How to Remove Rust From a Padlock

How to Remove Rust From a Padlock
Written By
Ciele Edwards
Ciele Edwards
Published: Jan 27, 2010
Updated: Nov 20, 2021
2 minute read

If the rust is not promptly removed, it will continue to spread and eat away at the iron in the lock. In addition, the more rust that builds up on a padlock, the more difficult the lock will be to open. A rusted padlock is not always a lost cause. You can remove rust from a padlock in order to keep it in good shape and functional.

Things You Will Need

  • Paper towels
  • 80-grit sandpaper
  • Rust conversion solution
  • Phosphoric acid
  • Degreasing agent
  1. Wipe the excess rust from the padlock with a damp paper towel.

  2. Scrub the exterior of the padlock with sandpaper to get rid of as much of the rust as possible. 80-grit sandpaper is ideal for this job, but you may also opt to use a kitchen scrubbing pad or a different grit of sandpaper if that is all you have handy.

  3. Rinse the lock in warm water and dry it with a paper towel or soft cloth.

  4. Soak the lock in a rust conversion solution if sanding does not remove all of the rust. A rust conversion solution will convert the rust to organic compounds that can be easily wiped away with a cloth.

  5. Soak the padlock in phosphoric acid. Do so only if the inside of the lock is so rusted that you cannot open it. Although rust conversion solution will convert exterior rust to a harmless black oxide that can be easily wiped away, you will not be able to wipe away oxidation within the lock's interior. Phosphoric acid will dissolve the rust without you needing to wipe it away--making it ideal for areas that you cannot reach, such as the inside of a padlock.

  6. Coat the padlock in a degreasing agent, such as WD-40, before returning it outdoors. Although this will not prevent future rusting, it will slow down the process.

The Drip Cap

  • Over time, metal that is exposed to the elements can become rusted.
  • Although rust conversion solution will convert exterior rust to a harmless black oxide that can be easily wiped away, you will not be able to wipe away oxidation within the lock's interior.
  • Phosphoric acid will dissolve the rust without you needing to wipe it away--making it ideal for areas that you cannot reach, such as the inside of a padlock.

Resources

Photo Credits

Comstock/Comstock/Getty Images

Comstock/Comstock/Getty Images

Ciele Edwards

Ciele Edwards holds a Bachelor of Arts in English and has been a consumer advocate and credit specialist for more than 10 years. She currently works in the real-estate industry as a consumer credit and debt specialist. Edwards has…

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