Issue: March 2011
Brightwork/Varnish



by Frank Lanier
photo by John A. Western

Here's the irony of brightwork--that is to say, all that lovely wood trim that makes boaters and boat-watchers go a little weak in the knees: Nearly every article on the subject (including this one, obviously) begins by saying that if your brightwork is teak, which it probably is, you can choose to do nothing to it at all, but rather allow it to age gracefully to a lovely silver gray. Hah, we say to ourselves, if I do that, every dockwalker from Chestertown to Rudee Inlet will look at my boat and its graceful silvery gray teak and think, "Gee that's a nice boat, but clearly not very well cared for." And because the people who write these articles (including me) know that's exactly what we're thinking, they proceed for the next several hundred words to lay out three or four options for not letting that happen. So, if you don't mind going gray, go ahead and get out there on the water. If, however, you're one of the rest of us, grab the Grecian Formula and read on. . . .

Brightwork beauty treatments fall into three general categories: oils, varnishes and synthetic wood finishes. The one you choose depends on the look you are after weighed against the amount of time and trouble you are willing to take. To help you make that decision, here are the good points and bad about each one.

 Oil
Let's begin with the oldest method and then work (and I do mean work) our way forward. Back when the whole boat was brightwork, in a manner of speaking, oil was the material of choice. These days, we use oil products such as Interlux Premium Teak Oil and Amazon's Golden Teak Oil to intensify the grain pattern and color of the wood, while maintaining its look and texture. Oil accomplishes this better than either varnish or synthetic coatings, but naturally it has its downside as well.

The "oil" in modern marine oil treatments is nearly always either tung oil or linseed oil. Linseed oil, which is manufactured from crushed flax seeds, is the cheaper of the two, but it can darken the wood significantly. Not a particularly good thing. Tung oil, which is derived by pressing the seeds of the Chinese tung tree, is more water resistant than linseed oil and doesn't darken the wood . . . or at least not at first. It is, however, more expensive. 

If you were to use either tung or linseed oil unmixed, you would find that they both would soon carbonize, turning the wood dark after only a couple of months in the sun. So oil treatment manufacturers mitigate this problem by adding other ingredients, such as resins, pigments, mildew inhibitors and UV filters. These additives vary from manufacturer to manufacturer. Additionally, some combinations are better suited to one kind of climate rather than another. What works for your teak in the blistering sun of a Chesapeake summer might yield disappointing results in the chilly mists of Maine. 

One of the big advantages of using oil treatments is that they are easy to apply. But, of course, the first step is to be sure your brightwork is clean, clean, clean. Yes, preparation is the cardinal rule of success. Oil treatments are applied with either a rag or paint brush--the product's directions will usually tell you its preferred method. In the beginning, the wood will soak up all the oil it can get, so the first coat is typically thinned by 20 to 30 percent with turpentine or mineral sprits. Then keep applying coats of oil until the wood can't take any more. Multiple coats also give a more uniform finish and greater longevity. By the second or third coat, oil will begin to pool in some areas. Wipe these areas with a cloth and continue brushing or wiping on the oil until the wood is fully saturated.

That was easy enough, but now here's the rub: Your new finish will last only three to six months before it needs to be retreated. And while oiling does restore some of the wood's natural oils, teak will last just as long without it. In fact, frequent oiling means more frequent scrubbing in preparation for the next oiling session, which can actually wear the wood away faster.

 Varnish    
When it comes to producing a finish that makes boaters ooh and aah, nothing beats varnish. Ah, varnish: deep, rich, elegant . . . agonizing. Yes, this most dazzling of wood finishes is also the most nit-picking, work-intensive, mythologized and prone to superstition, like plucking chickens at midnight. Entire books have been dedicated to the proposition of a flawless varnish finish. 

But such detail is hardly within the scope of this article, so while giving a nod to the fact that the price of beauty is a seemingly endless cycle of sanding and application in an effort to build up a sufficient number of coats--and we're talking maybe 15 to 20--let's stick to a discussion of the product itself. Varnish is a mixture of oils, solvents, thinners, dryers, resins and additives, all of which are manipulated by the manufacturer to produce characteristics such as finish (how shiny it is going to be), color and hardness. Of these, the most important, from a durability standpoint, are its ultraviolet stabilizers. Without it, varnish would absorb the UV energy, rather than diffusing or dispersing it, and begin to cloud and fade. Therefore, when you buy varnish for exterior brightwork, select one that is heavily fortified with UV inhibitors. 

The two most common types of varnish are natural resin varnish and oil-modified polyurethane varnish. Higher quality natural resin varnishes use Chinese tung oil, while lesser grade varnishes use oils such as linseed or even soybean oil. The resin in natural resin varnishes are typically derived from tree stumps, while phenolic resins used in modified polyurethane varnishes come mainly from crude oil.

Natural oil varnishes (Epifanes Clear Varnish, Captain's, Flagship and Interlux Schooner, for example) work well for both interior or exterior uses and provide that golden look that many boaters love. These have good water resistance, moderate hardness and superior flexibility--which allows them to cope with the minute movements wood experiences with changes in temperature and humidity.

Oil-modified polyurethanes (Interlux Goldspar 95 and Sikkens Clear Varnish, for example) come in both one and two-part coatings. They tend to be clearer (allowing the color of the wood to shine through), provide faster drying times, a harder finish and better water resistance, all of which means better durability in extreme climates.

Varnish certainly has the longest durability of our three choices, though, of course, the type of varnish used, number of coats, the weather and how many chickens you've plucked at midnight all must be taken into account. 

 Synthetic Wood Finishes
We come now to the third--and most modern--category of brightwork treatments. These are the synthetic wood finishes such as Cetol or Amazon Teak Lustre and represent a variety of compromise because they produce a pretty good imitation of varnish yet are easy to apply, fairly low maintenance and are reasonably durable. They also work well on oily woods like teak. While synthetic wood finishes or sealers don't replenish the wood's natural oils, they do seal them in, while sealing out moisture, dirt and other contaminates. Some of these produce a clear finish, while others, such as some of the Cetol products, produce an orange-brown color because of the UV inhibitors (which are iron oxide pigments in the case of Cetol).

Sealers can be applied directly over clean or sanded wood. Since they don't add oil, however, you may want to clean, bleach, then oil the wood first to prevent a spotty appearance.  If you decide to oil first, wait a couple of weeks to allow resins in the oil to dry completely. Then wash the wood and give it a quick wipe down with a rag soaked in acetone to ensure that the surface is oil free and ready for the sealer. Rapid drying times and no sanding between coats means that layers can be built up quickly. And there's no need to worry about your brushing technique. Just apply the sealer until the wood shows a uniform surface, then wipe away any excess. Each manufacturer will provide instructions on maintenance, but as a general rule you'll want to wash the wood and apply a new coat of sealer every three to six months, depending on your location.

So there you have it, brightwork with a mirror-like finish to brightwork in a gracefully aging gray . . . and everything in between. The choice is yours.