When disposing of an old hard disk, it might be tempting to simply throw it in the garbage, or sell it. However, first you should remove any sensitive data from the disk. This might be financial data, old email, login information for web sites, and the like. Unfortunately, simply deleting files doesn't normally remove the data -- it just marks the space as available and removes the file from the directory listing. The data can be recovered at this point, often quite trivially. If you wish to protect your data, you need to do something more thorough. There are some software utilities that can do a fairly good job, but if you're feeling especially paranoid (or simply want to have fun!), a physical process is required.
Please note that casting is a potentially hazardous activity. Observe appropriate safety precautions. The details should be covered in whatever casting training you received, whether online or in a class.
In this instructable, we'll erase the disk by melting it. Hard disks are mostly made of aluminum, which can be recycled, so don't throw it out! Instead, we'll cast a new solid-aluminum hard disk using the original as a pattern. For this project, we'll use the aluminum foundry at TechShop Raleigh-Durham. That way we have all the casting tools we need, including sand, furnace, flasks, and molding tools.
Please note that casting is a potentially hazardous activity. Observe appropriate safety precautions. The details should be covered in whatever casting training you received, whether online or in a class.
In this instructable, we'll erase the disk by melting it. Hard disks are mostly made of aluminum, which can be recycled, so don't throw it out! Instead, we'll cast a new solid-aluminum hard disk using the original as a pattern. For this project, we'll use the aluminum foundry at TechShop Raleigh-Durham. That way we have all the casting tools we need, including sand, furnace, flasks, and molding tools.
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The first step in any casting project is to prepare the casting sand. Start by sifting the sand to remove debris and break up clumps. Then add water to temper the sand so that it sticks together. Add enough water to make the sand slightly moist, but not wet. It should clump when you squeeze it in your hands, and break cleanly rather than crumbling when you break it. If you add too much water the sand will get sticky, and stick to both the tools and your pattern, making it difficult to work with. The additional water will also generate more steam, which can interfere with the quality of the casting.
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I use http://www.dban.org/ to accomplish the job. It's free and removes everything.
I am not trying to be negative. NO never. The best way to discard an old HDD is to open it up, remove the shiny platters (can be used as Sun reflectors) remove the Neodymium powerful magnets and send the Aluminium cast body for recycling. The end.
However, the neodynum-Magnets from HDDs ARE a nice thing to have for all kinds of things.
There are a lot of cool instructables who involve magnets. Here you have a free source of really powerfull ones. :)
Why? Because the platters are calibrated to the read/write heads during a low-level format that's generally done at the factory. This format becomes a type of fingerprint, making the pairing unique (not to be confused with an operating system format (which lays down the O/S specific file system). If one were to transfer the platters from one hard drive housing to another, or replace the read/write head assembly, they could have fun doing a low-level format (given the proper utility). Attempting to read old data off the new platter/head pairing would be like trying to decode the static that radio telescopes receive.
Contact Seagate. They make the stuff. And they'll tell you the same thing.
If the platters as it arent physically destroyed and the metallic structure of the platters isnt physically rearranges (like with melting & grinding) you ALWAYS can get to the data.
It may take an electron-tunneling-microscope (to generate an optical representation of the magnetical topography) of all platters which is EXTREMELY costly (we talk in the 100'000s of $). Later you can then rebuild the complete data using this magnetical topography even if you only have the platters without the pickups.
However, if you have the platters in good condition, you can reinsert new pickups and do whats called a sequential sweep:
You go trough all possible adjustments of the pickups (normally around 1-10 mio) and read a known portion of the disk. Every disk has this. And if it at least the preload of the TOC and MBR. Those few bytes are ALWAYS known regardless of the format of the Data itself. Now you just look for a configuration-set which yield those known bytes from the known location. If you have those, you make a complete read of the platters as Raw-Data. Then you analyze the data and decide if that was the correct adjustment for the pickups or not. If not, you look for the next configuration which gives you the correct preload-bytes.
This "look for conf to get correct preload and make a Raw-read" is often automatic and you end up with maybe 100 Raw-dumps to wade trough...
Cheaper than the tunneling-microscope. ;)
And in a nutshell: Ripping and destroying the configuration of (or the pickups itself) does NOT make the data unreadable. Thats an urban myth. It simply makes it harder (Laborwhise and moneywhise) to read the data.
