Had a 200gb Maxtor come in. The drive calibrated, and would actually image very fast for about 2 minutes. Then it would start running into occasional errors, that became more and more frequent, until it just bogged down and moved along at a snail's pace. It would get to a point where it sounded like the heads had landed on the platter, this high pitch shrill sound. I would immediately shut the drive off, wait for about 10 minutes, and then start imaging again. It would start imaging, but just very very slowly until it finally stopped and once again made that high pitch sound.

If I let the drive sit for hours, I could go back to it, and once again it would image really fast for about 2 hours. Even if I deactivated certain heads, it didn't matter which heads I deactivated, it still had the same issue. I hooked up a couple of case fans to try and keep the drive cool, since I was fairly confident it was a heat issue. The fans helped a little, but not much. The drive would be fine until it got hot.

I relayed the info to the customer, told him it may take a week or more at this pace to image the drive. He said he needed the data within a couple of days, or he was just going to have to rebuild everything. So, I thought about it, and I wrapped the drive in 2 antistatic bags, and 2 ziplock bags. I threw it into the freezer for about an hour, just enough to chill it. While it was in there, I turned the A/C down as low as it would go, and hooked up 2 bigger case fans to the power unit of my DDI machine. Took the drive out, hooked it up, and started imaging right away. I was able to image the entire drive without a single error this time.

Trust me, I'm not trying to promote the "freezer method" or anything because I do not believe it works in the way most people expect, and can only do more harm than good in most cases. I was just at a point where the customer didn't have time for us to try anything else. We didn't even have time to order a good parts drive in order to swap heads. So I really did it on a whim more than anything else, but that little bit of time I chilled the drive, definitely helped.

What's the scientific evidence in all this ? Simple : either motor problem (bearing ?) or something related to thermal dilatation.
You were lucky you had no crash or stiction. What count is the result, but it's no science, it's empyrical. And I don't count on luck, only on my skill.

What would I have done, instead :

1) measure RPM and see if it varies when drive heats up. You can even do it without opening the drive !!
2) check the SMART logs when drive is cool. There's a lot of info about flying height and so on. Obviously you have to decode them
3) check if the behaviour when reading is the same at different location. Review your physics...
3) then decide what to do.

This is science. Real gurus here KNOW. And don't ask me anything, I know NOTHING.

I'll be the first to admit it was pure luck. Unfortunately time was of the essence, and it was either try that, or just forget the job, because the customer had no time to wait. I just happened to be lucky that it worked. Different positioning (i.e. on it's side, upside down, standing on it's end) had no effect.

Some drives definitely do better when imaged cold.

The "freezer" trick has risk. You can certainly kill a drive with it. But sometimes it works really well. There are some techniques for reducing the risk of the procedure. It should only be used as a last-ditch approach, and only after you've done everything else competently and correctly. I cringe when clients bring me a drive they have frozen; I am certain that they have not taken the precautions that I do. Like I said, I rarely try it -- it's too risky.

Why does it work? Adaptives can change. Changing temperature changes some of the parameters.

Kudos to the Italian Stallion for trying to use a scientific, empirical approach. However, for the sake of "intellectual argument" (i.e, do not read any of the following as recommendations), suppose:

1. You measure RPM and find it to be wrong. You change the PCB. That doesn't get it. So then you have to do a platter swap with the attendant risks. Which is easier . . . freezer or platter swap? Which is more risky?

2. SMART log shows problems with flight height. How do you change that . . . unless you've spent countless hours doing experimenting and reverse-engineering? Which is faster . . . freezer or R&D?

I'm not sure I understand what is meant by measuring behavior at different locations.

If BlackST has the wherewithal to safely change the adaptive parameters of any drive sent in for data recovery, though firmware, software, or hardware manipulation, I shall be the first to build a temple to the Supreme Guru of data recovery . . .

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Yes Jon, I don't want ANYONE to misunderstand this. This was kind of a "hail mary" given the strict time constraints I was under. I had swapped boards, and had done whatever could be done, checked adaptives within PC3K, tried imaging with various heads deactivated, tried having the drive in different positions, added fans to try and cool the drive. Adding the fans is the only thing that made even the slightest difference. The common denominator in all of the attempts was the temperature. I never, and when I say never, I mean I NEVER even consider putting a drive in the freezer. I've used component freeze on some drives when a board gets hot, but this is the first time I've ever seriously considered putting a drive in the freezer. Even then, I only put it in for an hour, just to chill it really. I was not expecting it to work to be quite honest, because I felt that even though I had the drive sealed up really well, there was a very very good chance that condensation would still build up on the platters. It was just luck that it even worked.

why didnt you just change the pcb?

Of course freezer is fast than r&d. You can measure rpm by checking and comparing pulses on pcb, especially on Maxtor calypso or sabre. About logs, only some study is required. Finally, if you want to force adaptives, is even easier. I started posting on this forum in 1996 when I was studying selfscan and adaptives on Maxtor... And still playing with them. Note : temp has a role, head current and many other parameters are effectively compensated in real time in RAM and on the mcu according to drive temperature, while overall servo adaptives are recorded on SA. Would be interesting to discover the mechanism inside all this...

I did. No help.

Anyone use tec cold plates?

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Buy your friends Toshiba\Hitachi and your enemies Seagate.

