Friday, December 28, 2018
The Ten Commandments of Varnishing Brightwork On Yachts
Some do-it-yourselfers have figured out a thing or two about varnishing through trial-and-error and consultation of whoever has the best-looking brightwork on the dock (probably done by a hired pro), but it's the person with years of on-the-job experience who can give you the best information.
What he tells you may not agree with what the varnisher on the next dock tells you, but judge and compare their words by the appearance of their work. Whose looks best?
Thus sayeth Vicente:
1. Perform your due diligence and research the subject. Consult the writings of professionals.
2. Determine what tools and materials you'll need, and gather them in advance.
3. If it's a refinish job, use a heat gun and a wooden-handled scraper to remove old varnish.
4. Very carefully use paint and varnish chemical stripper to remove old varnish caught in the grain of the wood (keep a water hose with spray nozzle handy).
5. Treat the wood with a 10% dilute solution (1 part to 9 parts water) of teak cleaner and then of brightener to even the color, remove stains, and kill mildew and fungus.
6. Use hard blocks (you can make your own from a smooth two-by-four) in 16-inch and 8-inch lengths to level the hills and valleys with the coarser grits of sandpaper on toerails and caprails, or broad expanses of wood like a hatch cover. Use a 6-in soft rubber block for curved surfaces and for the final fine-grit sanding.
7. Vacuum the whole boat, including the stripped and sanded wood, to remove dust. Wipe wood with denatured alcohol or mineral spirits. After the bare wood is sealed, hose down and chamois the whole boat between varnishing sessions.
8. Tape off the edges of wood and around metal fittings such as stanchion plates with 1-inch wide quality painter's tape with one-week rating for outdoor use.
9. Apply twelve coats of your choice of spar varnish as per my instructions below.
10. Remove tape, clean up varnish drips or runs on gel-coat and decks, and wipe off tape residue. It's not a professional-quality job unless you do this.
You can learn a lot too by researching the subject online and by reading Rebecca Wittman's superb book, Brightwork: The Art of Finishing Wood. It's a literate and entertaining coffee table book as much as it is a how-to manual, and it's full of photographs of gorgeous brightwork on some magnificent yachts.
I wish I'd read it before I invested so much blood, sweat, and tears in learning my trade. Fortunately, the hard-won knowledge gained by years of experimenting was very close to Wittman's own advice.
Be forewarned, though, if you haven't already discovered this: there's a lot of conflicting information out there, and a fair amount of it was written by people who've never laid varnish in their lives.
Thin or Not?
Bear in mind that whatever advice I offer here is my opinion, based on my experience. If you disagree, that's fair, but I'm not writing here to give equal time to opposing points of view, which may be just as valid, by your lights.
A common mistake novices make is not thinning whatever varnish they're using. Often, the instructions on the can will tell you not to thin, in bold-faced letters, or to thin no more than 5%. Rest assured that it is a manufacturer's disclaimer, intended to prevent the user from altering the chemistry of the product, which, of course, they cannot be liable for.
It's almost impossible to get a level mirror-like finish with no brushmarks or lap lines, without thinning. Contrary to label instructions, I thin varnish 30%, even 40% of volume, for every coat, according to weather conditions. Be forewarned, this will make a thin, runny mix, but it will dry fast, and that's how you can do multiple coats in a day.
Another reason to thin this much is that in a subtropical climate like Florida's, varnishing in the sun is unavoidable for most – again, contrary to manufacturers' disclaimers.
If you apply unthinned varnish to teak in the hot sun (remember, it can be 90° Fahrenheit or 32° C by 9 o'clock in the morning in Florida), the varnish will wrinkle, or 'alligator', disastrously, because the top of the liquid will dry faster than underneath, and shrivel. Thinning prevents this action, but it's best to avoid laying varnish from two hours before noon till two hours after it in the summer, unless you're in Sweden.
I've done some varnishing in one of the big sheds at a yard, and there are advantages to that – you don't have to worry about wind, sun, or rain. But I'd rather not work on a boat indoors. I do this kind of work because I love boats kept Bristol fashion, the sea, and fresh air.
