APPLY RUSTSEAL IN THIN COATS
Remember that RustSeal should be applied in THIN coats. Applying too heavily, will cause running and/or sagging on vertical surfaces, and possible bubbling on horizontal surfaces. As RustSeal cures, it releases a small amount of carbon dioxide. If allowed to "puddle", the top of the RustSeal directly exposed to the ambient humidity in the air (the actual catalyst for RustSeal) will begin to "skin" over. This "skinning over" is much like that of chocolate pudding and blocks the release of the afore mentioned carbon dioxide causing bubbles. By applying thin coats, this film cures through and through all at once.
MORE TIPS & TRICKS
RustSeal Fix-It Guide: This guide helps you quickly identify the causes of and the recommended solutions for the most common issues that could occur for RustSeal.