What finish to use

[JR1]

I agree that, except for ease of application, the oil based exterior paints are better than the Water based (e.g. SW A100). Unfortunately; they are getting hard to get even where they are not restricted by VOC regulations. My local SW will special order their exterior oil base but only in 5 gallon or larger lots. They carry A100 routinely and it's almost as good.

[Howard Acheson]

Here are the details on using "clear paint".

OUOTE

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 poly "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 poly "spar" varnish initially 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 oil based poly floor paint and the oil based 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 oil based 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 fudge 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.

Jim Kull


END QUOTE

I used the clear paint on a number of exterior doors and number of years ago (maybe 8-10) and I looked at a couple of them the last time I went back to New York. They all looked virtually perfect.

Howie.....

[Randy C]

Finally went to SW to try to buy this paint. They are trying to sell me a lacquer which I know I don't want. Anything I can tell them to try to make sure I get the right product? Says the only thing they have that drys clear is the poly or sanding sealer which I know is not what I want.


They say none of their paints will dry clear??

Help!

[JR1]

SW A100 is what you want to get, it's an Acryilic and pretty wether resistant and durable. They do not carry oil based paints at least around here I haven't tried other paint stores, but the BORG Behr is not available in an oil base. I agree that the oil base is preferable but it's not available in a lot of areas. A100 is almost as good though again untinted. GF450 is still better though.

[JR1]

Jamestown also carries it. Epifanes Gloss Clear Varnish . Compared to a good untinted exterior paint (oil based or waterborne or to GF450) it's a non starter! Hugely more expensive and a major PITA to apply and maintain.

[Vijay]

Spar varnishes are not crated equal.  A good one like  Epifanes will last about 7 years with minor maintenance.   They are quite expensive and a PITA to use.  The good ones have UV inhibitors and will not yellow noticeably nor darken the wood much at all.  The BORG  "Spar Varnish" will last ~3 years at best and is a waste of money.

The best finishes for this are GF 450 and SW A100.   The 450 is clearer and a bit more durable.  Both are water borne and easy to use.  You can add  transtint to either to darken the wood.  Test before committing.  They will last ~9 years with minor maintenance.

Basically the top end waterborne exterior finishes have rendered Spar Varnish obsolete, even in marine applications.

I know this thread is over 2 years old. But looking for some clarification. The SW A100 is an exterior latex. Its base color is white, not clear.  If I wanted  a clear finish on an exterior finish it doesnt look like SW A 100 will work.  Sherwin Williams does have an exterior oil which comes is a deep base or ultradeep base. They also carry an all surface enamel oil base that is also available in deep base or ultradeep base.

Which of these products @JR1 , @Restorer,  is the right product for my need of  clear finish on exterior hardwood ?

Thanks 
Vijay

[jteneyck]

I know this thread is over 2 years old. But looking for some clarification. The SW A100 is an exterior latex. Its base color is white, not clear.  If I wanted  a clear finish on an exterior finish it doesnt look like SW A 100 will work.  Sherwin Williams does have an exterior oil which comes is a deep base or ultradeep base. They also carry an all surface enamel oil base that is also available in deep base or ultradeep base.

Which of these products @JR1 , @Restorer,  is the right product for my need of  clear finish on exterior hardwood ?

Thanks 
Vijay

This is an old posting indeed.  A couple of the participants no longer are.  But to respond to your comment about  A100, I can't remember which base you need, but I think you want Deep Base #4.  Whichever it is, it's white in the can but it dries clear, just like many other WB finishes.  You only want the base; don't let SW's add any colorants to it.  

John

[Bill Wilson]

Vijay, read Howard Acheson's post carefully.  His copy & paste of Jim Kull's story of using clear paint base is the foundation of practically everyone's knowledge on the topic.  That story has made the rounds of internet woodworking forums for years.  As others have commented, oil based paint is getting more difficult to find in some parts of the country, but the basic information and explanation of the clear paint base method is all in the Jim Kull story Howie posted.

Good luck.  Hope this helps.

[Vijay]

Fred, I think no one believes us about the exterior paint....but bears repeating:

DRIES CLEAR, less expensive, easier to apply (2-3 coats vs. many more), lasts longer, looks as good and easier to maintain.

For some reason I am no able to view posts after joe1086 post of 2016-02-11 including my own last post. I have sent a help note to the admins to see what might be happening with my account regarding this post.  But bizarre as it may sound as i am composing this reply I am able to see Bill Wison's post and JTeneyck's post from yesterday at the bottom of the composition window.  So thanks for the clarification.

[danceswithticks]

Fred, I think no one believes us about the exterior paint....but bears repeating:

DRIES CLEAR, less expensive, easier to apply (2-3 coats vs. many more), lasts longer, looks as good and easier to maintain.

Awesome, I believe you! This info is right on time for an Ipe bench I have in the works. I like the gray weathered look too but this wood has  beautiful color that I would like to try to preserve. I know it will become brown, but the grain pattern on this batch is nice as well. Thanks for the tip.