penetrating oil or varnish
Posted by: pblanc on Nov-02-12 10:08 PM (EST)
Some prefer a bright finish (polyurethane or varnish) on wood gunwales and it does have more staying power than penetrating oil, but it tends to get scratched.
I have used Watco regular penetrating oil, Watco exterior penetrating oil, Watco teak oil, Deks Olje (a Danish oil that is hard to find these days), Gunwale Guard, and Formby's Tung Oil finish. They all work pretty well but I wouldn't suggest Gunwale Guard as it tends to get gummy.
Unless your boat is going to stay outside all the time exposed to sunlight you don't need to get the exterior formulation of Watco oil. The regular works just fine.
Some folks use plain boiled linseed oil, but I have found that straight boiled linseed oil tends to mildew. Some people swear by a "home brew" that usually is a concoction of boiled linseed oil with vinegar and some type of organic solvent like turpentine or even kerosene mixed in but I haven't used them. Some folks also mix a little varnish in with their Watco oil. If you want to darken the wood a little, you can mix a small amount of walnut or cherry stain into your oil.
The Watco Teak oil seems to have a little better staying power than the regular and it tends to darken light colored ash a bit more than regular Watco oil which you may or may not like. It is also more expensive than regular Watco oil.
People claim that Formby's Tung Oil finish has little actual tung oil in it. I really don't care as it gives a nice sheen and is fairly easy to apply.
Most hardware or box stores will have Watco oil and probably Watco Teak oil and Formby's as well.
I usually apply the Watco products with a paint brush and then wipe off the excess after it soaks in. The Formby's is applied with a cloth and rubbed in sort of like a liquid wax.
I think a nice sheen is largely a product of repeated application and hand rubbing as hand warmth tends to allow the oil to penetrate better.