Osmo Oil: Durable, Easy to Use, and Nontoxic
Marcus Soto's technique starts with a slurry of Polyx-Oil sanding in to fill the grain. After that he applies it like a traditional oil finish and buffs it out.
My business partner and I run a sustainable lumber company and make custom furniture from these trees (see my trestle table on pp. 30–37). In the spirit of how we harvest and use the wood, we want our finish to be easy to use, durable, non-toxic, and easy on the environment. Osmo Polyx-Oil is all those things. Made from natural vegetable oils and waxes, it does not off-gas or smell bad. It’s durable, easy to apply, and easy to repair. The secret to success with this oil is filling the pores first.
Start the surface prep by sanding up to at least 220 grit. At 180 grit, I raise the grain with a damp cloth and then continue sanding. Next, make a slurry to be used as the filler. Add a thin coat of Polyx-Oil with a cotton rag. Then take wet-or-dry sandpaper of 220 or 320 grit and sand the finish into the wood. The slurry should have a puttylike consistency. After you produce the slurry, work it into the grain. Ball up a rag as if you were doing a French polish. Start at one end, working your way down in overlapping circles. Let the filler dry overnight, then sand it down with 150-grit paper. If there is any open grain, sand to 220 grit and repeat the entire process until there is no more open grain; twice is usually enough. Sand to the finished grit and you are ready to add the final coats of Polyx-Oil.
Polyx-Oil is applied like a traditional oil finish: Put it on, let it penetrate, and wipe it off. Allow at least eight hours for the finish to dry. For a tabletop I usually add three coats. On bases, I add two coats following the same process. Between coats I scuff-sand with a very fine abrasive pad. You can also use very fine sandpaper, 320 grit or above. After the finish has cured, I use a clean cloth to give it a thorough buffing out.
Fill the Grain
Filling open grain with the slurry will provide added protection by decreasing the chances of moisture building up in any of the open capillaries of the wood. This makes the finish suitable for tabletops.
Then Build the Finish
Marcus Soto is design and production partner at New York Heartwoods in Kingston, N.Y., and owner of Sojen Design.
From Fine Woodworking #262
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