How to Apply Oil-Based Polyurethane

Oil-based polyurethane protects wood furniture as well as enhances the natural wood appearance. The finish is clear and shows off the grain of the wood. To apply oil-based polyurethane to your furniture, follow the directions in this step-by-step guide.

What You Will Need:

  • Oil-based polyurethane
  • Sandpaper (100, 150 and 220 grits)
  • Wet/dry sandpaper (400 grit)
  • Mineral spirits
  • Clean, lint-free cloths
  • Tack cloth
  • Sanding block
  • Wet/dry vacuum
  • Breathing mask
  • Paint brush
  • Razor blade
  • Automotive rubbing compound
  • Automotive polishing compound
  • Step 1 - Sand the Wood Surface

    Sand the surface of the furniture until it is smooth.

    Step 2 - Clean and Vacuum the Dust

    Use a cloth and shop vac to remove dust from the furniture.

    Step 3 - Seal the Surface

    Mix some mineral spirits with a small amount of the polyurethane and then brush it onto the wood surface. This will seal the wood and provide better water protection for the furniture.

    Step 4 - Apply the First Coat

    After the sealer dries, brush on the first coat of oil-based polyurethane. When applying the finish, use long and even brush strokes.

    Step 5 - Sand Again

    After the first coat dries, sand the entire surface of the wood again. Start with 100-grit sandpaper and work your way up to 220- (or higher-) grit paper.

    Step 5 - Apply More Coats

    Apply two to three more coats of polyurethane. Sand in between coats with higher grits of sandpaper, and wet-sand with 400- (or higher-) grit sandpaper before you apply the final coat. Use the razor blade to gently scrape away drops of polyurethane. Carefully apply the last coat of oil-based polyurethane. Lightly wet-sand again.

    Step 6 - Clean Up and Polish

    Use rubbing compound and polishing compound to polish and shine the furniture.