odd question re: magnet resource

[rob_s]

I'm looking for a resource on magnets. I have a need for a magnet that can attach itself to steel through approximately 1/4" thick, but not so strong that it can't be removed.

Ideally I'm looking for a resource for such things as I may have need of magnets that can hold things through different thicknesses of material (say, a magnet that can hold ~40 oz through ~1/2" of wood...)

[awp_101]

Check with a local appliance repair place to see if you can get the magnets out of used microwave magnetrons.

[mmc45414]

I am always amazed how much stuff is out on Amazon:
https://www.amazon.com/s?k=magnets&ref=nb_sb_noss_1

Maybe a little better performance information on McMaster:
https://www.mcmaster.com/standard-magnets

[rob_s]

I am always amazed how much stuff is out on Amazon:
https://www.amazon.com/s?k=magnets&ref=nb_sb_noss_1

Maybe a little better performance information on McMaster:
https://www.mcmaster.com/standard-magnets

I've been reading through Amazon, and in a way it's an overwhelming amount of non-information. So many vendors selling so many diffrent versions with only a few having any sort of information regarding the strength of the magnet, and then me not knowing how to interpret said strength.

I found another site totally devoted to magnets, with every sort of size and strength imaginable, so I emailed htem. Short of that my cart there is currently full of every ~1/4" diameter magnet from 2 to 10 lbs of force in 2 lbs increments.

[mmc45414]

I've been reading through Amazon, and in a way it's an overwhelming amount of non-information.

It seems like with Amazon you would probably just have to try a couple, they seemed cheap.

And if you are not accustomed to buying from McMaster, know they are pretty solid on shipping same day.

[JTQ]

I'm looking for a resource on magnets.

Florida State University's National High Magnetic Field Laboratory https://physics.fsu.edu/research/nat...eld-laboratory

[Guerrero]

If you have an old hard drive, the rare-earth magnets in those are pretty bitchin'.

[txdpd]

IIRC from a book I found on speakers, wood has essentially no magnetic shielding properties.

The “strength” Of magnets is usually measured as a force that’s pulling perpendicular to the plane of the mating surfaces. If you’re hanging something on the ceiling you could use a “40lb” magnet to hold 40 pounds. If you’re hanging on the wall you would need a coefficient of friction.

https://www.kjmagnetics.com/calculator.asp

[JTMcC]

We use strong magnets in our work and have done business with K&J Magnetics for over 15 years.
They are good at answering application questions. When they say "be careful" they really mean it, but if you choose the proper power in the proper size, with the proper attachment method, it's really nice.

[sparkyv]

If you have an old hard drive, the rare-earth magnets in those are pretty bitchin'.

Ditto on the hard drives.