Originally Posted by
jacobite
They are the very fellows, also called earth magnets, I believe?
I've used a few of these on caches I've customized, and these little guys can really stick!
I bought mine on ebay, and as HH says, the keyword is Neodymium.
Generally called 'rare earth' magnets and are made of Neodymium Iron Boron but they need some sort of surface treatment like nickle plating. If the plating comes off, then they tend to disintegrate. If you can find them, magnets made of Samarium Cobalt are very nearly as strong and don't require any surface treatment; they will work 'raw'
If you have an old computer hard drive that's U/S then there are one, sometimes two, very strong magnets in them that are usually bonded onto a steel backplate with holes in. That can make attaching them to a cache box a bit easier. I went into a local computer repair place and asked if they had any scrap HDDs, told them exactly what I wanted them for and they gave me half a dozen.
John
Age and treachery will always triumph over youth and ability.