Hi all,
With regard to removing/re-fitting the head stack, I've read that it is important to not let the heads contact the disk(s) as they are removed, yet the SD video shows the tech moving the heads across the disk surface while slowly rotating the disks, until the head stack tool can be inserted near the edge of the disks.
Can someone clarify this procedure for me?
TIA

Have you tried to contact SD on this? I'm curious what they would say. Contact them via email address: manager@salvationdata.com

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Will do.
Seems though that after reading here http://www.myharddrivedied.com/presenta ... paper.html
and here http://hddguru.com/content/en/articles/ ... k-Q-and-A/
that there's no choice in the matter and rotating the platters to stop sticking whilst moving the heads to the edge is the best that can be done.
Contact may not be desirable, but is obviously not critical.

I usually try to spin at ~2 rotations per second or so, any less and it may stick. Needs air bearing.

Good luck with your SD tools trust no one

Ok, got a reply back from SD and it seems they have no special technique either, saying simply that 'the best way is to move the head to the outer edge carefully by hand'.
I've wondered how manufacturers assemble them in the first place, perhaps they have a method of powering the motor to spin the discs while they load the heads to the centre?


lol, I'm still eyeing off all theories still at this stage, including cooking up my own design.
I've picked up a couple of good hdd's of the same model as mine to rehearse on.
I'll be taking just one baby step at a time on one of them, then backtracking to see if the drive still works, ultimately being able to completely dismantle a drive, put it back together and have it still work, and to be able to repeat this a few times on the same drive to prove it wasn't just luck.
If I can achieve this, then it will be with some confidence that I can recover the data of my drive which has a severely jammed spindle motor.

My first step on that drive will be to make up a tool to try and unjam the motor.

No chance with this - I could move it, turned it a full turn but it felt like the whole bearing assembly started to rotate. It's fully jammed!
I've started the rehearsals on another drive, so far have gotten up to removing the cover and refitting it and the drive still works.
Will start a new thread in the data recovery forum as I make more progress.

Sometimes it is possible to unstick the motor, but typically I have low success with this. Usually the motor can get unstuck, but then there is "eccentricity" or, simply put...a wobble in the spin.


Is this a WD drive your working on? WD Desktops are the only drives with severe headstack alignment issues; other brands typically don't suffer from these problems, so there is no need to practice removing the lid and putting it back on and see if it works. The best way to practice is to completely remove the headstack, and then put everything back togather and see if the drive still works; notice things like...does it work as well as it did before? Run a surface scan before and after...what is the difference after you performed the removal? These things can help gauge how much a headstack can take. Maybe next you can remove the head stack, and purposely make some sort of minor mistake, and then see how that mistake affects the drives performance.


Regards,

Hi Russ, thanks for your input.
Yes, it's a WD1600 caviar se model. I was fairly certain that my efforts to unjam it would be fruitless, I was at the computer when it first spat it. It slammed to a halt with a loud screech!! [ouch - that's gotta hurt!]
It was my D drive, so the computer still works fine, just lost the data on D. Not to serious, many things that were on D are also on other external drives.

Yes, performance is a lead indicator and is something I'm paying close attention to.
I'm also mindful of the fact that if the drive does fail at some point, that it won't necessarily be that step that caused the failure, as the repeated exposure of the drive internals to the outside world [my environment is clean, but not level 10 clean] may eventually cause the drive to fail anyway.

Your comment about a deliberate mistake is spot on! That's exactly what I had planned, to first see if I can completely dismantle and reassemble being as careful as possible and if successful, to then see how 'brutal' I can get with it and still succeed.
My 3 main areas of concern are contamination, head protection and alignment of platters. The platter alignment is the biggest nightmare of them all, there's no getting 'brutal' with that, it has to be perfect or it's a bin job!

I've continued this thread here
recovery-jammed-wd1600-caviar-platters-head-hsa-t14583.html

You may be surprised about what you learn about platter alignment by deliberately breaking alignment; get a Seagate 7200.10 drive, and spin the platters in various directions, then re-tighten the spindle cap, and see you results =).


The servo is the key factor in alignment, how it was written and for what tolerances it can withstand.


The rules are different for every manufacturer, and every series/family...the rules can change without warning, this makes things interesting to say the least.

Hi Russ, thanks for the heads-up, if I get one I will try that

This is how it should be done
http://www.youtube.com/watch?v=pWINc52zuv0

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