When refinishing a captain's chair, work outdoors, and place the chair on a piece of plastic. Apply a recommended stripper to a section of the chair, allow the stripper to remain on the wood for the recommended amount of time, and use a scraper and medium-grade steel wool to remove the existing finish. Repeat the process on each section of the chair, remove the stripping product, and sand the chair. Stain before applying two coats of polyurethane topcoat.
Use a scraper with rounded edges to prevent damaging the wood, and remove the existing stain by pressing forward with the scraper along the grain of the wood. Remove the stripper with the recommended product, which is typically turpentine, water or paint thinner, and allow the chair to dry.
Discard the plastic under the chair, and replace it with clean plastic after stripping the wood. Sand the chair with 220-grit sandpaper followed by 120-grit sandpaper to achieve a smooth, even surface. Clean the chair to remove wood particles and dust, and move the chair to a dust-free area to apply the stain.
Apply stain to the chair with a cloth, and wipe the stain with a second cloth immediately after applying it to achieve an even finish. After the stain is dry, apply a thin coat of polyurethane, wait for 12 to 24 hours, and apply a second coat of polyurethane.