hard drive rare earth magnets

I want to make a serious magnet for locating meteorites. Those two guys on TV have me stirred up. I walk a lot looking for arrowheads, and carrying a
magnet would be an easy thing to do to find small surface ites. Someone has said that dead hard drives have these. Is that true? I need one 3" dia. I can get one that is .5" thick and 3" dia. for about $25. With the hard drive mags, are they round, or would I have to get several and mount on a plate? Got a friend who does computer work, so could save $25.
Steve
Heart surgery pending? Read up and prepare. Learn how to care for a friend. http://cabgbypasssurgery.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 11/06/2010 08:50 AM, Steve B wrote:

The magnet from a 3" hard drive probably spans about 1.5" or so -- so you'd need half a dozen.
You definitely want to intercept a bunch of dead drives on their way to the dumpster -- the magnets aren't the part that gets dead, and the rest of the drive is throw-away (unless you want a bunch of mystery metal as feedstock for some really questionable castings).
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I was buying damaged hard drives from a local computer shop for $.75. There are about ten different configurations for magnet shape, how they are attached to the case and the layouts. Some of the magnets will be have the poles on opposite ends and others may have the poles through the thickness.
I saved magnets from them and use them to hang tools off of benches in my shop. The small hard drive motors are fun to tinker with also. The circuit boards at my local recycling dealer are worth about $1.25/ pound and one board usually weighs about 5 to 8 ounces. The Die cast Aluminum the case is made from is only worth about $.30/ pound. A sharp knife and a good screw driver with various heads are all you need to disassemble the drives. Some of the IBM drives will require a special tool that costs @12.00 at Radio Shack. I can strip one down in about five minutes now but when I first started doing this it could take as long as twenty minutes. It took so long because they are all put together different and figuring out what tool and how may take a while.So I would say if your time is worth anything it will be cheaper to buy your magnets from E-Bay and pay $10 or less. But if you have time to spare it is very interesting tearing these things apart and figuring out different uses for the various parts.
Have fun, DL
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Arrow heads are magnetic?
Then one could really clean up with one of these:
http://www.grainger.com/Grainger/WESTWARD-Rolling-Magnetic-Sweeper-1VTY2
Gunner
--
"Confiscating wealth from those who have earned it, inherited it,
or got lucky is never going to help 'the poor.' Poverty isn't
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nah, just where we look for arrowheads, there are a lot of gravel bars and pockets between the sand dunes exposed by erosion that have some interesting small rocks in them, and a magnet would find one in a second. So, while I'm there, it would take no more time to sweep the area with a strong magnet. I have seen the drag behind huge coil those boys use on Meteorite Men, but they use it on flat plowed Kansas farmland. You need it close to the ground, and that is difficult to maintain unless you have absolutely flat ground, and that isn't anywhere I know. Those guys found one loaded with olivine on a recent show, and computations on the gemstones in it approach $1million. The White Cliffs (Castle) area in NW Arizona has a strewnfield of Martian meteorites, and one as big as a matchbox may bring one million. But looking at them, they look like any other rock to me. They're (IIRC) not highly magnetic.
Steve
Heart surgery pending? Read up and prepare. Learn how to care for a friend. http://cabgbypasssurgery.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Steve, Those magnets are small and not very good for your purpose as they are asymmetrically magnetized. Steve

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

    R2000P 2'' Dia x 2'' Long Rod, Licensed NdFeB, Grade N40 Neodymium Rare Earth Magnet , Ni-Cu-Ni (Silver in Color) Plated, Thickness Magnetized, Poles On Flat Face
Amazingmagnets.com 90 bucks. Warning, this size magnet can be dangerous.
Wes -- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 6 Nov 2010 08:50:18 -0700, "Steve B"

Howzbout one of these? http://www.google.com/search?q=cow+magnet
My sister has a large, blue-plastic coated magnet from her stint at Mercy Hospital (clerical) in Sandy Eggo 3 odd decades ago. I don't think they use them any more. 3.5" dia, 1/2" thick, 1" hole in the center, aqua. Jus gawdjus.
What's with the iron-containing ites, anyway?
-- If we attend continually and promptly to the little that we can do, we shall ere long be surprised to find how little remains that we cannot do. -- Samuel Butler
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I guess some of them have high nickel content, going off for a metal detector, but not being drawn to a magnet.
Steve
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Nickel is magnetic also. -- Boris
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Boris Mohar wrote:

So are some bronze metals too.
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Hard drive magnets are for the seek motor, have a range of a few millimeters. What you want, for exploration, is a magnet with the poles far apart. It matters not at all what the diameter is, you need to specify the spacing of the magnet poles instead. Easier, though, to just use a metal detector.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Easier, though, to just use a metal detector.
I've owned a metal detector since 1980. Swinging one all day is tiring. I do have a White's, but for quick, down and dirty hunting while hunting, I'll see what this magnet will do before I take my metal detector out there and swing it for eight hours.
Steve
Heart surgery pending? Read up and prepare. Learn how to care for a friend. http://cabgbypasssurgery.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Steve B wrote:

Are you talking about dragging the magnet across the ground, in hopes of attracting these magnetic shards, or just using it to check them when you think you've found one?
If you're out hunting for meteorites, you might consider one of those "metal detector" projects. :-)
Have Fun! Rich
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nah, just having something I can swing an inch or so off the ground in gravel banks and flat areas that have eroded gravel in sandy areas. Some areas have black sand, which is ferritic sand, occurring where gold is found. A magnet would get fouled with that stuff real quick. But I'd keep all bigger pieces it picked up to check at home.
Steve
Heart surgery pending? Read up and prepare. Learn how to care for a friend. http://cabgbypasssurgery.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

A little tick to keep your magnet from getting plugged up it to wrap some Saran Wrap around it. When the clump of magnetic material builds up to a certain level just wrap the Saran wrap around it and put it where you want.
DL
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
TwoGuns wrote:

A plastic bag is less messy - when the outside of the bag loads up, reach into it, grab the magnet, and turn the bag inside out, with the schtuff inside it. :-) (that also works with dog poop. ;-)
Cheers! Rich
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gunner Asch wrote:

And how does he keep a dog inside a plastic bag?
--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Michael A. Terrell wrote:

Just in case you guys aren't joking, you use the plastic bag as if it's a glove, THEN turn it inside out, around the poop, with your hand now on the outside.
But you guys aren't _really_ that obtuse, are you?
Thanks, Rich
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rich Grise wrote:

If you have to ask, what does that say about you? :)
--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.