At present only for Maxtor, Samsung and some experiment on Quantum with partial success ( as expected.... ). For WD :

anybody-working-adaptive-tuning-t13139.html

That should still qualify . . . for obeisance to the MASTER!

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Anyway, i know, sometimes the coolness helps the drive to work, this is true.
But the freezer technique is really "amateur" attempt.
You should use any airco's cold air to keep the drive in about 15 °C, instead of freezer....

Janos

I also had a 200gb Maxtor with similar problems and it was only 1 month old!

I guess it might help to cool the drive for up to an hour in the freezer before imaging. I wouldn't leave it any longer!!!! Then once you start to run the drive it will soon reach operating temperature and if faulty the temperature might well start to rise beyond the standard specification.
Anyway I found by using high powered fans to blow air at the drive whilst imaging did the job for me.
I think even better would be to mount an air conditioning unit to blow cold fresh air.

That particular drive I successfully imaged would at times make a horrible squeeling sound and there was a smell of oil just like you might find in a mechanical engineering workshop.

Never even dreamed of putting a drive in a freezer. There are simply far more elegant, controlled, professional ways to achieve such a result...using commonly available materials and substances. Even a broke bum could afford as well as perform such a technique without resorting to the freezer technique.

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I find it funny some people are so smart, but lack the basic ability to actually read and comprehend what was posted. While your sitting on your elegant high-horse it might be worth repeating that this was a do or die effort, that I literally only had a couple of hours to do. Do I put drives in the freezer and expect to recover them? Hell no! The only reason I even posted it here, is because I was actually surprised it helped. Knowing how drives function in regards to temperature variances I couldn't believe it helped. Regardless of what you may think, and as much as I DESPISE the concept, it DID help. I had a temperature problem, I needed an IMMEDIATE resolution, I put a drive in an ice cold environment for about an hour to bring the temp down quickly and this allowed me to image the drive. **GASP** I can think of at least two cases where even the gurus at ACE have suggested I throw a drive in the freezer when it gave me similar issues, but I never did because I had more time to work with those drives in a more "elegant" and "professional" manner. I consider the people I deal with over at ACE, as being both knowledgeable and professional for the most part.

I didn't have time to go buy a bunch of crap to experiment with. The customer either needed his data right away, or he was going to rebuild it, so we had nothing to lose and everything to gain if it could be recovered within a couple of hours. I wasn't going to go out and buy an extra air conditioner just for this job. Do I know things I would try in case this ever happened in the future? Absolutely! Did I try EVERYTHING at my disposal given the time alloted to avoid taking this step. Absolutely! If I had a week, it would have imaged just fine without resorting to this. Did I get lucky? Absolutely! If I could go back in time would I not put the drive in the freezer? Hell no, because now I'm getting paid for a full recovery that I otherwise would not have.

Sorry, but I wan't refering to YOU or YOUR post...just read the title and the last few posts before mine. You ARE right---Apparently I DO lack the ability to read and comprehend. It's tough for me to see how you could think I was talking to or about you without "attempting" to read the whole thread... I was talking about myself. There are an infinite ways to attack a particular problem. I find each persons approach revealing in it's own right. It says a great deal about the individual. Since you were so offended, I had to go back and read this entire thread to figure out why someone who made a discovery and saved his client's data was so hurt by my post.

I said that I never thought about it....I often have "do or die" EMERGENCY cases. If I am not equipped to deal with a TRUE "mission critical" or "do or die" situation, I direct the case to a better-equipped or better experience pro than myself (I don't claim to have all and know all). But I certainly don't take chances, etc with important data. I'm sure that is hardly the comment or reaction you'd expect from someone on a "high horse". Either way, my intention was to spark some ingenuity or creativity from all with regard to the subject.

Furthermore, the "broke bum" comment is meant to stimulate all readers' brains to ask themselves what I might be thinking of that is so cheap and so common and so effective. (An air conditioner is more than .50 per pound, so that's no the answer, BTW).

Just my $.02

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There is little doubt in my mind that cold can have a positive effect on a drive. In fact, I have freed stuck spindles with cold before. Not in a freezer, however. I tend to be rather extreme in my approaches, but that is probably due to my chemical engineering background, which is also why I can't read so well.

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Hi gtd4242,

Fooled by randomness - you should read the book.

Read it 6 years ago. Doesn't apply here, since I acknowledged that I got lucky. However, it's not luck that cold does have a positive effect in some cases, just like heat has a positive effect in some cases.

Hmm . . . I guess that makes me the object of your disdain. Oh well.

Just so you know, IMHO the "proper" way to do it is with a Peltier-effect mini-refrigerator. They cost about $100. I have experimented with some crappy designs that failed, so quality is important.

A typical hard drive dissipates about 6 watts during operation. Lets assume about 9 watts to be safe with an imperfect calorimeter. That equates to about 31 BTUH. Not a huge load to dissipate to achieve thermal equilibrium.

According to Wikipedia, "The COP of current commercial thermoelectric refrigerators ranges from 0.3 to 0.6. So that's 15 - 30 watts input. A fridge like the one shown draws about 4.5A at 12 VDC, or 54 watts. Plenty of margin to get the job done. Notice that the one shown has a nice LED for temperature display. Some modification required . . . sure to void the warranty.

Sufficiently elegant for you, sir? Or have you a better idea?

Oh yeah - don't forget the importance of desiccant.

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