Clear Finishing of Outdoor Wood

For many years builders of wooden boats have used a combination of two-part epoxy resins and marine spar varnishes to make "furniture quality" clear-finished watercraft. That these boats look good after several years of outdoor exposure is testament to the synergistic effect of using these products together. The same techniques can be used to protect many wood projects, allowing them to be left outdoors uncovered for months at a time without fear of the finish failing, the wood warping, splitting, or discoloring, and joints coming apart.

Clear Coat™ and SilverTip Epoxy offer excellent barriers to both liquid and moisture vapor.  They are easy to apply with a brush or a roller, and will cure to a tough, clear, high-gloss film which will waterproof the wood. But the epoxy film does not protect the wood from sunlight.  In addition, exposure to the sun will dull, darken, and eventually degrade the epoxy coating underneath.  To avoid ultraviolet light damage, and offer complete protection to the wood, overcoat the epoxy with either one of System Three's clear finishes. 

System Three Marine Spar Varnish™, a high gloss/silky satin, high-solids, "oil-base" finish, is designed for marine and exterior wood surfaces.  Our Spar Varnish is a polyurethane formulation, and contains ultraviolet light absorbers which will keep wood looking beautiful even with constant exposure to sunlight. It was formulated specifically to cure properly over System Three epoxy resin products.

System Three WR-LPU™ Marine Topcoat, a two-part, waterborne, polyurethane enamel, will provide performance equal to its solvent-borne counterparts. Like our Spar Varnish, it contains UV-absorbers.  WR-LPU topcoat comes in clear gloss and satin, is extremely weatherable and abrasion-resistant, and will retain its properties for long periods in a variety of environments.  

Other items you may need:

  • Rags
  • Sandpaper

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