If you’ve ever watched YouTube videos of water blasting with an odd sense of enjoyment, you’re going to love soda blasting.
Soda blasting is when sodium bicarbonate particles –baking soda – are blasted onto a surface using compressed air or water. The soda is abrasive, easily removing a number of substances, but without the harshness of sand blasting.
Air or water and the sodium bicarbonate are mixed, pressurised, and then forced through a blast nozzle. This nozzle can be a range of different sizes and shapes, depending on what you’re removing, and what kind of surface.
What’s The Difference Between Soda Blasting and Sand Blasting?
There are three main differences between soda and sand.
Sodium bicarbonate has standard particle sizes between 60 and 70 microns. Sand is between 100 and 500 microns. This means that sand is far more abrasive, but also far more aggressive than soda blasting.
Soda is also 2.4 on the Mohs hardness scale (a fingernail has a hardness of 2.5, for comparison). Other common blast materials are much harder, with window glass about 5.5, sand 6 to 7, and aluminium oxide at 9. This means that soda is less likely to damage the surface that is being sprayed.
Sodium bicarbonate is a single-pass media. This means that when it blasts against a surface, the soda particles explode into tiny bits, leaving a fine dust that can’t be used again. However, sand can be used again and again.
Why Use Soda Blasting?
Soda blasting is relatively new. It was invented in the 1980s, specifically for restoring the Statue of Liberty. The statue could not be cleaned using sandblasting for multiple reasons: It had many coats of paint and coal tar and yet was made from thin copper plates which could be damaged easily. The internal passages are narrow and difficult to ventilate, so the dust from highly abrasive blasting would have caused problems.
The use of soda blasting solved all these problems, securing it a role in many projects. While sandblasting is good for many things, a metallic surface will be damaged by the sand propelled at it.
- Because soda’s particles are smaller, it doesn’t damage/ profile the surface that’s being blasted.
- It’s environmentally friendly and non toxic to humans and animals, making it safe for use in food processing applications. It’s easy to clean up
- Soda is non-acidic (with a pH of 8, it’s quite basic/alkaline), meaning there’s no risk of causing rust to metallic surfaces – leaving the sodium bicarbonate on surfaces can even help to prevent flash rusting
- It is water soluble, making it easy to clean
- Baking soda, as anyone who cleans the home knows, is a natural deodoriser, making it ideal for use on projects where there is smoke damage or other forms of odour
- It won’t damage bearings, hoses, gaskets and seals. This means less time to set up the area for blasting as gaskets/ plastic don’t need to be isolated and protected.
What Can Soda Blasting Be Used For?
There are many uses for soda blasting. Anything where you don’t want to damage the substrate, but you still need an effective and fast way to remove a surface layer. This includes:
- Removing paint
- Graffiti removal
- Cleaning machinery in food processing plants
- Cleaning and stripping car parts/ frames
- Cleaning ship hulls
- Restoration of historical statues or monuments
- Removing painted lines from roads
- Removing grease, grime and carbon from machinery and parts
- Gum removal
- Mould removal
- Fire restoration
- Wood stripping, cleaning and restoration
- Cleaning calcium deposits
Soda blasting is used extensively in the cleaning and maintenance of power plants, electronics, water treatment centres, and the aerospace industry.
However, there are some applications when soda blasting shouldn’t be used:
Don’t use soda blasting around plants, especially those that prefer acidic soil. Hydrangeas might change from blue to pink petals.
Other traditional forms of blasting will be more effective on smooth surfaces. Soda doesn’t attach as well to smooth surfaces and may require priming or profiling to be effective.
Despite the fact it’s environmentally friendly and water-soluble, PPE must be used to prevent inhalation/ irritation of the dust to the mouth, nose, eyes, throat, and ears.
Is Soda Blasting Right for Your Project?
Give us a call or flick us an email to discuss if soda blasting is right for you. For some projects, traditional water or sandblasting could be more effective, and we want to make sure you optimal results. If you’re in Wellington, Christchurch, or the upper South Island, get in contact to find out more.