Finish longevity

[T.R.MacMunn]

I'm sure you'll all heard me "dissing" natural exterior finishes, & probably figure I'm full of ****. Well .... here's proof that just maybe I'm not

This sign has been out in the weather since May 2001 & was brought in for a re-fresh. It's not the original owner, so it';s not warranty. 3" thick western redcedar.

The outer border was done with Sikkens Cetol .... supposedly the best of the best natural finishes then, & some say , still. The only place where ANY survived, is on the edges, where the sign was tight to the posts.

All the raised areas were done in leaded 1-shot lettering enamel, & still look pretty good.. However, the EPA started messing with paint ingredients, leading to lead & even some pigments being banned, so after 2005, it went for a crap. The fish is faded, but that's because the paint had to be thinned out for blending, etc..

The background? .... well, this is one of the first signs I did with acrylic paints, rather than oil-based stains. Other than the burgundy panel at the bottom, there is little fading on the other colours, & there's very little peeling ....just in one small area on the north side where the grain would let water lay.

I rest my case, in favour of good 100% acrylic house paints.

[Jimwill52]

I'm sold, acrylics for me. By the way, how are you doing?

[The real JP]

Looks pretty good in the pic.

Wonder why my garden shed flakes paint after 2 years.....

[T.R.MacMunn]

I'm doing great, Jim...... just can't get US medical insurance for 6 more months.

JP ....there may be a lot of reasons for flaking..... the quality of the paint, the quality of the primer, how dry the undercoat is , etc.....
One thing to remember with acrylic paints is that they take up to 30 days to completely dry, although they'll feel dry to the touch in just a couple of hours or less. I will wait 24 hours when the humidity is low, & 48 hours in the summer, when the humidity is really high & rarely have an issue.
Latex paints were notorious for peeling .... acrylics, not so much. Acrylics allow the wood to breathe ( moisture migration) . Generally, if you can't find "100% Acrylic" on the can, it's not good paint.

[John B]

TR

Sikkens Cetol is a great product, but it's not without its caveats.

1) It needs a "maintenance coat" pretty much annually (at least outdoors in the coastal sunshine where my boat resides)

2) You need to stay away from the "clear" as it has no UV inhibitors. If you want it "shinier" you can add a clear gloss on top of the earlier coats.

3) About 5 initial coats is a good start. This is going to pretty much obscure any "light grained" wood grain and leave a distinctly orange finish that gets darker with every coat. If this isn't acceptable, then paint it instead (with acrylic). If you're not liking the way it looks (more and more) with every coat, don't skip the remaining coats or you'll end up with a weak finish.

4) After each coat dries, you scuff it lightly with a green scrubby pad, wipe it clean and re-coat. This is the same process for the maintenance coats. The finish is self-leveling if applied with a wet edge.

5) Most importantly...it's designed to "encapsulate" the piece that's being protected...which pretty much means that you need to cover all sides of the same piece with the same product. If you don't, then ANY water intrusion (such as where you switched from Cetol to Acrylic or an unfinished "back side") is going to cause the wood to swell and the finish to lift.

6) I've had the best luck by cutting the first coat 50% with mineral spirits to get a good absorption (rather than having the finish "sit on top" of the wood as it does otherwise. I start with a very finely sanded bare wood finish which is made even smoother with a cabinet scraper before finishing.

7) Avoid the temptation to use foam brushes...while it looks better (immediately), the coats are thinner and you need some "build".

8) With annual maintenance coats (quick and easy), I kept a beautiful finish on my exposed teak breakwater rail on my sailboat for ten years until I let it "go too long" and got some blistering. It sits in a saltwater slip on Corpus Christi Bay in a very inhospitable environment.

All that being said, most people are going to "not do this". What you've shown above is the result.

[T.R.MacMunn]

Well John, this was coated with one coat of Cetol 1, & 2 coats of Cetol 23 ... exactly as recommended by Sikkens back then. Most failed within 5 years. None were "clear". I don't think I'd have sold anything back then had I told my customers that they'd need to do a maintenance coat every year, & I certainly wouldn't be doing it .... I sell signs hundreds of miles from here. I refinished many under warranty before I ditched the stuff.

The coat of Cetol 1 was continuous .... the Cetol 23 was not. The Cetol 1 soaked into the cedar quite well.

I like seeing natural wood colour as much as the next guy, but since I started painting in my woodgrains about 15 years ago, I've had no issues. So, I don't know how you can call a finish that lasts one year "a great product". But, in all fairness, some signs I did with it in the 90's do still look good ....one is indoors & the others are under a roof, & far enough from a road to not get any salt-spray.

[T.R.MacMunn]

Repaired, refurbished & refinished .........
The woodgrain you see is acrylic paint, which will long outlast any "natural" finish without maintenance coats.

[neal_meyers_jr]

Very nice.

[Jim Becker]

Excellent refresh on that one!

[guitarwes]

TR, can you give some tips on thinning this paint for airbrushing? Thanks much.