Does this work on galvanized metal?

Great question! When you apply an alkyd oil based paint like Rust-Oleum Professional High Performance Enamel Paint over zinc plated or galvanized surfaces, a chemical reaction occurs between the two materials. This process, known as “saponification”, causes a build-up of the reaction product between the zinc and the paint. Over time, the paint will begin to peel off in large sheets. This can be avoided by using a latex based primer such as Rust-Oleum Zinsser Bulls Eye 1-2-3 Primer! The primer will act as a barrier coat and prevent the reaction from occurring. https://www.lowes.com/pd/Zinsser-Bulls-Eye-1-2-3-Interior-Exterior-Multi-purpose-Water-based-Wall-and-Ceiling-Primer-Actual-Net-Contents-128-fl-oz/3439970 - Rust-Oleum Product Support 5