Hard Drives (101) - Changing Heads and platters in your hard drive. Recovering data from a faulty hard drive at home.

Recently I have acquired some excellent tools to recover data from hard drives, change heads, platters and some special tools to access hdd firmware directly and copy/change/rewrite it via a serial interface. I have had many successfull recoveries from hard drives that partitions vanished, size reported incorrectly, and tons of bad sectors.. the story changes with head/platter changes

This is an experiment I did to find out how long a good hard drive (one that reads/wirtes and detects in bios/os [it had a few bad sectors it ok though]) can operate without its cover in a normal environmnet. (The enviroment in this case was a normal room with no windows or ventilation at a comfortable temperature and humidity)

Tools used in experiment:
-USB to 2.5" IDE caddy
-HDD Scan for windows V3.1

Expiriment steps.
1. Ran a full surface test of HDD with its cover on. (found a few bads- read50mb/s write 25mb/s)
2. Unplugged hard drive and removed its top cover with extreme caution not to damage internals
3. Plugged hard drive in to caddy and usb
3a - Hard drive spins up and sends correct post to OS
3b - Windwos detects HDD and identifies size corectly
3c - HDD waits for operation
4 - Run a linear surface scan
4a- Test ran for 5 minutes
4b- Surface results OK
5- Run a butterfly surface test ( read LBA-begging then LBA-end; read (LBA-begging)+x then (LBA-end)-x ) where x is incrementing for each step; This makes the head move up and down the disc constantly increasing surface contact.
5- Test ran for apporx 3 minutes
5b- Noise started comming out from heads (partical of dust stuck to head?)
5c- Surface test still running but performance down by %75
5d- Test reached 5 minute mark. Stopped test and head parked.
6- Unplugged HDD from USB
7- Plugged back into
7b- Hard drive spins up and reads initialiaing sectors and fails
7c- Left for 1 minute; HDD did not init and no detec in OS
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At this point i could say that the hard drive lasted 10 minutes with out its cover in a calm un filtered environment.
I would use this experiment as a guideline. Other models and vendors could perform better or worse depedning on technology used and quality of materials.

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The outcome of the experiment
- Do not open a hard drive in a normal environment. The success rate of changing a hard drive head or platter in this type of environment is reduced by %80 and capped to 10minutes(guideline)
- By doing further research it shows that specs as small as 0.5 microns will harm your heads

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Experiment continued without any strict steps or measurments

*After the the HDD did not init properly i started messing about with the heads. They were making a funny noise so i moved them while the drive was trying to init and was spinning(this took very little effort and i did not press on the heads them selves just as close to the actuator as possible)
*They returned to the original positions and actually stopped making a niose.
*The hard drive detected in OS and i could access it.
*I did a speed test and it fell to read 5mb/s and write 0.24/mbs
*I dont know what actually happened here but the drive was very unresponsive and stopped responding after a short period

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Conclusion

As many other sites and people may claim they opened their HDDs in their living room with the fan running and the cats locked away; freezing the hard drive; running the shower for a while to absorb dust (this causes a humidity issue!) its just ... rubbish?! and as i prooved will only work for a short period of time. [Guideline 10 minutes in excessive usage in a still environment]

Allot of these people had nothing to loose though but when it comes to your life long collection of family photos? All your business information, payrol, taxes, invoices? Its not a laughing matter.

So the conclusion is DO NOT OPEN YOUR HARD DRIVE!! ... in a non filtered environmnet! :)

So that means you need to spend thousands to build a class 1 environment... NO!

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Please note that this is a random thought I caught onto to make a cheap and effective clean area. Any professional that will read this might get a heart attack. Data recvoery is more than clean rooms and equipment, it experience.. and its gained by doing stupid things like this :) hehehe....
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Beyond the scope of this expirement lies a cheap and realible way to accomplish this
This is a DIY'ers domain of how to build a clean box/room

What you need is a HEPA filter to trap particles larger than 0.3 microns and most importantly an Ioniser!
HEPA Filter - Very Important to trap little particles on re-filtered air
Ioners - They releases negatively charged atoms that stick to other particles in the air and cause them to drop to the floor. (Ideally youd need a trap to suck this up and refilter the air)

Sounds like some sort of biochemistry lab stuff.. yes thats what it is. But they use massive fans and pumps combined with large multi stage filters in these types of rooms and they usually are at a positive atmosphere to keep leaks out, combined with sensors and oxygen regulators.

If you suffer from alergies then youll be saying, hey! all you need is a mini HEPA filter fan. You can buy these fans as cheap as £25 with 3 stage filters and (Macro Filter, HEPA 0.3Micron Filter and an Ioniser)
I have seen these types of fans sold in baby shops that claim they can filter a 15m2 room 3 times an hour. Also look in ebay, amazon.. Search for HEPA fan
Ideally you want your area to be filtered 15 times an hour.. so DIY'er brains on and time to make a 5m2 box!

--- Good luck and remember you wont find information on how to DIY fix your hard drive on google because its a tightly kept industry secret. There allot of things that can go wrong and you need years of experience and a very sterdy hand---

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Finally - this is what NOT to do...





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