Preventing Bubbles In Urethane Floor Vinish

Brush out bubbles in a fresh polyurethane finish.

Preventing bubbles in urethane floor vinish.

Heavy coats of paint levels as it dries flattens out to hide brush marks and minor defects. Very smooth surface preparation. There are several things that can cause bubbles in the finish. Stir the contents instead with a paint stick in a gentle swirling motion.

Applying polyurethane and most other finishes in heavy coats creates bubbles puddles and runs and becomes a defect in and of itself. I had tried every option i could think of. Stain that has not dried before the first coat of finish can cause bubbles. Resist the temptation to shake the polyurethane prior to use.

When the finish hardens you have to sand them out and apply a new finish. I was applying semi gloss finish polyurethane on an oil stained birch tabletop. Finish brushes delicately lay on a thin clear coat to accentuate the surface below. I had similar problems with very fine bubbles in topcoat.

However if you re not careful small air bubbles can mar the beauty of the finish permanently. The only remedy is to sand out the bubbles and apply another coat of finish more. By the way water. Some brands of finish are known to bubble more than other brands.

This happens to floor finishers who drag the finish applicator aggressively and then must stay off the floor until the finish dries. Sanding between coats with very fine grit paper 220 and finer. Stir the can prior to use and take your time. The stain may feel dry on the surface but still be wet below the surface causing the finish to bubble.

To prevent air bubbles from occurring at all follow these tips.