Underbody Rust Treatment

Underbody treatment combats rust.

Rust occurs when stones or other road surface debris cause chips that expose the bare metal of a vehicle's underbody. When moisture is introduced, either through water or humidity, rust begins to form almost immediately and causes the metal to corrode, leading to rust and, eventually, holes in the metal.

Inspect

Stop rust before it starts. Under normal conditions, cars begin to show rust between three to five years, but earlier inspection is recommended. Regularly check the areas most likely to be affected by rust, such as in and around the wheel wells.

Retouch

If you find rust, use fine sand paper to remove the rust and sand down to bare metal, then vacuum the surface to remove any dust. Using a brush, carefully apply a coat of touch-up (rust) paint or sealant to the affected area.

Rust Convertors

Modern rust converters are a type of primer containing tannin and an organic polymer that can be applied directly onto rust without the need to first sand the surface. The tannin changes iron to iron tannate, stabilizing the metal and the polymers form a protective layer. Converters must be applied in a low-moisture environment, such as a closed garage on a warm day.

References

• "Automedia": Rust never sleeps