Magnets strong enough for caching

[lemmykc]

I owe a huge thank you to Geoff (gmj3191) for dropping off an already made magnetic cache container at my house today, a very kind thing to do. I am still interested to hear all about Magnets though as I will probably need to know one day.

Again, thanks Geoff

[Rainbow Spirit]

I'm a big fan of rare earth magnets, I got 40 disc type ones (25mm x 2mm) from Aussie Magnets for $40.

I thinks magnets work better in the long term if you put them inside the container, if you put them on the outside the glue/tape will eventually fail with constant removal of the container. If they do fall off in the container, they will still be there, and they will still hold the container in place. Yes there will be less magnetic power through the container's wall thickness, so you will need to remove any lips, etc on the outside of sistema type containers, so as to reduce the distance from the magnet/s to the steel item you are attaching to. Also the thicker the steel, the stronger the magnetic attraction.

[Toriaz]

...
I thinks magnets work better in the long term if you put them inside the container, if you put them on the outside the glue/tape will eventually fail with constant removal of the container....

I have only one container with magnets, I used ones from an old hard drive. When I first made the container, I asked my husband to glue the magnets on for me, and assumed he would put them on the inside. He put them on the outside, then tested it for me by attaching the container to our bbq. Called me to report that he would need to find some stronger glue, because when he'd tried to remove the container from the bbq hood, the container had come away leaving the magnets in place .

He hadn't even considered the idea of gluing the magnets inside and I thought it was so obvious I hadn't mentioned it to him. After he managed to pry the magnets off the bbq, he glued them on the inside for me, it works perfectly now .

[noikmeister]

Remember anything between the magnet and the steel you're attaching it to will decrease the pull of your magnet.

Magnetic force is subject to an inverse square law. So if you double the distance between the magnets you get 1/4 the force.

[Alansee]

A couple of thoughts from my experiences with these. Well, three thoughts actually.

1. Almost always go for the stronger magnet. It is hard for the magnet to hold too hard, and very easy for it to not hold hard enough. As a consequence I always use rare earths. And yes, those HDD ones are excellent.

2. By necessity I use eclipse tins from time to time, inside which I use a 10 x 1 mm rare earth magnet, which works very well. I once tried a 3 x 1mm magnet, but it flipped onto the bottom of the container and compromised the hide. A 10 x 1 won't do that.

3. Don't underestimate the reducing effect of putting something between the magnet and the metal. Even just the plastic of a container is enough to bake a big difference.

[calumphing_four]

I thinks magnets work better in the long term if you put them inside the container, if you put them on the outside the glue/tape will eventually fail with constant removal of the container. If they do fall off in the container, they will still be there, and they will still hold the container in place. Yes there will be less magnetic power through the container's wall thickness, so you will need to remove any lips, etc on the outside of sistema type containers, so as to reduce the distance from the magnet/s to the steel item you are attaching to. Also the thicker the steel, the stronger the magnetic attraction.

Have to say I totally disagree with this - at least for eclipse tins, and other metal tins.

Best method with eclipse containers is to put the magnet on the outside, and don't stick or glue or tape the magnet. When you have hidden your cache, you'll find:
1. that finders can more easily extract the log book, as there is no magnet making the space narrower, nor attracting the staple
2. the attraction is stronger
3. when a finder grabs the container, the magnet stays inplace, so they have to return it to where you had planned
4. if it is muggled you only need to replace the eclipse tin - I've yet to lose a magnet this way

For Sistemas you can tape some ferrous metal to the outside to protect the magnet from muggling and to make the attraction stronger.
However, if you do decide to put the magnet inside the sistema, ensure you have a backing on the magnet to use the principles of magnetic lines of force and get a stronger attraction between the cache and the object you are hiding the cache on.

Cheers

[darth trader]

I just received a 1 inch diameter spherical neodium magnet in the mail from americia.

It can hold a Women's weekly on the fridge.


- why DO they call it a weekly when it is published monthly?

[gmj3191]

I just received a 1 inch diameter spherical neodium magnet in the mail from americia.

It can hold a Women's weekly on the fridge.

HDD magnets hold them strongly on the fridge.

[gmj3191]

A lucky cacher in Brisbane who is prepared to pick up a box of 13 hard drives from Chelmer may
be interested in this item on eBay
http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 500wt_1156

Thanks for the heads up on fleabay item; I'd been looking for some HDD magnets. Made a modest bid but if someone (cacher?) else is more interested, ...

These 13 drives, potentially 26 magnets, went for $5.50. Hope you get them GreenFish.

[PesceVerde]

A lucky cacher in Brisbane who is prepared to pick up a box of 13 hard drives from Chelmer may
be interested in this item on eBay
http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 500wt_1156

Thanks for the heads up on fleabay item; I'd been looking for some HDD magnets. Made a modest bid but if someone (cacher?) else is more interested, ...

These 13 drives, potentially 26 magnets, went for $5.50. Hope you get them GreenFish.

Thank you. I think it was my lucky bid.

[Damo.]

I just received a 1 inch diameter spherical neodium magnet in the mail from americia.

It can hold a Women's weekly on the fridge.


- why DO they call it a weekly when it is published monthly?

There is already a Women's Monthly and it's something completely different.....