Should Use Sanding Sealer Before Polyurethane
When it comes to applying polyurethane to wood surfaces, many people often wonder whether they should use a sanding sealer before applying the polyurethane. The answer is a resounding yes. Sanding sealer plays a crucial role in ensuring that the polyurethane adheres properly to the wood and provides a durable, long-lasting finish. In this article, we will discuss the importance of using sanding sealer before polyurethane and the benefits it offers.
Understanding Sanding Sealer
Sanding sealer is a type of sealant that is applied to wood surfaces before painting or finishing. It serves several purposes, including filling in small cracks and pores in the wood, providing a barrier against moisture, and improving the adhesion of the finish to the wood. The primary ingredient in sanding sealers is usually shellac, which is a natural resin derived from the lac bug.
Benefits of Using Sanding Sealer Before Polyurethane
1. Enhanced Adhesion: One of the main reasons to use sanding sealer before polyurethane is to improve adhesion. Sanding sealer fills in the wood’s pores and creates a smooth, even surface, allowing the polyurethane to bond more effectively with the wood fibers. This results in a more durable finish that is less prone to peeling or flaking.
2. Moisture Protection: Wood is a porous material that absorbs moisture, which can lead to swelling, warping, and other issues. Sanding sealer forms a protective barrier that helps to prevent moisture from seeping into the wood, thereby reducing the risk of damage and extending the life of the finish.
3. Improved Sanding Surface: Sanding sealer makes the wood surface more uniform and easier to sand. This allows for a more consistent finish and reduces the amount of sanding required before applying the polyurethane. In turn, this saves time and effort during the finishing process.
4. Reduced Odor: Sanding sealers often have a lower odor compared to polyurethane, making the application process more pleasant for the user. Additionally, the sealant can help to minimize the odor of the polyurethane itself, as it acts as a barrier between the wood and the finish.
How to Apply Sanding Sealer
To apply sanding sealer, follow these steps:
1. Clean the wood surface thoroughly to remove any dirt, dust, or debris.
2. Sand the wood lightly to create a smooth, even surface. Be sure to sand in the direction of the wood grain.
3. Apply the sanding sealer using a brush, roller, or sprayer. Follow the manufacturer’s instructions for the recommended thickness and drying time.
4. Allow the sanding sealer to dry completely before sanding it lightly with fine-grit sandpaper to remove any imperfections.
5. Apply the polyurethane as instructed, taking care to maintain a consistent coat and avoid drips or runs.
In conclusion, using sanding sealer before applying polyurethane is an essential step in achieving a durable, long-lasting finish on wood surfaces. By filling in pores, improving adhesion, and providing moisture protection, sanding sealer ensures that your polyurethane finish will look great and last for years to come.