It is good practice to use the maker's recommended thinner, or 'reducer', and with two-part finishes, it's critical to do so. In that case I would use the proportion called for in the instructions. However, with traditional spar varnishes, for everything from Schooner's to Epifanes, I've found that plain old paint thinner works fine with every one I've tried.
Be sure to use a product labeled 'paint thinner', rather than 'mineral spirits', as simple paint thinner is not as highly refined as spirits, and will dry slower, which is the whole point of using a thinner (unless it's cooler weather, and you want it to dry faster).
Since waterways act as wind tunnels, there's almost always some wind at a marina. The windier it is, the more thinner I add, and if it's blowing fifteen knots or more, I may have to add a couple capfuls of thinner every fifteen minutes or so. Wind and sun work against the varnisher, though a light breeze is good to keep the no-see-ums at bay.
Here in Florida, when the seabreeze picks up in early afternoon, the moisture in the sea-air may cause the varnish to 'stand up', and not level as well, or even to form little air bubbles. I then add an extra capful of thinner to my varnish pot to compensate.
Bubbling in a dried finish may be caused by residual moisture trapped in the wood. That's another benefit of using a heat gun to strip old finishes – the heat helps drive such moisture out of the wood.
Some people have the misconception that all varnishes dry slowly, which is a holdover from the days before metallic salts were added as driers. A varnish that contains a high proportion of tung oil, like Epifanes or Flagship, will dry slower than others, but this should only be of concern if the ambient temperature is less than 70° Fahrenheit ( 21° C), and then you shouldn't apply it too late in the day.
I'm no fan of water-based finishes. They may have some ecological advantages, but they aren't as durable as oil-based varnishes. Like polyurethane, they're quite sensitive to atmospheric humidity, and will 'blush', or cloud if humidity is high. Even oil-based varnishes will do this if applied too late in the day and the dew hits the finish.
Also, remember that humidity is highest just before the dew point is reached when the air is saturated in the evening (usually right before sundown) or the early morning. Humidity can be a factor even indoors in a non-climate-controlled environment like a garage or workshop.
Finally, geographical location does make a difference in application methods – most of my varnishing experience has been in Florida, so keep that in mind and adjust your practices according to local conditions.
Varnish or Cetol?
Some of the traditionalists may regard me as a heretic, because I use throw-away foam brushes, rather than the traditionally-approved, expensive "badger" hair brushes.
To those purists I reply that the famous Rebecca Wittman, who wrote the beautifully illustrated book, Brightwork: The Art of Finishing Wood, is on my side. She and I prefer the Jen-Poly brand of foam brushes. And it doesn't really matter which brand of varnish you buy, as long as it's a reputable one, with adequate UV filters.
Some of the better-known spar varnishes are Schooner's (made by Interlux, now owned by Akzo), Epifanes (Dutch-made), Flagship (made by Z-Spar, their top-of the line), Captain's (also made by Z-spar), and Awlspar (made by Akzo Nobel, the same company that makes Sikkens Cetol products). All of these are quality varnishes, with sufficient ultraviolet light protection, although they have different handling characteristics.
I would avoid the house brands of marine store chains – they tend to be of inferior quality, in my opinion, having observed the experiences of certain do-it-yourselfers who wanted to save a few bucks. Just remember that the real cost of any refinishing project is in the hours spent in labor, not in a few extra dollars paid for a superior product. Besides, after investing all that time and energy, don't you want the result of all your efforts to last as long as possible, looking its best?
I personally prefer Awlspar for buildup coats, because it's a quick drying, high-solids varnish with excellent handling qualities, and best of all, you have a 24 hour time window to apply successive coats without sanding in between. Professionals call it "hot-coating", and it will save you countless hours of unnecessary labor. I routinely apply four coats outdoors on a spring or fall day here in Florida.
Now for the greatest heresy of all: mention the word "Cetol" to many boaters, especially the traditionalists, and you'll be received with a look of disgust or horror. This is because they've only seen the misbegotten-from-hell results of an amateur job done by someone who didn't know what he was doing.
