Magnetizer / Demagnetizer - does it really work?

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Haggai
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Magnetizer / Demagnetizer - does it really work?

I find myself more and more in need of a magnetizer and, more importantly, a demagnetizer... 

After giving up on the demagnetizing magick of the silly boxes (which magnetize quite well, actually), I think I need something more serious.

Can this demagnetizer really work?

Don
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As long as it actually has components inside it, it should be fine.

 

I'd always wondered about those first things for demagnetising.

 

An alternative is to heat the object above its Curie point - for steel that's about 770 Centigrade so not a real convenient alternative.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

Haggai
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I read somewhere that hitting the magnetized object real hard (e.g. a powerful knock with a hammer) can also demagnetize (or was it to magnetize?).

I tried, but it never worked.

okwchin
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I find my really high quality steel tools (screwdrivers) magnetise well naturally. They get knocked around..

 

Its all about creating random directions throughout the material, thereby resulting in no net direction of magnetism. I GUESS that the powered ones are AC powered coils, rotating the magnetic fields in opposite direction, hopefully not creating a particular direction??! thats my guess..

Fixed ones are only good at demagnetising the magnetic field of the opposite direction. So its technically difficult to de-magnetise.

 

The only things ive demagnetised are Neo magnets, by heating them above 80 deg C. :((((

"like everyone else - I’m looking for my next “last” flashlight" -  ohnonothimagain

fishinfool
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I've had one of those Magnetizer / Demagnetizer for years and it works great as a magnetizer but not so much as a demagnetizer.  Maybe the newer ones work better.

 

Don wrote:

"But as I said long ago, you are more likely to be killed by a dead fish dropped by a seagull in the Sahara Desert than by a lithium ion

Haggai
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fishinfool wrote:

I've had one of those Magnetizer / Demagnetizer for years and it works great as a magnetizer but not so much as a demagnetizer.  Maybe the newer ones work better.

Which one are you referring to - the passive with two holes or the active AC one?

fishinfool
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Haggai wrote:

fishinfool wrote:

I've had one of those Magnetizer / Demagnetizer for years and it works great as a magnetizer but not so much as a demagnetizer.  Maybe the newer ones work better.

Which one are you referring to - the passive with two holes or the active AC one?

It's this one from sears.

http://www.sears.com/shc/s/p_10153_12605_00945021000P

 Here's the same from Amazon.com

http://www.amazon.com/General-Tools-Pro-Magnetizer-Demagnetizer/dp/B0000WU1N4

 

Don wrote:

"But as I said long ago, you are more likely to be killed by a dead fish dropped by a seagull in the Sahara Desert than by a lithium ion

Haggai
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Oh, ok.

I ordered the active one from FocalPrice, when it arrives I'll write here if it works.

Haggai
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And it works!

Amazing!

Not only can it demagnetize screwdrivers pretty quickly (magnetized with one of the silly magnetizer/demagnetizer boxes) but it can also magnetize them slightly. 

To magentize - place the screwdriver on the "operation field" (Chinese for the device part the covers the magnet) and press the button for a few seconds. Leave the button and only then remove the screwdriver. 

To demagnetize - place the screwdriver on the "operation field" and press the button for a few seconds. While the button is pressed pull the screwdriver slowly away from the "operation field" and only when at least 10cm from the device leave the button.

Works great, I really love it Smile

http://www.focalprice.com/detail_HT431L.html and they sent me one with the correct plug (European).

 

And this is hilarious: I opened it up to see what's going on in there... simplicity FTW!! Big Smile

okwchin
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oh lol!!!!!!!

 

AC electromagnet! lololo!L!!!  I like it!

"like everyone else - I’m looking for my next “last” flashlight" -  ohnonothimagain