Hi @David4321,
In a damp, rainforest environment, rust can be tough to control even on well-made, heavy-duty hinges. Since you’ve already used rust-proof enamel paints without success, the key now is to remove the existing rust thoroughly and rebuild protection from the metal surface upward.
Start by scrubbing away all loose rust and paint using a wire brush, sanding wheel, or a drill-mounted wire cup brush. If some rust remains in pits or crevices, apply a rust converter or dissolver, such as Ranex Rustbuster or White Knight Rust Guard Rust Converter, to neutralise and stabilise it before painting.
Once the surface is clean and your rust converter has completed its chemical reaction, wipe it down with methylated spirits to remove any dust, oil, or residue. Allow it to dry completely, as even a small amount of trapped moisture can cause new rust to form under your coating.
Next, apply a rust-inhibiting metal primer. Dulux Metalshield Etch Primer is an excellent choice for creating a solid base that prevents oxygen and moisture from reaching the metal.
After the primer has cured, follow up with a tough, weather-resistant topcoat such as Dulux Metalshield Epoxy Enamel. Apply two thin, even coats, making sure to cover hinge joints and exposed edges carefully.
To keep rust from returning, it’s worth doing a bit of regular maintenance as any weakness in the coating can allow water in. Once or twice a year, check for chips or small rust spots and touch them up promptly.
Over time, this combination of deep surface preparation, quality coatings, and light maintenance will give your gate hinges much better protection against the elements.
Let me know if you have any questions.
Jacob
Metal gate hinge
