Sodium Bicarbonate Blast Cleaning

Paint and some rust can be stripped from cars using sodium bicarbonate blasting.

Sodium bicarbonate is an inert, white crystalline substance, also known as baking soda, that can be used as an abrasive and is even present in some whitening toothpastes. As an abrasive, the substance has a hardness of 2.4 on the Mohs' scale, compared to diamond at a hardness of 10. The relative softness of the substance allows it to be used to strip softer coatings from a harder base, such as paint from metal.

Things You'll Need

• Sodium bicarbonate
• Blasting machine
• Goggles, safety glasses or face shield
• Dust mask or paint respirator
• Ear protection
• Forced air blast hood or full face respirator if blasting inside a vessel

Instructions

1. Buy a sodium bicarbonate blasting machine such as the "Soda Blast" machine from the Soda Blast Company or the Model 150 CS Sodium Bicarbonate Blast System from Titan Blast Cleaning Equipment. Alternatively, according to the Soda Blast company, you could use other blasting machines, but to avoid sputtering of the media, you should fit a metering valve to the machine.

2. Choose the size of particle you want in your blasting media. Sodium bicarbonate can be produced in different particle sizes, and it should be irregularly shaped to improve cleaning capability.

3. Put on your personal protective equipment. Even though sodium bicarbonate is not classified as hazardous, the powder can form dust during the blasting procedure, and the material that is being removed from the object may be hazardous. The minimum recommended safety equipment to be worn is a National Institute for Occupational Health and Safety-approved dust mask or paint respirator, ear protection to protect from noise levels and goggles, safety glasses or a face shield. As the powder is gritty, you should not wear contact lenses so as to avoid eye irritation. If you are blasting inside a vessel, you should also wear a forced-air blast hood or full-face respirator. Ensure the area is ventilated and that there are no other people in the vicinity without personal protective equipment.

4. Fill the blast cleaner with the sodium bicarbonate. There is no need to degrease the item before blasting it, as the particles will remove the grease as well as the paint or other layers to be removed. Point the blasting nozzle at the item to be cleaned and keep it at the distance recommended by the individual machine's instruction manual.

5. Rinse the item down with water to remove traces of the sodium bicarbonate if you know the stripped material from the cleaned surface is non-hazardous, and allow the water to run down the drain. Dry and oil metal surfaces in order to prevent rusting. If the stripped substances are hazardous, collect them using appropriate protective equipment and dispose of them according to the instructions on their Material Safety Data Sheets, which can be obtained online or directly from the manufacturer.

Tips & Warnings

• Sodium bicarbonate blast cleaning does not remove rust well. Blast clean the item first and then sand by hand in order to remove stubborn rust.

• Avoid contact with lime dust, as the mixture may form caustic soda. Also keep sodium bicarbonate away from temperatures exceeding 228 degrees Fahrenheit, as the substance will decompose.

References

• Soda Blast: MSDS Sodium Bicarbonate
• Soda Blast: Sodium Bicarbonate
• Titan Abrasive: Sodium Bicarbonate
• Super Chevy: Sodium Bicarbonate Paint Stripper