Rust Killer: Secret Weapon for Metal Surfaces
When it comes to painting exterior metal surfaces—like railings, gutters, metal roofs, or fencing—one of the most common challenges painters face is dealing with rust. If left untreated, rust will not only ruin the finish but also continue to spread beneath the paint, compromising the integrity of the surface. This is where rust killer becomes an essential part of a professional painter's toolkit.
What Is Rust Killer?
Rust killer, also known as rust converter, is a chemical solution designed to halt the corrosion process on metal. Rather than removing rust completely (as rust removers do), rust killers chemically convert rust (iron oxide) into a stable, paintable surface. Most products turn rust into a black, inert substance—typically iron tannate or a similar compound—which helps prevent further corrosion.
How Does It Work?
Rust killers typically contain a combination of tannic acid and organic polymers. Here's how the process works:
- Preparation: The surface must be dry and free from loose rust, flaking paint or dirt. Use a wire brush or sandpaper to remove loose particles.
- Application: Apply the rust killer with a brush, roller, or spray. It will react with the rust and usually turn black as it works—this is normal.
- Curing Time: Let the rust killer dry and cure fully. This can take a few hours to overnight, depending on the product and conditions.
- Topcoat: Once cured, the surface is ready for priming and painting. Some rust killers even act as a primer themselves, making the job quicker.
Why Use Rust Killer Instead of Removing Rust Completely?
For professionals, especially those on a tight schedule or working on difficult surfaces, rust killer saves time without compromising results. It’s ideal when:
- The rust is moderate but not deep enough to compromise the structural integrity
- The metal surface is complex or awkward to grind or sand
- A quick turnaround is needed without sacrificing durability
Best Practices for Professional Use
✦ Read the label: Different brands have different formulations—some require topcoating within a certain time frame.
✦ Don’t skip surface prep: Rust killer isn’t magic—it won’t work well on greasy, dirty, or flaking surfaces.
✦ Use the right primer and topcoat: Make sure your paint system is compatible with rust-converted surfaces.
✦ Don’t skip surface prep: Rust killer isn’t magic—it won’t work well on greasy, dirty, or flaking surfaces.
✦ Use the right primer and topcoat: Make sure your paint system is compatible with rust-converted surfaces.
Popular Brands Available in Australia
- Dulux Metalshield Prep
- Bondall Ranex Rustbuster
- Septone Rust Converter
- Fertan Rust Converter
Final Thoughts: On Rust Killer
Using rust killer not only ensures a cleaner, longer-lasting finish but also helps maintain your reputation for high-quality, professional results—especially in Australia’s harsh, rust-prone environments.
Thinking about repainting? Let our experts guide you with a no-pressure, free consultation.