Where to get rare earth magnets?

I'm not brewing this weekend, so I figure I may try to make my stirplate. Where did everyone go to get their rare earth magnets?

Old computer hard drive...

Yup i have seen them on ebay, but they are free fron the old HDD. Be careful whacking them off (did i say that?). I broke one taking it off.

I wish we didn't toss our old computer at work recently. Where in the hard drive are they?

Try this... http://cgi.ebay.com/4-Rare-Earth-Ne...yZ119113QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Canadian source www.leevalleytools.com

Oedipus Rex said:

Try this... http://cgi.ebay.com/4-Rare-Earth-Neodymium-Magnet-1-x-1-4-x-1-4-Ring-N48_W0QQitemZ130172307044QQihZ003QQcategoryZ119113QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Click to expand...

Over $20 shipped just for the magnets for a stir plate? that's way more than you need to spend, you could build a whole stir plate for that much. If you're going to buy magnets online, at least look for something cheaper - you can get smaller rare earth magnets on ebay for like $4 shipped for a bunch of them.
http://cgi.ebay.com/Rare-Earth-Disc-Magnet-7-16-Neodymium-Very-Strong_W0QQitemZ230192286583QQihZ013QQcategoryZ119113QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Hacking them from a hard drive is much cheaper, if you can't get one from a friend, try a small computer repair place and see if they've got any junk drives destined for the trash. Just open up the drive (may involve drilling out some screws if you don't have fancy security bits to remove them), tear things apart enough to extract the plates with the magnets on them, and then separate the magnets from the plates. To do that, take a knife or metal scraper or similar, and gently tap it between the magnet and plate with a hammer, until they separate.

Hard drive magnets work great because when you stick two of them side by side they're about the right size to fit very well on the fan hub, so it's very easy to get them centered and you only need a small amount of tape or glue to make sure they stay in place.

I took apart six hard drives. I have this huge stack of metal squiggly things with magnets adhered to them, but not a single one comes of the big metal piece and it's too big to use on the stirplate.

I went to a local hobby store and they had them so I got a handful.

Hard drive. Purchased some magnets from http://www.sciplus.com, but they weren't strong enough.

www.unitednuclear.com

not sure what you need but if it needs to be really powerfull they sell them here under general science.

A good way to remove the magnets off their plates is to grab either end of that plate (NOT THE MAGNET!) with some vise grips or lock one end into a vise and twist the plate. The magnet pops right off the plate and you can use a paint scraper to pry it away. I broke a few of them using the hammer tap method. An acetone bath works to dissolve the glue as well.

Thanks, I was using this method.

Professor, if you're down this way, Science Safari at Saltbox Village in Cary has rare earth magnets. Saltbox Village is near the Trader Joes at Kildaire Farm Rd. & Cary Parkway but a little farther north on Kildaire Farm toward Maynard.

Chad

Castle Meadow Brewery said:

A good way to remove the magnets off their plates is to grab either end of that plate (NOT THE MAGNET!) with some vise grips or lock one end into a vise and twist the plate. The magnet pops right off the plate and you can use a paint scraper to pry it away. I broke a few of them using the hammer tap method. An acetone bath works to dissolve the glue as well.

Click to expand...

QFT, bending the bracket is the best way I've found for removing those little suckers. Also, DON'T FORGET THOSE SAFETY GLASSES! Little flying ceramic shards = bad for the eyes!

What strength magnets do I need? I do not have an old hard drive, so I will need to buy, but they describe as lbs of megnetism.

Kevin Dean said:

I took apart six hard drives. I have this huge stack of metal squiggly things with magnets adhered to them, but not a single one comes of the big metal piece and it's too big to use on the stirplate.

I went to a local hobby store and they had them so I got a handful.

Click to expand...

grab each end of the metal piece with a pair of needle-nose pliers. Twist the pliers in opposite directions. The magnet will come off from one end and come right off.....

I'd use the hard drive too, but I have purchased magnets from these guys before... http://www.kjmagnetics.com/. You end up paying more for shipping than for one or two magnets but, there are lots of other projects that call for super strong magnets.

This is where I get my rare earth magnets:

http://www.rare-earth-magnets.com/

Good selection, but the pricing with shipping is a little high. I get around that somewhat by placing a large order. Obviously, this is only practical if you can use enough of them to make it worthwhile, but you might do a group buy with some fellow brewers to get the delivered unit price down. I've tried using salvaged hard drive magnets, but decided they weren't worth the effort of removing and they are also difficult to align and balance.

amazon.com

I ordered min from kjmagnetics, but i've seen them at home depot recently also.

Your local Northern Tool has them too.

M_C