Granted, I've seen many a Cetol job that looks like someone used a dark, opaque shoe polish to finish his teak. I assure you that with a proper understanding of its handling, even the novice varnisher can produce a top quality finish with a two-part Cetol system, that looks almost as good as the best varnish job.
I use traditional spar varnish on most of my jobs, but I finish them off with two top coats of Sikkens Cetol Marine Gloss. Confusion enters the scene when you talk about Cetol, because most people seem not to understand that it's really a two-part system.
I would say that Sikkens is remiss for not informing its customers, via the application information on the can, that if you're going for a straight Cetol job, it's best to use three coats of the base pigmented product (Cetol Marine Natural Teak) and to top it off with multiple coats of the clear gloss second part of the system.
Sikkens (a division of Akzo Nobel) will never tell you that the gloss version of Cetol can be applied over spar varnish, understandably, because of theoretical possible incompatibility problems, thus the disclaimers you'll read on the can.
Rebecca Wittman has wisely informed us that any products which use the same solvents in their formulation are compatible, and may safely be used in lieu of one another, in correct sequence. I've found this to be true in my experience, and now routinely top off all my varnish jobs with two coats of Cetol Gloss, which lasts longer and keeps its glossiness longer than any spar varnish on the market.
As I said previously, I build up eight to ten coats of Awlspar, and then finish with two coats of Cetol gloss. This twelve coat brightwork system will last a year before needing maintenance coats, even in the harsh solar conditions of South Florida.
How to Avoid Brightwork Hell
There's a lot of contradictory advice out there about varnishing versus oiling teak. I chuckle when I dip into the forum discussions at some sites. Even pro woodworkers are telling people teak should never be varnished.
Nonsense.
Haven't they ever seen a fine yacht, like a Hinckley B-40 yawl, for example, with miles of gorgeous varnished teak brightwork? How can anyone say that?
I take it personally, because I've been varnishing teak on various fine yachts for nearly thirty years. Once a guy approached me as I was in mid-brushstroke varnishing the toe rails on a Sou'wester 42, and berated me for telling his uncle how to varnish teak, because everybody "knows" you can't varnish teak.
As I said, I was varnishing teak when he launched into his tirade! It's what I do for a living, every workday.
The varnish vs. teak oil debate
And then there's the perennial debate about varnish versus teak oil. Unless your vessel resides in a far northern latitude like Scandinavia's, you'd better forget about using teak oil on your exterior teak.
If you think varnish is high maintenance, just try using teak oil. You will be quickly disabused of the idea that it's less work, and besides the hassle of continual re-application, it's a magnet for pollutants and dirt. It's difficult to keep an exterior oil finish looking presentable, and people who say teak oil lasts for months or even a year outside are sadly mistaken.
Tips for varnishing teak
I've always advised prospective customers that the secret of maintaining beautiful varnish is to apply enough of it from the get-go, meaning at least eight coats of varnish, with two top coats of Cetol Gloss (clear) on bare wood in Maine, and at least ten coats of varnish, with two top coats of Cetol Gloss in Florida. I also tell them to ignore anyone who insists that the teak needs two maintenance coats every three or four months. That's nonsense.
If I had to recoat my customers' varnish that often, I wouldn't have any customers. There's no reason a properly applied finish shouldn't last a year, even in south Florida, as long as it's not abused, and kept clean. Letting crud build up on it by not bathing it frequently, at least once a week, can compromise its integrity, no surprise there.
Once I've done the initial ten or twelve build-up coats the first year, I do two annual maintenance coats of Cetol Gloss over the varnish thereafter. I've had people challenge me on this, expressing disbelief, but my customers will verify it.
Even with the best application of the best UV-resistant products, the wood will show color changes over time (usually lighter, not darker—sunlight bleaches wood, no matter what some "experts" say), and will lose some of the clarity and life of its grain. Even so, a properly maintained brightwork finish can look very good for 6-8 years, without stripping and revarnishing.