The first time I took apart a hard drive I was amazed by the super strong magnets inside. They were mounted on steel plates with holes already drilled in them, just waiting to be re-purposed. Here's a few ways I've used these magnets on my workbench.
Step 1: A Simple Light Duty Magnetic Clamp
All hard drives have two strong magnets with a pivoting coil sandwiched between them. These magnets come in various styles. For a bench clamp, I selected a set of magnets that pivoted on a slot and groove. This allows the magnet to accept a wider variety of material sizes without slipping. I mounted one magnet to the edge of the workbench with screws. The other magnet could then be slotted over it and used to clamp items firmly. It can hold circuit boards, larger spring clamps, measuring devices and other small items.
Step 2: A DIY Helping Hand
The magnetic clamp is really handy as a helping hand. I attached an alligator clip to either end of a twelve inch piece of heavy copper wire. When the wire is folded in half and clamped in the magnets it can be used to hold a circuit board, pair of wires or other items while their being soldered. For heavier work I use two alligator clips mounted on lengths of bamboo skewer as it is stiff and can be easily cut to any length needed.
Step 3: A Magnetic Tool Holder
I selected another set of magnets for the other side of the bench. This set didn't slot together, but one side had 'ears' that stuck out the side. I mounted this one to the front corner edge of my bench. It's very handy for holding tools, keeping wires out of the way or hanging my drill motor.
Step 4: A Screw and Hardware Holder
I mounted the flat magnet to the top of my workbench in the corner near the tool holder. This is handy as a bench dog and it's also a handy way to keep screws in one place when I'm taking something apart.
There are many more uses for dead hard drives and their magnets and I'll be covering a few more over the next few days. Go grab a dead computer and have some fun!