A device for centering and securing data storage disks to the hub of a
spindle motor in a hard disk drive has a chamfer and a countersink on the
top of the spindle motor shaft center. During the hard disk drive
assembly process, a disk centering tool engages and uses these features
to locate and center the disks that are installed on the spindle motor.
The features are closely toleranced to provide a very precise centering
feature for mounting and aligning the media disks with respect to the hub
and the spindle motor. The present design reduces the complexity of the
tooling and fixtures required to complete the assembly. As a result, the
overall part cost is reduced and the manufacturing yield is improved.