Method for assembling a head stack assembly with a disk drive base utilizing a tooling mandrel

A method of assembling a disk drive, the disk drive including a disk drive base and a head stack assembly, the head stack assembly including a pivot bearing cartridge, the pivot bearing cartridge including a shaft and a sleeve disposed about the shaft, the shaft including a shaft first end with an engagement feature, the shaft defining an axis of rotation and a shaft outer circumferential surface, the sleeve defining a sleeve inner circumferential surface disposed towards the shaft outer circumferential surface, the method comprising:

• a) providing a tooling mandrel, the tooling mandrel including:
• i) a retainer element defining a longitudinal axis and including a distal end, the distal end being sized and configured to engage the engagement feature of the shaft first end with the longitudinal axis being aligned with the axis of rotation;
• and
• ii) at least two tooling fingers disposed about the retainer element, the tooling fingers being angularly fixed to the retainer element with respect to the longitudinal axis, the tooling fingers each include a tip portion, each tip portion being sized and configured to engage the pivot bearing cartridge through cooperative radial movement with respect to the axis of rotation with the distal end of the retainer element being engaged with the engagement feature of the shaft first end;
• b) aligning the longitudinal axis of the retainer element with the axis of rotation of the shaft;
• c) engaging the engagement feature of the shaft first end with the distal end of the retainer element;
• d) engaging the pivot bearing cartridge with the tooling fingers through cooperative radial movement of the tip portions with respect to the axis of rotation;
• e) positioning the pivot bearing cartridge in mechanical communication with the disk drive base using the tooling fingers;
• and
• f) attaching the pivot bearing cartridge to the disk drive base while maintaining engagement of the engagement feature of the shaft first end with the distal end of the retainer element and engagement of the pivot bearing cartridge with the tooling fingers.