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Where can I find four 50 pound lift or higher magnets that's round and flat?

They need to be flat and not too thick and I would prefer in a circle shape but square will also do. They have to be at least 50 pounds of lift. Price doesn't matter but I would prefer each one is at most $20.


Keep in mind that the shape of the magnet, the distance and angle between the north and south poles, is very important to how it will work.

  • If your magnet is long along its magnetized axis, its field will have more reach and penetrating ability, but will not have as much strength on thin surfaces.
  • If your magnet is fairly flat or ring-shaped, it will have intermediate strength and penetrating ability
  • If your magnet is in a well-designed cup or consists of poles arranged in alternating stripes or a checkerboard pattern, the magnet will stick very powerfully to even thin surfaces, but its strength will rapidly drop when pulled away from the surface.
Deal extreme's prices do look okay compared to some places, but I would suggest these two. They have the advantage of customer support people who don't speak Chinese. :)

Price guarantee:
http://www.magnet4less.com/

Good selection:
http://www.kjmagnetics.com/

I'd also suggest checking the prices of your magnet by volume. For example, the DealExtreme 100-pack of 10mm diameter by 1mm thick costs $7.34, or $15 per cubic inch- not such a great deal.

7.34USD / 100 / (pi * (5mm)^2 * 1mm) in usd per cubic inch
= $15 per cubic inch

Then according to you, I need a magnet long along its magnetized axis with a more reaching field and penetrating ability. Thanks for the sites!
fireblast_1212 (author)  fireblast_12125 years ago
Hey, NobodyInParticular, I just checked out the sites you gave me and found a 1 1/4 x 1/8 round magnet with a pull force of 81 pounds! You are the best!
frollard5 years ago
unbeatable prices for these: and free shipping :D

http://www.dealextreme.com/products.dx/category.1105~r.84995416

18mmx2mm 10 pack for 4 dollars shipping included
http://www.dealextreme.com/details.dx/sku.10304~r.84995416

disclosure: I get a referral affiliate bonus (although tiny) for you buying anything there, but seriously, the prices are amazing. They take paypal and credit card.
fireblast_1212 (author)  frollard5 years ago
None of those are good enough but thanks for the support!
No worries - I'm gonna pick some of these up on my next order - and see their holding strength each/in an array :D I'm thinking complex grid of these as an alternator in a permenant magnet wind turbine.
http://www.rare-earth-magnets.com/ has bigger stuff if those arent strong enough. (I'd rather use 4 dollars worth of small ones than one expensive big one.
fireblast_1212 (author)  frollard5 years ago
Thanks, I found a pack of 4 that can lift 4 pounds each for $10. I can use several together instead of a big one.
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