Thread: rare earth magnets

I've got some with a cover and hooks that are the size of a 50c piece. They are good for 80 kg. I can hang whatever I want from the beams. and at 85kg I can pull them down as well.
The little 5mm long and 2mm round are good for small boxes, I put one in the top and one in the bottom and it keeps then down nicely.
You do not want to let them snap together to hard and they do shatter easily.
I also have 15mm round and 10mm thick, Those you can't pull apart. Only way to get them off each other is to slide them. Got a few blood blisters from those as well.

In the old cars you could hide a spare key underneath without any worry of them falling off.

It would be interesting to compare the different qualities from the various sources. I purchased some from Dealextreme a few years ago (as I was ordering some other stuff anyway and they were cheap) and whilst they are much stronger than regular magnets the ones I have don't seem to exhibit the amazing strength powers experienced by others. Not sure if they do vary in quality or it is simply a matter of the smaller sized ones I purchased.

Originally Posted by Sir Stinkalot

It would be interesting to compare the different qualities from the various sources. I purchased some from Dealextreme a few years ago (as I was ordering some other stuff anyway and they were cheap) and whilst they are much stronger than regular magnets the ones I have don't seem to exhibit the amazing strength powers experienced by others. Not sure if they do vary in quality or it is simply a matter of the smaller sized ones I purchased.

Hi Sir,

I think the strength of the magnet is dependent on a couple of factors. The N rating (if I can call it that) and the physical size of the magnet. Im not totally up with it but I think the N value correlates to the magetic flux? So obviously an N50 will be stronger than an N48 of the same size. I wouldn't think quality would come into it. It's either an N50 or it's not.

I get the feeling Stuart will have something to say on this. He's usually pretty clued up!

Cheers,

Simon

Thanks for the Enlightenment on RE Magnets.

Sound pretty handy. I'm pretty cheap, the last lot of magnets I got where from some speakers somebody dumped in the local park.

Ben

I've bought magnets from here
Magnets, Rare Earth, Neodymium, Flexible Magnets, Industrial Magnets . Australia
They have a good range and prices seem ok.

Originally Posted by YarrD

and I pop one into each plastic oil bottle near the lathe (way oil, spindle bearing oil, cutting oil) and sit the bottle in the swarf tray - cannot knock it over then

So does the bottom of the bottle look like a porcupine after a while - surely all the metal swarf will stick to it?

I personally don't particularly like magnets around machines and I try always to keep the mag base away from measuring tools.
If not careful one can end up with the tips of inside calipers, outside calipers ends of micrometers etc magnetized. They are then a real pain, luckily, by a recent purchase I now own an electric degaussing wand and can rectify the problem easily.

Just for interest on another note, anyone with children should be very vigilant when there are swallow-able size magnets around and in toys. If a small magnet ends up in one part of the intestine and another one ends in another part the magnets can clamp the intestine walls together, the magnets will then stay there and if this situation is not caught early can be a major problem.
One example, RSNA press release: Swallowing Multiple Magnets Poses Danger to Children
If interested, just do a Google on "small magnets in intestine".

Cheers.

Ouch!!!!
Thanks Log, i'll keep that in mind. We have corsage magnets for work, they are about 10mm x 5 x 3. I can put one in the palm of my hand and one will stick to the back of my hand.....

Can i ask where you got your degausser from? most of my screwdrivers are a magnetic, it a real pain!

Originally Posted by Ueee

Ouch!!!!
Thanks Log, i'll keep that in mind. We have corsage magnets for work, they are about 10mm x 5 x 3. I can put one in the palm of my hand and one will stick to the back of my hand.....

Can i ask where you got your degausser from? most of my screwdrivers are a magnetic, it a real pain!

Ouch all right, I first read about the dangers of small magnets when swallowed on BBC - Homepage some time back, apparently it's a growing problem.

I got the degausser wand on Ebay, buy it now for $25 plus some postage. I'll take a pic tomorrow and post it up.
I had been doing some research with the thought of making a small one when low and behold a random search on Ebay found one in Aus. I don't know what the degaussing wands for the tube type TV screens looked like but perhaps it's one of those, it's even Aussie made.


Cheers.

Extra info, The degausser wand I have is about 300mm long and 40mm diameter and the magnetic field, is at the end.

Cheers.

Originally Posted by Log;1507531
Just for interest on another note, anyone with children should be very vigilant when there are swallow-able size magnets around and in toys. If a small magnet ends up in one part of the intestine and another one ends in another part the magnets can clamp the intestine walls together, the magnets will then stay there and if this situation is not caught early can be a major problem.
One example, [URL="http://www2.rsna.org/timssnet/media/pressreleases/pr_target.cfm?ID=203"

RSNA press release: Swallowing Multiple Magnets Poses Danger to Children[/URL]
If interested, just do a Google on "small magnets in intestine".

Cheers.

iron deficiency would be a major problem.

Hmmm, If these magnets are as plentiful as they appear to be, why are they called "Rare" earth magnets?

( I know it its to so with what they are made of.lol)

bollie7

I thinks there are a group of elements in the periodic table that are classified as rare earth elements. Neodynium (don't even know if I have spelt it correct!) is one of those elements.

Silly name. Not even made of earth anyway, even if it is rare!

Simon

Rare earth elements (REE) are indeed relatively rare but even in a rare earth magnet the REE is a minor component.

e.g. Neodymium(Nd) magnets are by atom ration 14 atoms of iron, two of Nd and one of boron.

Australia is a major supplier of REE raw materials but increasing amounts of REE technology and production has been controlled by the Chinese. An example of this is that China produces more PhDs in REE R&D than the rest of the world put together. REE are essential components of hard drives and high performance small electric motors such as cordless tools.