I have no position on which of these "oils" produce better results for different users on different woods.
I do know that neither Watco nor Deks Olje is an oil per se, but both rather are mixtures of linseed oil and different combinations of different forms of petroleum naphtha. I don't see how the oil of either could "penetrate" more than the other, since the oil in both cases is linseed oil.
More generally, I don't really understand why why any of these oil mixtures are different from varnishes, broadly defined, and indeed Deks 2 is marketed as a "high gloss oil varnish". Perhaps the primary difference is the amount of linseed oil in the formulation and the cure speeds of the drier and solvent chemicals.
I suspect the finish of each of these products is determined simply by how many multiple layers are ultimately built up on top of each other, and how hard they dry, so as to enhance protection, gloss and lasting ability -- the same way that is done with products labeled simply as varnishes.
I note that the Deks technical data specify that the product has been formulated for "thick, dense, oily and hard to impregnate woods" such as teak, mahogany, oak, and a bunch of tropical exotics I have never heard of. From all this, it seems reasonable that Deks, if applied properly, would be a very good finish for mahogany woodwork on a canoe.
I don't know if ash, pine and spruce, which are common gunnel materials on flat water canoes, fall into Deks' target of thick, dense, oily and hard to impregnate woods. However, spar varnish has worked well for me on these wood gunnels, giving many years of lasting gloss. Watco also does a very nice job, especially if rubbed properly to gloss, but it has to be applied much more frequently than spar varnish and probably Deks varnish.
Touring Kayak Paddles
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