Soda blasting is a relatively new technique for paint, mold and surface rust removal that is slowly gaining popularity. Unlike sandblasting, soda blasting uses bicarbonate (also known as baking soda) to strip finishes off a substrate. While sandblasting equipment can be used for soda blasting, the bicarbonate abrasive is relatively gentle when compared to the grit usually used for sandblasting. To figure out what the best instances are to use soda blasting, consider the following attributes of the process.
Great for Soft Metals and Woods
Soda blasting was developed to work well on soft metals like copper (it was originally developed for use on the Statue of Liberty), but also works well on wood. Unlike sandblasting it will not scratch wood or metal surfaces below the paint. The key to soda blasting correctly is the amount of pressure that is applied. The soda is sprayed onto a surface, just like a pressure washer, at an oblique angle. If the pressure is too high, the substrate will dent or warp. At the right pressure, one should be able to strip away as little as one layer of finish at a time.
It Is Cleaner
If a finish needs to be stripped off of a surface that is outside, soda blasting is ideal. When sandblasting, the grit that is expelled from the blasting hose must be swept up after the stripping has been finished because the grit is a silicate that is harmful to the environment. The bicarbonate from a soda blaster, however, will simply dissolve into the ground or wash away during the next rain storm.
Furthermore, the dust produced from sandblasting grit can be toxic if drawn into a person’s lungs. The dust produced from the soda used in soda blasting is not toxic. As a soda blaster strips a finish, the finish may be reduced to tiny particles that can float in the air, and these particles may be toxic if inhaled. For this reason, it is still important to wear protection when using a soda blaster.
Removes Grease and Rust
Soda blasting will not only remove paints and lacquers, but it is strong enough to strip away surface rust, grease, and other debris from substrates as well. The process is actually better at removing grime from surfaces than harder organic blasting materials like walnut shells because it can enter and clean smaller cracks and crevasses that the wider organic compounds cannot reach.
Some surfaces, such as wood, can be damaged by the heat caused by the friction of grits used in other blasting processes. Because soda is a gentler abrasive, it produces lower amounts of friction and, consequently, less damaging heat.
Using soda blasting is an excellent method of cleaning. However, it's not right in every situation, so let this be your guide.