Few things can harm a metal surface as extensively as rust. That's why rust is commonly called "car cancer" in the car restoration culture. Removing rust is the first step in repairing a panel. There are various chemical products that can convert the rust to a safe compound, but using these products can be time-consuming. With media blasting, or abrasive blasting, you spray a chosen media onto the surface under high air pressure. There are several different types of media; it's critical to choose the right one for removing rust.
Sand has been used longer than any other type of blasting material, but blasting with sand is extremely dangerous because the dust created can cause serious respiratory damage. That's why sand blasting is becoming increasingly rare. There are several alternatives that can remove rust just as effectively. Ground glass is popular for removing rust, as is aluminum oxide. Both materials will also remove paint and carbon. Silicon carbide is an adequate alternative, but it will take longer to cut though the rust, so you must use more of the material.
No matter the type of media, always wear a NIOSH-approved respirator, safety goggles and leather work gloves to prevent injury. When blasting the rusty surface, spray the media at an angle to the surface rather than directly onto it. Avoid spraying the same area for more than a few seconds; otherwise the metal panel will get hot and warp.