Yes, there are some fake recycling programs where no actual recycling happens, and all your work of setting recyclables separate from trash is ignored, and it all goes into a landfill.
At the other extreme, there are recycling programs where the resident throws everything in one bin, and it's sent to a facility which separates everything, with metals, glass, plastics, paper, etc, each going to separate destinations... and little or none of it going to a landfill.
So you have to strip the harddisk from the PCB and motor first?
At least the motor has a lot of another metal in it, right? Doesnt this make some sort of Copper-Aluminum-Iron-Alloy then afterwards??
Steel and stainless survive unscathed (you can make hot metal tools out of them). Lead will dissolve in trace amounts, but there probably wasn't any lead here - modern solder is lead free. I don't know what the tin does, but almost anything that melts will dissolve at that low a concentration.
Copper in the wiring won't melt, since the aluminum is below the melting point of copper. However, the aluminum dissolves the copper, similar to water dissolving eg salt. I didn't find any copper pieces after the pour. The same goes for the rare earth magnets; they seem to have dissolved as well.
And yes, this makes this some alloy of unknown composition, but that's what it would be anyway. Copper, zinc, magnesium, and silicon are all common alloying agents in aluminum. There was certainly some zinc and magnesium in this pour, based on what I know was included in the scrap. Probably some silicon; copper was possible. Also, the steel crucible adds trace iron contamination. Iron is not a useful alloying agent, but also doesn't hurt much at the typical trace level.
I'm no expert, but to my understanding:
Of all the metals commonly found in a HDD, the aluminum and lead will have the lowest melting points, with copper/iron/the others being notably higher. Assuming you don't run the foundry too hot, you should be able to melt the aluminum (and lead) out, and be left with the other components in a solid form (the PCB and some of its components will burn up though). The lead and aluminum should be easy to separate, as they have different densities and one will float on the other. (fun fact; steel floats on molten copper)
Assuming you do run your furnace hot enough to melt everything (and burn off that which does not melt), separating out the different metals shouldn't be too difficult as, once again, they have different densities, so they should naturally want to separate out. (like oil on water)
no coffee today
This is actually just an instruct-able about casting. A lovely one at that, hiding the information between the more interesting guise of "recycling the harddrive." Everyone knows it's reuse before recycle anyway, and that Alu melting takes a ton of energy.
Didn't think that alert was necessary until I read the first several comments below :p. I was going to just leave it at something to the likes of "thanks! Cool instructable."
A power drill or a sledge hammer does the job faster.
http://news.bbc.co.uk/2/hi/programmes/real_story/4791167.stm
I make small sculptures and jewellery etc...
EvanBD is totally on the money about the level of moisture needed in the sand to be correct... The finer the sand and level of detail you want, the more critical the water level is.
....to the point that some days you wish you had just stayed in bed because you keep getting deformed results. :o)
I have included a photo of one of my castings, and no bits and bytes were hurt in the process. There was a small amount of swearing during the process though. haha
On the data side of things, which to be honest, that is NOT what this instructable is about - get a grip people!! It's about casting...
But anyhow...
I know that you can get data back from multiple erased disks etc... so I am not arguing with that.
Standard "Department of Defence- DOD" practice is to multiple erase with random data, grind disc platter down to a fine powder and then mix in with cement for foundations of the next building.
All that aside, from my previous 15 years of experience in the tech industry, it amuses me to no end, the amount of paranoia and self importance people have.
The paranoia level is usually way too high, and that is perfectly matched with a level of self importance that is way higher than it should be.
Yeah, I am sure someone is going to want to employ DOD level of hard drive forensics because they want to find out what you wrote on your English assignment 20 years ago that just happens to be on your hard drive to this day.
Have you thought about the fact that it would be many times easier for some criminal to put a sack over your head, throw you in the back of a van in the morning as you walk out your front door, clip off your little finger with a pair of bolt cutters and then say, "Tell me your bank details, credit card info and passwords or we start working our way up in finger size". The whole process would take around 10 min and reveal a lot more valuable information.
Also try not to sacrifice the environment with waste and chemicals for the need to destroy that year 11 English assignment in a subdirectory on your harddrive...
:o)
Marty
http://www.computerworld.com/s/article/9083718/Shuttle_i_Columbia_s_i_hard_drive_data_recovered_from_crash_site_
I would like to point out this hard drive fell from freaking space and they still were able to get 99% of the data off it.
