Thread Starter


Joined Jul 3, 2010
I have a project using Hall Effect sensors, I have been unable to find magnets suitable for the design. I would like the diameter to be .25", thickness <.25" and the magnetic density in the neighborhood of 300 - 1000 gauss. Digikwey has the size in 10800 gauss, not acceptable. any help is greatly appreciated.


Joined Sep 2, 2011
No info on the gauss strength, but Harbor Freight has 10 piece Rare-Earth Magnets 5/16 x 1/8", Item #67488

Also, the magnets found in audio/mp3 earbuds sure seem strong to me...and tiny to boot.

aka David M


Joined Sep 9, 2010
Menards often gives away (after rebate) magnetic tool-holder armbands, and these contain a number of powerful disk magnets.


Joined Sep 8, 2011
126 I have bought some of these a couple of times, supposedly made of neodymium. They are quite strong but since they are thinner I suppose they should be milder that the ones at digikey; I haven`t made measurements though. Still at that price it's great value.

Also you've got to take into account that the measured magnetic flux density is affected by angle, distance and temperature so if you want to use a hall effect sensor to determine the distance of an object, just put it further apart and it'll do the trick
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Thread Starter


Joined Jul 3, 2010
I checked out the site and the magnet offer. Since they are neodymium I suspect they are very strong. A footnote concerning packaging has me ordering 100 with no shipping charge, the price cannot be beat, thanks again. I need south poles for shaft speed, north poles can be used interposed to regen the battery.