I have about 20 hard drives that I need to destroy. None of them will hook up and read, and they’re old enough that I don’t expect any highly sensitive / currently-exploitable data to be on them. But I want to get them to “hard enough to recover that the average person wouldn’t bother”.
Tentative plan at this point is to beat the slop out of them with a hammer. I figure enough case damage, combined with likely shattered platters, should be more than fine for my purposes.
That said, I don’t own a nice heavy bashing hammer, so I was thinking of getting a 3 pound cross peen - but I am open to suggestions.
If those drives are still available for disk utility, the safest way would be a reformatting, with a couple (<3) of passages. The more, the better!
You can select that within the preferences.
It is very hard to destroy a harddrive physically in a way it could not get recovered.
If the datas were not sensitive, have fun with the Hammer…
In theory. But it’s a gamble. Real physical damage to the medium sometimes CAN be PARTIALLY recovered. And often enough, it couldn’t (severe head-crash). But we are talking highly specialized companies and 5/6-figure bills. Nobody who finds a drilled hard drive in the trash will put that many resources into recovering a drive. If you have that kind of enemies, put a hard drive shredder in your safe room. That’s why I like the “stick drive into gap and step on it”-method. Completely bent/shattered platters.
BTW: for a magazine, they bought ~100 hard drives (eBay, resellers,…). And could restore a lot of data, including sensitive company data. Often enough, just formatted. I think it was the German magazine c’t.
It’s a kind of a technical science, and it is working in almost every case, where there is no severe physical damage for the single disk itself (not the HDD-Case!).
With a severe Headcrash e.g. you are only loosing the date that lies within the area where the head (if at all!) had scratched or pierced the disk. All other areas could normally been read out.
The biggest issue on the data recovery is, to get the read out data back in order to regain the single files. So depending on what areas are damaged, it could be easier, or more difficult, but the chance to get some Data back is somewhere between 90-100% for all areas not physical damaged on the disk itself.
And the cost range between a few hundred, and a few thousand $/€.
The easiest way to erase data from an HDD is formatting in a “safe erase way”. For this the whole Disk is filled several times (Minimum 3) with random data (Numbers, Symbols, some Systems use Pictures or Movie-Files, and so on), or you are using the “Gutmann method” with 35 passes of Data with a specific pattern of random and specific data.
If an erase is done like this, it is highly unlikely to reconstruct the data in a laboratory.
Only “formatting” is not changing any data, but just removes the “table of content”, while all data are still at the same place, and could be readout with cheap, or even free, programs.
An other method of a safe deletion of an HDD might be a strong Magnet, but it has to be more likely the one that is lifting cars on the Scrapyard, as the one we usual have hanging around on the fridge, or the white board.
And the magnet should be placed on the HDD several times, in several directions.
Also this method is often seen on movies, and also sometimes sold by “security companies”, it is not a method that could guarantee a safe erase, if it is not done probably!
You can also shred the HDD into very small pieces, or heat it with a temperature of more than (as far as I know!) more than 700°C.
Ohh, and by the way:
If you have a HDD with some damaged sectors (and otherwise “normal values”!), you can often recover the HDD (NOT the Data on it!!) by a safe erase with at least 3 runs using the Disk utility of macOS, as the damaged sectors are isolated by the system.
Unfortunately I don’t have an appropriate drill, and cost is part of the issue - but yeah, I can see this being an awesome way to fly! I’ll definitely look into options and see if it’s as cost-prohibitive as I’m thinking.
I’m imagining walking into the local tool shop asking for one of those. “No, that’s not a left-handed one. Don’t you know anything?!?!?! Can I talk to your manager?”
Yeah, that’s the rub - they’re all 3.5".
Yeah, if the CIA or NSA are after you, requirements ramp up considerably. In this case, if they recovered all the data on these drives they might have some old bank statements for an account that doesn’t exist anymore and my old music / music video collection, along with some business invoices and Photoshop assets.
Stuff I wouldn’t just hand some guy off the street, but stuff that somebody who was invested enough to actually go after recovering data from a hard drive with shattered / damaged platters would be able to find some other way, almost assuredly.
"Today on the channel we’re doing data destruction on a hard drive. You can get some software utilities to do this, but if the drive isn’t readable the only option is to physically destroy the drive itself. And the best way to do that is with fire - about 5778 Kelvin.
You should note before doing this at home that shooting metals and rare earth magnets into the sun could ever so slightly adjust the gravitational fields in our solar system, so you’ll need an easy-to-get permit from NASA if you want to try this at home. Link to the permit in the comments below.
Be sure to mash the ‘subscribe’ button so you can stay tuned for updates over the next year or two while we wait for the drives to meet their fiery demise."