Moving the top cover on a WD drive for head swaps

[BytesBack]

Greetings,
I've been getting more WD drives in for head swaps recently and it seems like they have the lowest success rate for swaps among manufacturers. There are some things that I know to try to find the most compatible heads. This includes looking at same DCM, manufacturing site, date within a month, and microjogs within 200 of the corresponding one on the patient.

It seems even with as close to a 'perfect' match as possible, I'm not getting good results. I have heard of people moving the top cover on WD drives in order to get them reading properly.

Some questions for you all...
1. How do I know if the top cover is my issue when a head swap does not work?
2. What Western Digitals are affected? I know Cyl32s are. Any other families have this issue?
3. Do you have any recommendations for keeping the top cover in exactly the same spot to prevent the issue?
4. Has anyone made a graduated jig or something that allows movement of the top cover by a millimeter at a time and allow noting the positions already tried? I'll of course be trying to make tools for this myself, but I wanted to see what people have had luck with.

Any help is appreciated... Thanks!
Steve

[Eleg]

Re question 4: http://www.headalignment.com/

[drc]

Interesting. Seems more of these are popping up every day.

I think we have yet to hear from anyone who has used one of them

[N.C.]

Re question 4: http://www.headalignment.com/

another shiny toy.

[Russwinters]

I haven't used it yet (still waiting for our demo unit), but I have seen Mr. Kotar give us a demonstration using a 750GB drive, and it 100% works. I wouldn't go as far to say it is "easy", but it was much easier then I was expecting. Of course as the developer Mr. Kotar has had understandably a lot of practice using the device, so he will likely make it look easy.

He stated that his team is confident it will work on any size WD (except for the older series where the alignment issue is somewhat different).


My employer, Ji2 inc will be the international reseller for his product; Kotar is working with another reseller for specific parts of Europe (He is based in Slovenia)

Ji2 will be making the official press release in the next few weeks; and the unit will be available from us soon after. We will also be providing optional (but recommended) training with the product in the next few months.

I cannot answer any other questions at this time, but since the "cat is out of the bag" I thought it would be a good idea to make a comment.

Regards,

[drc]

I haven't used it yet (still waiting for our demo unit), but I have seen Mr. Kotar give us a demonstration using a 750GB drive, and it 100% works. I wouldn't go as far to say it is "easy", but it was much easier then I was expecting.

When you say "works", do you mean that a drive had heads changed, then did not init, then he fiddled with the knobs, then it did init and could read on all heads?

[Russwinters]

For this demonstration he had un-aligned the heads previously, the original heads.

Then he re-aligned the heads using the tool.


Reason was that for the demonstration we could not take everyone into our clean room, so we had to perform the demonstration outside of clean environment.

He has full confidence in his tool; they use it in their recovery lab with over 90% success rate on all drives needing realignment; as of my last speaking with him the largest drive they have had to do alignment on was a 2TB Green, which was successful.

I will have the tool in my hands soon, and have quite a few drives that need new heads and alignment, so I will of course let everyone know the results; I will need to practice with the tool a little first before doing some real drives though.

[drc]

Hmm. In my experience it isn't getting the drive to work with its own heads that is the hard part... But I am interested to hear how it turns out for you

[BlackST]

Agree. The problem comes out when you use DONOR heads. It's always a PITA.

[quasimodo]

yes, the trick of course is to make the drive work with donor heads
when you said he unaligned the heads, can you specify what you mean by that, since drives can be misaligned at various points in various ways.Well it sounds interesting, at least if "Ji2 inc" is looking to add it to it's product line, it will receive some credibility.

[Russwinters]

The drive was pre mis-aligned, at the time I did not inquire into the specifics of the misalignment.

We spoke about micro-jog, which is something that this tool cannot combat 100%. From my understanding is that with this tool you *shouldn't* have to deal with micro-jog typically, but maybe you can have very bad luck with you donor heads and their micro-jog is vastly different from the original heads.

The most interesting part was watching Atola's media scan, which reads every sectors response time in ms, in real time, like a graph. Using this once you can get the HDD to ID, you can clearly see the effect that the micrometer adjustments are having on the response times for sectors; giving you a slightly clearer picture on how much certain adjustments directly effect the drives performance, and using the tool it was quite easy to cause the drive to return to mis-alignment while watching this graph, and going too far on a certain adjustment.

All of this being said, I don't think Mr. Kotar would have visited us personally here in California, all the way from Slovenia; to claim that his tool works, when it does not. He came to us genuinely, and with 100% confidence in his system. His team has been using it in their lab for many months now to great effect, which is why he felt it was ready for "prime time".

So while I have not seen it work in a "Real Case" yet; I still have great confidence in the talent of Mr. Kotar and his team, and am anxiously awaiting our demo unit so that I can see some real life results myself.

I promise to keep everyone updated on the real world performance of this tool, and I am confident that I will return with great results. Look for more in the coming weeks!

Exact specifications, kit contents, and pricing will become available through www.hdd.ji2.com in the coming weeks as well. So keep an eye on that.

Regards,

[guru]

If I could show you my new shiny tool you would all pee yourself , sadly I can't :O(


Ji2 inc is an OK company when it comes to electronics but I would not sing from the hills for their recovery skills or experience IMHO from my own personal experience.

[BlackST]

To add some pepper, I am ............... [CENSORED] ......working on........... [CENSORED].........

(Who has to know, knows)



Anyway I want to see it at work, maybe in combination with other method it's worth.

[petkus]

Interesting. Seems more of these are popping up every day.

Must admit thou it looks shinier than mine.

[jono-ats]

In my experience, WD Royal drives with large capacities don't need special re-alignment measures. Is anyone else having head swap problems with them?

However, with smaller capacity drives, such as the Sabre, Mammoth, Hawk, etc., alignment is critical and that is why we initially developed our own adjustment tool. We eventually figured out a way to dispense with using it.

So is this a tool that "works" with larger capacity drives (IMHO that don't seem to need special treatment) but does not work with the drives that really need it? I'm confused . . .

[quasimodo]

@ Jono-ats,

there was a Rap song back in the days. Let me think, what was the name of it again.... Ohh yes, now I remeber. Don't believe the hype!

[BlackST]

by PUBLIC ENEMY... 1987...

[Russwinters]

I will have to confirm, but I believe the only drives it doesn't work with are drives made pre ~2000.

[petkus]

by PUBLIC ENEMY... 1987...

...second album...1988...sorry for correcting you... i am still a big fan

Yes some Royals in my case can be great for 5 min demonstration you could tighten a bit to lose alignment then blow into screw like real magician... release and wola alignment is found.
But then again smaller capacity drives can be quite nerve-wracking. My disclaimer is: Not for impatient people!

[reymuybien]

Anyone has tried the headalignment tool already ?
Any success ?

I'm looking forward to this thread to be updated!