Disclosed is a clamp fastener that includes a convex head to prevent damage due to contact from a cover of a disk drive. The disk drive comprises a disk, a spindle motor, a disk clamp mounted to a top surface of the disk, and a clamp fastener. The clamp fastener includes a convex head. The clamp fastener is mounted through the disk clamp to connect the disk clamp and the disk to the spindle motor such that the spindle motor spins the disk, wherein the convex head is nearer to the cover than the disk clamp.