On Fri, 15 Jan 2016 06:48:18 +1100, "Rod Speed"
wrote:



"Micky" wrote in message
.. .
On Thu, 14 Jan 2016 21:12:53 +0700, JJ wrote:

On Thu, 14 Jan 2016 05:44:50 -0500, Micky wrote:
What wears out in an HDD? Is it only the tone arm that breaks? or
can the bearings the platter rides on break??? Good watches use
jewels, rubies, as bearings; and cheap watches use metal. What do
hard drives use?

Most of the causes is due to combination of heat and force.

IMO, the arm and bearings and are pretty solid but it's not impossible for
them to break - depending on the material and manufacturing quality.

So what clicks when the drive breaks?

That's mostly the drive moving the heads to a known spot to recalibrate
the position of the head arm. When the drive can no longer read the
tracks, say because the head preamp has failed or some other part of
the system that reads the tracks has failed, it keeps trying to recalibrate
and never succeeds and that can produce audible clicking in some drives.

This would account for how one of my hdds clicked 2 or 3 times on
windows start, 4 or 5 times, before finally failing several months
from the start of all this. Well, when it failed somehow Windows
files coudl no longer be found. But I was prepared with 3, count
'em, 3, backups of the whole drive.

https://en.wikipedia.org/wiki/Bearing_(mechanical)#Service_life

Does the spindle really ride on an air cushion?

From where did you have that thought?

From a fairly detailed webpage.

But you confused the spindle with the heads.