Structure and enclosure assembly for a disk drive

A data storage disk drive comprising:

• at least one disk surface mounted for rotation about a spindle motor shaft;
• at least one data transducer head for reading and/or writing data to respective disk surfaces;
• an actuator for moving said at least one data transducer head across respective disk surfaces;
• said actuator including an actuator bearing shaft;
• a device enclosure for enclosing said at least one disk surface, said at least one data transducer head and said actuator, said device enclosure defined by a base casting and a cover casting, each of said base casting and said cover casting having a mating surface along the length of the data storage disk drive, said base casting including die-cast generated predetermined zero draft geometries for mounting said spindle motor shaft and said actuator bearing shaft at spaced apart locations;
• said at least one disk surface mounted on said spindle motor shaft and said actuator being removably positioned for independent assembly and removal with said base casting of the disk drive;
• a breather filter and wherein said cover casting of said device enclosure includes an integral diffusion path for controlling airflow to said breather filter and an integral channel for controlling airflow from said breather filter to a predetermined region within said enclosure, said predetermined region located near said spindle motor shaft;
• and
• said actuator further includes a first pole-piece magnet assembly and a second pole-piece magnet assembly mounted by said base casting die-cast generated predetermined zero draft geometries.