Magnets from Hard Drives...

[Art Mulder]

This is not exactly woodworking, so I wasn't sure which sub-forum to put it in.


Magnets are cool, and fun, and very useful around the home and shop. Lots of us use rare earth magnets in many projects.


I have magnets in my featherboards. I use magnets when changing my DC bag to help hold things in place. We use magnets to hold notes to the door, and so on and so on...


What you may not know, is that computer hard drives (aka: hard disks, or HDs) contain two powerful magnets.


Here is a quick and simple photo essay on destroying old HDs to salvage the magnets in them.


Start with an old or broken HD that is destined for the recycling bin.


I am fortunate in that I work at a university and have access to a whole bunch of old HD's that are being scrapped and tossed into the recycling bin. These are 10+ year old units, either too old, too broken, or too small for continued use.



Peel back all the stickers, and then remove all the torx screws. There are TEN holding this HD closed. They really don't want you getting in there. (And of course normally you don't want to get in there, they are sealed to protect your data!!!) Actually 11, there was another one, even smaller than my smallest torx head screwdriver that I had access to:



Fortunately, a bit of brute force prying was enough to rip off the cover. Go ahead and force it. You don't care about this drive anymore, otherwise you would't be taking it apart! There may be a thin bead of silicone (or similar) as a sealant around the edges of the lid holding it down. Hopefully on your drive you won't have to get sou forceful, if you can manage to remove all the screws.



And here is my sample HD with both magnets removed. The read/write arm gets a bit bent. That really can't be helped, as it is most definitely in the way. But it's also very delicate, so it's easy to force out of the way. The upper magnet is on the left. It nicely has 3 mounting holes, that you can use to fasten it to something. The lower magnet is on the right. These always have some form of bent "legs" (for lack of a better term) sticking up. This makes them a bit harder to work with, if you want to incorporate this magnet into another project. Oh well, that's what hacksaws and grinders are good at removing!



Here I made a simple hook with some oak and a peg as a proof of concept, using the top magnet.



It's quite strong. I'm trying to figure out how I could use something like this in a featherboard in the shop. The trick might be the removing of the magnet once it is attached to the cast iron! Not sure if I could replicate those dial-magnets that are on a lot of commercial featherboards



And here is the lower magnet, just hanging on the body of my bandsaw. Note that the magnet isn't actually touching! The shaped legs are holding the magnet at almost 1/4" from the metal of the Bandsaw, and yet it is still strong enough to hold. These particular model of HD's have VERY strong magnets.



Got some more photos on my website, wordsnwood.com/2013/magnets/, but this is the basic idea.


Hope you found it interesting.

[Dave Richards]

Nice.

As to the featherboards for your table saw, you might take a look at the auxilliary blade guard in this video at about 5:00 minutes in. Maybe gives you an idea.

[HANK METZ]

I can think of more uses for magnets in the shop:

• Holding a cutlist or drawing down on the tablesaw front or top for easy reference.

• Checking for hidden ferrous metal screws or nails in “rescued” lumber: it exerts a strong pull over the suspect item.

• Same trick finding wood stud centers behind drywall, it discloses nails or screws behind the mud job.

• The old trick for gathering up fasteners accidentally spilled on the floor: put it inside a plastic bag, sweep over the goods, turn bag right side out, pat yourself on the back for such cleverness.

Probably a whole lot more uses from others…


- Beachside Hank
Improvise, adapt, overcome; the essence of true craftsmanship.

[AL Ursich]

Along the same line, the Disk can be cut to a round disk and used for a replacement for the Front Surface Mirrors in Laser Engravers... I posted a link in the Engravers Forum about 8 months ago. You might consider collecting them you might find a buyer...

AL

[Bill Geibe]

Another of many uses - stick one of the magnets on the front of your drill press to hold the chuck key. Or one on any other machine to hold frequently needed adjustment tools (hex keys on a band saw, for example).

One small word of caution: When handling these super strong rare earth magnets, keep in mind that they can snap together quite forcefully. If your finger is at just the right position, the impact can raise a really nifty blood blister! DAMHIKT!

Bill

[glenn bradley]

Grip-Tite featherboards simply use a cam-lever for relase as seen at the :55 second mark in this video: http://www.rockler.com/product.cfm?p...bSelect=Videos

[Curt Harms]

I used a couple to make a magnetic lamp base and hold wrenches for machines. The magnets in a Western Digital drive were pretty easy to separate from the bracket then it's only about 1/8" thick. The magnet itself is pretty brittle so a little care is in order. As Bill Giebe says, those little suckers are STRONG.

[John McClanahan]

The magnets are glued to the kidney shaped base with what looks like CA glue. After repurposing magnets for uses like these, I have had the magnet break loose from the base a couple of times. So, be careful how / where you use them.

John

[David Epperson]

For those wanting smaller, but equally strong (for the size) there are two very small "steering" magnets in a CD or DVD drive next to the laser diode lens. These are often around 1/4"x1/4"x1/8" and make pretty fair lid latches for small boxes.
The HD magnets can often be removed from the steel backing plates with some sideways pressure (push away from the little locating bumps). But you will lose some magnets doing this, because they are very fragile when unmounted. And the unmounted ones will break quite easily if allowed to snap together without restriction. I've probably got a 2 to 3 pound collection of these.
I have another source for strong magnets as well - Rodless air cylinders. Some of these are completely sealed, and magnetically coupled with matching sets of inside and outside ring magnets.

[Jim Koepke]

I have one mounted on the end of a stick to pick up things that fall in hard to reach places.

As Bill suggested, one is on my drill press for the chuck key to have a home.

There is also one wrapped in paper at my granite slab where there is sand paper mounted for lapping. The magnet picks up the filings to clear the abrasive. The paper keeps the filings from the magnet.

Lots of fun those old HD magnets.

jtk