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After reading this, I learned it is not advisable to solder a wire to neodymium magnets.

After more reading I found this post describing the use of conductive epoxy to bond electrical wires to neodymium magnets, a very messy process which takes several hours of waiting.

I want to ask this community if they have or suggest better methods to bond/connect a wire to a neodymium magnet to act as a conductive connection?

lucidgold
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  • Contrary to your links, samarium cobalt magnets can withstand soldering temperatures (although they will need to be plated with something solderable first; unlike neodymium magnets they are usually supplied unplated), and conductive epoxy should not be messy or take a long time to cure if you buy good quality epoxy, mix it properly, and cure at the proper temperature. Anything that claims to cure at room temperature is probably not worth the money. – Oleksandr R. Jan 16 '16 at 20:03

4 Answers4

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Warning: untested answer.

I understand that you are making a 'conductive connection' and that the magnet is to be one 'pin' / pole of the connector and that it should maintain conduction with the mating part by surface-to-surface contact with contact force being maintained by magnetism. My answer proposes that you use the same method at the rear of the magnet.

Solder the wire to a ferrous metal disc. A steel washer might suffice but you may have to remove some coating. If the disc is not perfectly flat you could file / sand it to improve contact. Attach the disc to your magnet.

Once you're happy with that you can epoxy coat the rear to prevent rust or sliding and, perhaps, ensure that the connection breaks at the intended point, i.e., the contact face separates rather than the wire and washer pull off.

Have you a sketch of the finished article?

Transistor
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  • Interesting, how do you propose I attach the disk to a magnet making an electrically-conductive bond? – lucidgold Jan 16 '16 at 17:47
  • Thank you. Answer expanded to explain. If a magnetic bond is good enough for the contact face it should be good enough for the wiring face. – Transistor Jan 16 '16 at 18:05
  • Ahh, makes sense! – lucidgold Jan 16 '16 at 18:07
  • +1. If the surface of the magnet is good enough to make an electrical contact to whatever you attach it to, then I see no reason why it wouldn't also work on the other side where the washer is attached. – Tom Carpenter Jan 17 '16 at 03:23
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A spring clip would work. Depending in what exactly you want to do with it, you might be able to use a gold-plated spring loaded pin.

enter image description here

Typically one would design the holder so that the pin is depressed to about 50% of the stroke.

Spehro Pefhany
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If you get the right size those end caps from 5AG or 3AG fuses could be soldered to and then pushed onto the magnet, (or you could start with end caps that have welded leads)

Jasen Слава Україні
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In the past, I've soldered a metal disc to wires, and then shrink tubed the magnet to the that, then cut off a circle out of the shrink tube to expose enough of the magnet face to make a conductive connection to the battery.

Another method I've used is to get a cr2032 open face battery holder (without a clip on top), and get a neo mag that's roughly the same size, and clip it in there, then solder a wire to one of the leads; either one, doesn't matter.

The battery holders look like this: https://m.media-amazon.com/images/I/51nBtKBVZ4L.jpg

The magnets were 20mm x 3mm, and fit perfectly.

then you just wire them to your circuit and snap them to your batteries.

Voltage Spike
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Rich.Weber
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