant and trans-oxide pigments in very high percentages. Almost all paint is custom mixed by the store. The retailer maintains a large supply of base products that are used to achieve the desired color. There are generally 4 base products and the specific one for your paint is determined by your color choice. These base products are either named or numbered. They are named pastel, deep, tint and neutral. If numbered it is cleverly 1, 2, 3 and 4 with the exception of Olympic who numbers 1, 2, 3 and 5. Olympic is unaware that 4 comes before 5. Pastel and/or 1 is virtually a pure white and used for the lightest of colors. The others are slightly color altered from white and more translucent than pastel. These are used for succeedingly deeper colors. All of this comes to neutral, 4 and/or 5. These are clear and used for the darkest colors. In the can they are somewhat opaque but dry more or less clear.
Now comes the testing. I bought 4 oak exterior doors. Each door was given one coat of the same MinWax Stain. On 3 of the doors, I applied 2 coats of "base" to the 6 sides of each door (3 coats on the top and bottom edges). Each of these three doors had a different type of exterior neutral, 4 or 5 base. The fourth door was finished with a consumer "spar" varnish from my local friendly paint/hardware store. The bases for the 3 painted doors were an exterior semi-gloss acrylic, an exterior semi-gloss oilbased polyurethane floor paint and a semi-gloss oilbased trim and siding paint.
The doors were set up, slightly inclined, in mostly direct sunlight under a pecan tree in the backyard. My wife just loved that one. Daily, the sprinklers managed to hit the doors. The birds in the pecan tree used the doors for target practice. And, yes, the dogs did anoint the doors on a regular basis. My blonde Cocker, Zazu, was particularly enamored with the doors. Over the course of the test the doors experienced lots of Texas sunlight, rain and snow. The temperature went from below freezing to over 100. The advantage to the inclined position of the doors was the snow, ice, water from the sprinklers and the rain tended to collect in the raised panel areas. I feel these doors were subjected to far more severe environmental conditions than would be expected from normal use.
The results were interesting. The "spar" varnish looked fabulous but after about 2 weeks it began to develop small cracks. In rapid order the door began to turn black, started to mold and the smell was enough to knock a buzzard off of a manure wagon. The waterbased acrylic is milky in the can like a waterbased poly. It dried to a more or less water clear surface but was a bit cloudy. It tended to wash out the stain a bit. Over time it became cloudier and ultimately become almost white. But, it remained solid and protected the wood. The oil based bases are also a bit opaque in the can but dried to a clear finish that is almost identical to a spar varnish - they added an amber tone to the doors. Both the poly floor paint and the trim and siding paint remained "clear" over the entire test period.
The testing came to an end with a bit of encouragement. My wife said something clever like, "Get those damned doors out of the backyard?". She does not understand science. The floor poly had some minor checking and a thinned coat of the same base over the surface made that disappear. The door with the oilbased trim and siding paint was perfect other than it had lost a bit of the gloss.
So, I am with Bob - paint the door. My preference is the oilbased products. If you are predisposed to a waterbased use an acrylic rather than latex.
One thing you will find when you go out shopping for your product is a lack of knowledge on the part of the salesperson. Not many of these folk are aware that their neutral or 4 base will dry clear. If you want to have some fun, spring it on them. They will suggest you are full of Donkey Dust. Ask them to shake a can and put some on a stir stick. Dry it and voila, it is clear.
And here was one more testimonial to the procedure....
My recollection is that Jim made this post back in July, 2002 (at least that is when I saved it on my computer). Prior to the complete explaination he would post bits of the same information. About a year and a month or two before this post (spring of '01) I was talking with Jim while driving to Virginia to assist my brother-in-law with some maintenance on their log home. One of the tasks on the schedule was to refinish their south facing, no overhang front door...again! It was at that time that Jim informed me of his "test". A couple of days later the door was stripped, sanded, and "painted" with Olympic brand exterior oil-based paint base #5. By my count that's coming up on five years.
Just before making this post I called my brother-in-law to see how the door is doing. The report is that the door looks as good as it did after we refinished it back in '01—it shows no
signs of cracking, yellowing, or any of the other common traits of Helmsman Spar Urethane in a similar high sun exposure; the builder recomended finish of choice before Jim's advice.
I have used a couple of other brands and find that all perform pretty much the same so long as you get the paint base used to mix the darkest colors. Testing, however, is always appropriate. I can also sympathize with lack of help you have
received from your local S&W dealer. As soon as you explain to the typical paint store employee what you intend to do the reaction is generally the same—"Oh, that won't work..." On one of my let's-have-some-fun-with-this-guy visits to a local Benjamin Moore dealer last summer I explained the concept to the salesman behind the counter. He assured me with great certainty that I was completely wrong (I getting accostum to
hearing that) and that what I proposed wouldn't work. I asked him to open a can of the appropriate base and just stick a wooden stir stick into the paint. When he withdrew the stick
he showed me with great pride how cloudy and milky it was. I told him to set it aside and I would return later. When I did his response changed; "OK, its clear; but, it still won't work—if you
don't add the pigment the paint won't stick right" (his words).
So, off to Lowe's with you, get the #5 base and have some fun...
There are more old drunkards than old doctors. Ben Franklin
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