Big T,
Keep in mind as you design this cabinet, that if the blasting system is putting out, say 8 CFM, that your vacuum system must be able to pull at least 8 CFM, or you will be blowing stuff out of the cabinet. On a little different note, when I built my cabinet, I didn't vent it...when I turned on the vacuum cleaner, The gloves stood straight out at attention, followed shortly by the Plexiglas viewing window being sucked into the cabinet...live and learn!
Stuart
