fzabkar wrote:
laptokowiec wrote:
Drive open in anything other than a clean room = game over - MYTH - if you use compressed air and won't put your fingerprints on plates and know what to do
In the 1980s I used to work on drives that had removeable disc packs. A head crash was often a disastrous affair, with debris scattered all over the pack area and sometimes inside the voice coil. After cleaning up everything with a vacuum cleaner and lint free cloths dipped in alcohol, I was always paranoid about powering up the drive for the first time. Although the pack area was pressurised with micro-filtered air, I didn't rely on this to protect the drive. Instead I opened the circuit breaker to the servo amp and spun up the drive without loading its heads. I then allowed the motor to spin for an hour, my reasoning being that this would be more than enough time for the pack area to be thoroughly purged of contaminants. In fact one minute would probably have been more than enough time, but there was a lot to lose if the drive crashed again.
I'm wondering whether such a precaution might be useful in modern drives, especially those that park their heads on a ramp. One could isolate the VCM pins, and then command the drive to spin up and remain spinning via its diagnostic interface, if necessary.
I did exactly that on my ghetto-mod drive. It was open and exposed to the air for about 8-10 minutes while I fitted the new cover.
I spun up the drive several time to let the internal air currents suck away any dust that landed on the platters. I'm sure "some" dust got in there, despite me working upside down. I had the drive suspended upside down to help prevent dust settling on the platters when I worked on it.
Also, note, if you look in the corner of many drives you'll see a cavity or small indented "holding area" this is a repository for dust and metal particles too. By design.
Well, anyways, I have little doubt that "pre-spinning" the drive can only do good. Afterall, this lets air current and centrifugal force "Wipe" the platters of non-adhesive particles. It gives the air filter a head start. WDC, had told me this "pre-spin effect" does the job in a few seconds, tops, and is already well underway prior to the heads being loaded. The tech had said at something like 40% and greater of the specified running RPM was enough to "clean" the platters.