Every now and then I have access to a failed HD. For whatever reason, it just isn't working anymore, it usually means replacement and if I'm lucky I got some/all data from it that the client requires. Once done, they no longer need the broken HD, I offer to dispose of it. If they agree, I teardown the HD for scrap.
In this case of a Seagate 320Gb HD(model ST3320820AS, I found what was causing the issue. It had the COD = click of death sound. Upon teardown the best estimate of the problem was a parking arm was engaged or wouldn't release. Even under full open drive, the parking mechanism just wouldn't release so I can then remove the platters. Maybe, it wasn't the problem, but repeated L/R movements of the r/w heads reproduced the click sound. There you have it, very likely good platters but a simple broken mechanism at fault. FYI- the platters themselves were unique at least to me, because they were "thick" much more so than others I've seen.
One day, I'll make some platter clocks for nerds/geeks.
tada -----Willy ![]()

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