What is the Difference Between Sand Blasting vs Soda Blasting?
What Is Sand Blasting?
Sandblasting is the colloquial name often used to describe the wider field of abrasive blasting. Abrasive blasting is the process of applying an abrasive material, such as sand, to an object at high pressure. It is often used to strip paint from machinery and metal, but it has many other uses. Despite it's name, sandblasting is not confined to the use of sand.
Other common varieties of abrasive blasting include:
- Glass bead blasting
- Soda blasting
- Walnut shell blasting.
- Coconut shell blasting
You may recognise the chemical Sodium Bicarbonate that is used in sodablasting also has a more common name: Baking Soda!
I actually have it on good authority, via Tony Heyblom of United Sodablasters, that once the Sodium Bicarbonate has been used, you can still use it in cooking! After you pick out the paint and grease...of course.
What Is Soda Blasting?
Soda blasting is a relatively new technology in the field of abrasive blasting. While it is technically used as an abrasive, many professionals in the field consider soda blasting non-abrasive. Specially granulated sodium bicarbonate is applied at high pressure upon a surface, to remove contaminants or smooth the surface.
Because sodium bicarbonate shatters on impact, it is much gentler than sandblasting or media blasting. It is suitable for use upon chrome, plastics and even glass if applied correctly. Soda is also used to a lesser extent to remove mold and smoke damage, as sodium bicarbonate is a natural deodorizer.
Positives of Soda Blasting & Sand Blasting
Soda Blasting Positives
Sand Blasting Positives
Soda blasting is environmentally friendly and biodegradable
Better for industrial applications
Soda blasting is gentler than sand blasting.
More effective at removing rust than soda blasting
Does not produce excess heat. Will not warp or pit metal surfaces
Quicker cleaning than soda blasting
Removes grease and paint up to 15x quicker than industrial hydro-blasting
Sodium bicarbonate cleans mold and deodorizes smoke fires.
Non-toxic and water soluble
Prevents further rusting
Soda blasting can be applied on plastics, chrome, and wood
Environmental Effects of Soda Blasting
Similar to walnut-shell blasting, the use of sodium bicarbonate is relatively environmentally friendly. Soda is water soluble, and will not build up in soil or residential areas, whereas sand or glass will not dissolve.
While you can safely breathe small amounts of sodium bicarbonate while soda blasting, it is recommended you wear a breathing apparatus such as a quality gas mask, or employ the use of a professional soda blaster, who will wear one.
Costs of Soda Blasting
The running costs associated with soda blasting (The cost of chemicals, machinery, and labour) are marginally higher than the costs of sandblasting, so you can expect to pay a bit more for the environmentally-friendly option.
Soda blasting is quicker and easier to set up. Because you don't need to isolate easily damaged parts such as windows or plastic frames, time is saved compared to sandblasting. And remember, time is money
Whereas sand and other materials such as garnet have a strong chemical structure, sodium bicarbonate does not. Once soda has been used, it shatters into a fine powder because of friability. For this reason, it can only be used once, and the running costs of soda blasting increases.
Negatives of Soda Blasting & Sand Blasting
Soda Blasting Negatives
Sand Blasting Negatives
The running costs of soda blasting are higher
Not recommended for softer materials such as glass, wood or plastics
Can leave a white film on the surface being cleaned
Generates heat through friction
Can warp or damage softer materials, depending on the medium used
Will not sanitize or deodorize like soda blasting
Inhalation of sand particles can cause silicosis
Environmental Effects of Sand Blasting
Abrasive blasting generally lends itself well to a host of environmental impacts, none of which are positive. However, the use of abrasive materials such as walnut shell and coconut are biodegradable, and hence more environmentally friendly.
The detrimental effects of sandblasting really depend on the medium actually used. When choosing a medium, take care to make a choice that will not clog or harm local water supplies, and ensure that is free from heavy metals.
The use of a booth removes almost all environmental effects of abrasive blasting. The curtain on such a booth captures the dry material used in blasting, so that it can either be reused, or disposed of carefully.
The environmental impact of sandblasting is entirely dependent on your choice of medium, and how you choose to contain it. So choose carefully.
Costs of Sand Blasting
Sand blasting is cheap, quick and effective. The range of materials that can be used for sandblasting are not simply limited to sand. Almost all of these materials can be reused, and are cheap when bought in bulk amounts. These factors make it a cheaper, albeit more time-consuming, option than soda blasting.
Sandblasting is more suited to heavy industry. Time is not wasted removing glass or plastics from heavy machinery, so it becomes a cheaper option than soda blasting.
DIY Soda Blasting
I've seen industrial soda blasting equipment sell for upwards of $50,000! If that's a little out of your budget, you can watch the video above, courtesy of Garage Night, and knock one up for yourself for around $25 - $30.
Which is Better: Sandblasting or Soda Blasting?
From the tables above, it is clear that soda blasting is a more versatile option than sandblasting. Having said that, there are arguments representing both points of view, depending on the intention of the blasting methods. For example, sandblasting may be cheaper, but there's no point using it to clean rubber. Likewise, soda blasting is more environmentally friendly, but it's generally too expensive for small 'backyard-type' projects.
Soda blasting is a preferable option to sandblasting in the cleaning of aluminium sheet-metal, because it is gentler. Sodium Bicarbonate shatters on impact, so it does not warp or damage the softer metals like aluminium, or react chemically with it's surface.
Sandblasting is often preferable to soda blasting in the cleaning of industrial equipment. It removes grease and paint quickly and indiscriminately. Because it is cheaper, it is best used in long-term contracts or where consistent work can be found.
Many cars today are sandblasted, as this is the cheaper option. As to which option does the job better, it really comes down to the abilities of the blaster. More care should be taken with sandblasting a vehicle however, as there is a risk of damage to the car body or windows.