There are many different finishes that woodworkers use in order to strengthen and protect wood. Some finishes act to waterproof the wood while preserving the natural grain, and others bind to the natural fibres in order to strengthen the overall structure. Application of these techniques extend from small balsa wood projects to patio deck protection. Choosing a method depends on the job. The most common tasks involve rot repair with wood hardener, and waterproofing and strengthening with epoxy.
Locate any rotten sections or loose knots in the wood. Drill or scrape out any rot until healthy wood shows at the surface. Sand the entire surface to a finished smoothness.
Treat any area that contains or has contained rot with liquid wood hardener according to the product instructions. This stops future rotting and strengthens damage. Allow the treated areas to dry fully.
Fill any gouges, holes or knot gaps with epoxy using a putty knife. Allow the epoxy to cure according to the drying time on the label. Scrape off any excess with the putty knife.
Fill a brush or a rag with the wood epoxy and work it into the entire surface of the wood grain. Follow any additional instructions on the epoxy cans. Allow the epoxy to completely cure overnight or longer.
Scrape off any raised epoxy and finish sand the entire surface. Buff and polish to the desired texture.
Wear all proper safety equipment and work in a well-ventilated area. Read all safety instructions on the products.