1. Hydrochloric (Muriatic) Acid Burn
This stuff is highly toxic, so you have to be fully prepared to use it and wear all the safety equipment of the day (eye goggles, aci-resistant gloves etc). To destroy your hard drive using this method you will need to pour in a measure of Hydrochloric Acid into a glass cylinder that is deep enough to avoid spilling over once the hard drive is inserted. Tie some wire around your hard drive case and lower it into the acid. Let it sit there for a number of hours so that the acid gets all the way inside the casing and can munch away on yor disk. To really get the reaction going, expose the acid to sunlight. Be warned, once the reaction gets going the acid will start bubbling and may spill over onto the floor. So make sure you are well prepared!
2. Burn It With Thermite
Thermite burns at about 3,000° and is used by the military for thermite grenades, making it an ideal candidate to destroy any hard drive. Once you manage to get your hands on some of this stuff, place about 4 or 5 pounds of it on top of your hard drive. It would be advisable to place the drive on sand so that the surrounding area does not go up in flames. Stand far back and ignite the thermite. Once you are satisfied that the drive has been irreparable destroyed, douse the flames in sand or water.
3. Smash It With A Hammer And Hacksaw
This way is a little less corrosive or explosive, but it will still destroy your hard drive. It also means that you don’t need to worry about where you’ll get some acid or thermite, just have a look in your garage. First off, take a large hammer and start to whack the hard drive repeatedly until you see plenty of damage. Ideally part will be falling out at this stage, if they aren’t give it a few more solid whacks. Then clamp the hammered hard drive tight with a vice. Now take your hacksaw and start to saw the hard drive into fine strips, making sure to wreck the discs and platters. Once done nobody will get a thing off it.
4. Grind It To Powder
This is another simple way of totally destroying your hard drive, making it impossible for even the best of data recovery services to recovery a single byte. Take your hard drive and place it into a vice, then clamp securely. This clamp should be attched to a large study workdesk that won’t move. Then take a grinder with a large 60 grit sanding disk and go to work on the hard drive. Your aim should be to reduce the hard drive to a pile of powder, just like something you’d see your mum grinding in a mortar and pestle.
5. Fully Bork It With Magnetic Degaussing
Finding magnets powerful enough to magnetically degauss your hard drive will be a bit of a challenge, but it is a foolproof way of destroying any and all data on your hard drive. Once you get your magnets together, lay them out on a surface and pass your hard drive over them. Rub them back and forward, left and right, alternating exposure to the magnets.
If you f**k up trying this.. don't blame me. Do this at your own risk.

