Phil Vargas, a sandblaster on Product Plant Barstow, Marine Depot Maintenance Command, shuts the door of the rotary blaster, May 24. The rotary blaster is an automated machine that is used to blast multiple parts at one time without supervision. - Phil Vargas, a sandblaster on Product Plant Barstow, Marine Depot Maintenance Command, shuts the door of the rotary blaster, May 24. The rotary blaster is an automated machine that is used to blast multiple parts at one time without supervision.