[velocette]

Glass bead blasting is a nice way to gain a smooth satin finish, removing little or no base metal. The glass beads actually peen the surface with may tiny little depressions shaped like the beads themselves.
Blasting pressure is kept low (20 ~ 50 psi) to avoid fracturing the little glass beads. Fractured beads from higher pressures result in sharp edged beads which will cut or remove material from the substrate.
If you are doing the bead blasting yourself, be certain to buy high quality beads that have NOT been used previously (no fractured beads) be certain that your blast nozzle is new or at least in very good condition and of the proper size for your compressors & regulators output, wear good eye protection and a dust mask. (even when using a booth) and start with your blast pressures fairly low.

Roger