Different types of abrasive materials are used in sandblasting. The most abrasive of abrasive materials are shot blasting (with metal shot) and sandblasting (with sand). Moderately abrasive variants include glass bead blasting (with glass beads) and plastic media blasting (PMB) with ground-up plastic stock or walnut shells and corncobs.
There are several advantages to glass bead sandblasting. It’s a moderate solution for treating sensitive surfaces and does not interfere with coatings as it is non-reactant. No residue or embedded contaminants are left, and glass bead sandblasting does not cause any dimensional surface change.
However, glass bead sandblasting also has some disadvantages. It is not as fast as other media at cleaning and does not last as long. Glass is not as hard as steel grit, steel shot, and even coal slag. Therefore, it does not clean as fast as these blast medias. Furthermore, glass beads do not leave a profile, which can be problematic if you need a profile for your paint to adhere. Finally, compared to steel grit or shot and aluminum oxide, glass bead blast media can only be used a few times, compared to numerous times with steel blast medias.