Something is amiss here! Our Varathane Ultimate Oil-Based Polyurethane should not be particularly thin or thick, the viscosity is typical of a traditional oil-based polyurethane. Settling can occur in the can over time, and if the contents are not stirred well before use, this could cause the polyurethane on the top to be very thin, as the solids would be at the bottom. We recommend applying with a good quality, natural bristle brush, cleaning brushes and application tools with mineral spirits as needed. We recommend allowing a minimum of 4 hours between coats, ensuring the previous coat is hard to the touch before applying the next coat. - Rust-Oleum Product Support 2