Using Hard Drive Magnets

[MickS]

I have proved it to myself by using hard drive magnets any buying and using commercial neo's. Hard drive magnets are just as good as bought neo's

If you bother to spend a little extra time pulling hard drives apart you can end up with magnets just as good as bought neo's.

Mind you you need to have a supply of several hundred hard drives (go and talk to your local junk yard people).

Here is how I do it.

It is easy and no fuss and works every time (1 in 20 you might stuff up).

To bend the backing plate use a spanner (shifter) on each end of the backing plate and twist gently.

The backing plate will bend and the magnet stays straight. Lift it gently so as not to damage the nickle coating too much.

I pile the mags onto a metal plate up to the height I want the magnet to end up at.

The magnetism holds the pile nice and firm so no clamps needed.

To see where to cut exactly just sprinkle a few grains of iron filings on top of each magnet pile. You will see a nice straight line which is where you cut them.

Cut each pile with an angle grinder. The thin cutoff discs make it very easy.

They are non magnetic and cutting a 5 high pile stack takes about 20 seconds (never actually timed it but it is quick).

When you have finished you just turn over one half of the pile and hey presto, there is one magnet for your genny.

The mag rotors (dual rotors)shown here have produced 500 watts into 12 volt batteries.

The prop blades are 1.5 metres radius - recycled old wooden stairs.

3 phase 70 turns per coil, 2 in hand 1.00 mm diameter copper wire recycled from microwave transformers.

If you havn't done it yourself, don't knock it until you've tried.

Mick S

[tecker]

10/4 on knocking .Amps is the only real factor and is objective.

[DanB]

those magnets must be getting hot when you grind through them like that - I'd think you'd need to keep them cool.

[tecker]

No doubt If you scribe them pretty deep with a hacksaw or bandsaw or tile cutter they brake clean .

[wooferhound]

The Platters from the hard drives seeam like they would be usefull for something too.

Like a huge mobile maybe . . .

[tecker]

I tried a few as reflectors pulling the center down into a 3" pipe to concave them works good.

[alibro]

I wondered about the heat as well. I have read that if a magnet is heated above 100 degrees centigrade they degrade. It's hard to argue with 500 watts though. When I have collected enough hdd's I will give it a try too.

AliBro

[MickS]

People,

Please LISTEN UP.

I have done this time after time, lost count of how many times.

Have a look at the cutoff disc I showed in the pics. If the graphics were allowed to be better you would see that it is VERY THIN, hence VERY LITTLE HEAT GENERATED, and no noticable after effects so it is not worth stuffing around doing it the hard way.

You do not need any fluids.

If you dont believe go try it for yourself.

Forget about scoring each individual mag.

As I said in the post, pile up as many mags as you need to make the pile as high as you desire , place the pile on a metal surface, the magnetism will hold them without need for any clamps.

Grind away.

Turn over 1 half of the cut pile and you have a magnet with the dimensions of approx 40mm by 20mm by however high you want them to be.

Hope it gets through this time

Mick S

[Gary D]

They (magnet holders) might make nice strikers for wind chimes?

 As for the heat the dremmel creates, possibly the no-mans land between the two poles and the blade thinness allow for most of the heat to dissapate before reaching the actual poles? Without a gauss meter, it's mostly guess work though. Just a thought, wouldn't want to try cutting thicker magnets without coolant though...

[hvirtane]

Really nice job.

Good recycling.

"The prop blades are 1.5 metres radius - recycled old wooden stairs."

Any pictures of the blades available?

- Hannu

[MickS]

Hannu,

This thread is getting a bit long.

I'll start a new one with the pics on the prop blades.

Mick S