Thus short of completely destroying the entire disk data with always be recoverable regardless of what BS software you want to use.
It does not matter if you run 1 wipe or 900 wipes if you have enough time and money you can get the data.
Time and money being the key point here.No one gives a damn about your crap data.No one cares that you banked on your computer.If you run just a simple program like Kill Disk 1 time your fine.If your worried about your data that much take a part the whole thing and break it with a normal hammer. Problem solved.
In conclusion no software can EVER FULLY remove any chances of data recovery.Can it make it so unlikely as to be pointless ?Yes does anyone care enough to even try to recover your worthless data ? NO.
There are also smaller ones that automatically punch large diameter holes in the drive. My low tech soluton is a 6 foot concrete breaking spike which will make short work of any platter! :)
I'm not trolling, I just don't know the answer and I'm curious.
TIA ;-)
The DoD 5220.22-M spec is to write random 1s and 0s to every sector of the drive seven times, which does a decent job of making the data unrecoverable. The current spec for drives that have held classified information doesn't allow for anything other than degaussing and destruction of the media, though.
http://en.wikipedia.org/wiki/Data_remanence
This instructable is Overkill in every sense of the word. I guess the author has too much time on his hands.
Again WOW!
It's quick and doesn't involve sand.
the platters got a date written on them with a sharpie, and I used the magnets to stick them to the side of a steel file cabinet next to the phone in the computer room. Whenever I was on hold with tech support, i would rearrange the magnets on the disks on filing cabinet. After a few months of this treatment. (that's why I wrote the date on the platters) I would take the data platters to the rifle range and using some string, hang then platters from the target frames. Then shoot at them, and encourage all the other shooters that happen to be there to shoot at them. End result, a twisted perforated piece of metal that goes into the metal recycling bin.
At my current job, we have a sandblasting cabinet. I'm considering sandblasting the oxide layer off the disks as an alternative.
-Olaf
http://youtu.be/sQYPCPB1g3o
As does this:
http://www.instructables.com/community/Thermite-Destruction-of-Hard-Drive/
(man shred:
SHRED(1) User Commands SHRED(1)
NAME
shred - overwrite a file to hide its contents, and optionally
delete it
SYNOPSIS
shred [OPTION]... FILE...
DESCRIPTION
Overwrite the specified FILE(s) repeatedly, in order to make
it harder for even very expensive hardware probing to recover
the data. )
(it's a standard GNU/Linux command)
1) Disassemble it.
2) Remove and save the magnet, which can be reused for projects.
3) Remove the drive platters.
4) Physically abrade the surface of the drive platters with
sandpaper, emery cloth, or a rotary sander.
5) Break apart the logic board with pliers.
6) Recycle all the scrap metal.
Even a forensic lab wouldn't be able to recover any useful data.
The electronics printed circuit boards should be removed, the FR4 epoxy fiberglass board material is designed not to burn easily and is toxic under high temperature. There is also usually two rare earth magnets which can be put to interesting uses, as well as bearings and a spindle motor and other interesting mechanical parts, plus screws which usually require special bits - Techshop has these on the shelf.
So remember only the platters (round disks) need to be destroyed that is where the data is stored. The frame of the disk drive is usually a aluminum alloy and can be melted down, but all the rest of the drive can be put to better uses, just put them on the binwall at Techshop.
Happy Casting!!!
I type more slowly now, after carrying the magnet too near a metal pipe. Small finger on right hand broke and is permanently bent at the end joint toward my thumb. (This occurred while demonstrating the dangers of super magnets to my research class. I felt more stupid than pain - until the next day when the pain kicked it.)
If you can find it, a bulk VHS eraser does the job quickly and completely (and safely).
Yes, I realize that the topic isn't data security - its all in fun... Unfortunately - the finger story is true...
You can see what i create with them on my facebook, claudia Bijoutia. fiorentino.
After i used it no need to protect it! ahahahahhaah
have a good day!
i can also make a necklace for you with your old hard disk
claudia B, bijoutia, e-artiste
he then proceeds to pour it into a mold, so its recycling in a way
the instructable is more about making a look-a-like HDD from aluminium, its not as much about the "erasing data" part :P (thats just 1 sentence: melt the sucker down!)
/rant
Very cool!