How to Polish a Polyurethane Topcoat

Polyurethane topcoats allow wood surfaces to shine.

A polyurethane coat is applied to a wooden surface to highlight the beauty of the grain pattern and to provide a lasting, protective finish. Commonly used on bars, bar stools, tabletops, hardwood flooring and large pieces of wooden artwork, polyurethane protects wood from spills, stains and premature wear. Once applied, the topcoat can be polished regularly to produce mirror-like results.

Things You'll Need

• Fine-grit sandpaper (100-grit to 120-grit)
• Solvent
• Soft cloths
• Orbital sander
• Felt polishing pad
• Wood-polishing compound
• Polishing cloth

Instructions

1. Remove any imperfections in the polyurethane topcoat, such as air bubbles or ripples, with a wet piece of fine-grit sandpaper (100-grit to 120-grit). Ensure that the sandpaper and the surface of the wooden object are kept wet at all times to avoid scratching or gouging.

2. Clean the area to be polished with a light solvent--such as mineral spirits or isopropyl alcohol--and a soft cloth. This removes any residue or dirt that may hamper the polishing process.

3. Attach a felt polishing pad to your orbital sander, and plug it into a power source.

4. Apply a small amount of wood-polishing compound to the polishing pad, and start the sander at a slow speed.

5. Move the pad across the topcoat, applying firm, even pressure. For mirror-like results, set the sander to medium speed. Re-apply polishing compound to the pad as needed.

6. Allow the polish to dry for the time suggested on the container.

7. Buff off the compound with a clean polishing cloth. Wipe the area clean of any leftover polishing compound using a damp cloth.

Tips & Warnings

• Operating instructions vary among different orbital sanders. Refer to the owners manual of your specific sander to achieve the best results.

• All of the supplies required for this project may be found at your local hardware store or home improvement retailer.

• Do not allow children or pets near your work area.

• Use caution when handling the orbital sander. The disc rotates at a very high speed and may be dangerous if mishandled.

References

• Woodweb: Polishing Polyurethane to a High Gloss
• The Family Handyman: How to Apply Urethane