If you're trying to find a good abrasive for your DIY painting project, you might want to look at baking soda, or sodium bicarbonate. While baking soda has emerged as a major environmentally-friendly cleanser in the home because of its abrasive yet gentle effects, it's also gained a good reputation in the industrial and hobby abrasive market. However, like any abrasive material, baking soda has its issues.
Knowing how to handle the material and knowing what to expect when you use it will help make the abrasive blasting portion of your project easier to complete:
Take Your Time
Baking soda is effective, but it is also gentle, so it takes longer to abrade surfaces. Go slowly and plan to spend several hours using the abrasive. Since the time it will take to abrade can vary by surface and material, test the baking soda abrasive by timing how long it takes to complete a section of your work, and multiply that time by the number of equivalent areas on the project. For example, if you're trying to get old paint off a bike frame, work on one quarter of the frame. Since you'll have three quarters left to go, multiply that time by three.
Rinse and Repeat
Baking soda is also prone to leaving a white film on everything. If you've ever used it to scrub a stainless steel sink, you'll know exactly what that film is like. Be sure to rinse off all parts that you abraded with the soda. Let them dry, and if you see the white film reappear, give them another rinsing. As with your sink, it might take a couple of rounds of rinsing, but the film will disappear.
By the way, getting rid of that film is crucial. Any substances you try to put on the surface after using the soda abrasive won't stick that well if the film is present. That's because the substances, such as paint, will stick to the film particles instead of the surface. That doesn't create a lot of stability. Get the film off so the paint or other substances stick to the actual surface.
Use the Right Type
Don't top off your industrial baking soda supply with kitchen baking soda. Both are sodium bicarbonate, but the kitchen stuff is finer, so it will take much longer for it to do anything to the surface being abraded. It will also clog your sprayer. You know how kitchen baking soda forms those really annoying clumps that block the opening to the baking soda box and prevent you from pouring out the soda? Imagine those in the sprayer. Not pretty, and a definite time waster.
Beware the Dust
Baking soda abrading can get pretty dusty, so protect yourself accordingly. Respirator, goggles, gloves, and old clothing are required. Lay down a tarp where you're spraying to catch soda that drops after hitting the surface of the item you're trying to abrade. Isolate the spraying area if possible, or cover all surrounding items with more plastic. Baking soda can be a wonderful material to work with, but you do need to use it properly and carefully.
To learn more, contact a company like Steel Coatings Inc. with any questions or concerns you have.