How to Remove Rust With an Ultrasonic Cleaner

Ultrasonic cleaners use sound waves broadcasted through an aqueous solution to remove contaminants like rust, paint and oil from metal surfaces. According to the National Center for Remanufacturing & Resource Recovery’s (NC3R) study on ultrasonic cleaning, the ultrasonic sound waves cyclically produce both low- and high-pressure fronts against the metal surface. The initial low-pressure front causes air bubbles to form. Then the following high-pressure front breaks the bubbles, helping to scour away contaminants. With the addition of a detergent solution to the water, the chemical reaction between the detergent and the part's surface increases the cleaning ability.

Things You'll Need

  • Bench-top ultrasonic cleaner
  • Rusty parts
  • Water
  • Cleaning solution
  • Neutralizer
  • Fill the ultrasonic cleaner tank with water. Remove the inner parts basket and set aside.

  • Add cleaning solution to the water. The type of solution depends on the type of material you are cleaning. Some manufacturers of ultrasonic cleaners sell compatible cleaning solutions.

  • Turn on the ultrasonic cleaner and run for 10 minutes to allow the solution to distribute evenly.

  • Obtain a rusty object. It can be a car part or tool, or any metal object that has rust on it and is small enough to fit inside the ultrasonic cleaner.

  • Remove any loose rust with a cloth if the parts are delicate or a wire brush for stronger parts. This will increase the effectiveness of the ultrasonic cleaner.

  • Place the part or parts to be cleaned in the basket. Be aware of any rubber or plastic gaskets or wiring that may be damaged by the cleaning solution. If possible, remove anything that is not compatible.

  • Immerse the basket in the ultrasonic cleaner and allow the parts to soak for at least 30 minutes. You will see bubbles forming around the parts as the ultrasonic waves cause minute jets of water to break against the surface and release the rust. Depending on how rusty and the number of parts immersed, the water will become dirty.

  • Lift the basket from the cleaner. Rinse the parts in water to remove any cleaning solution.

  • Inspect the parts to verify all rust has been removed. Heavily rusted parts may still have small parts of rust clinging to them. You can try to remove these manually or run them through another cleaning cycle with fresh solution.

  • Neutralize the cleaning solution before disposing the waste water. See your state and local regulations for waste disposal.