De-magnetizing a blade.

[Ken C.]

What is the best way to de-magnetize a blade if I don't have access to a de-magnetizer? The tip on a knife I own is slightly magnetic and i would like to get rid of that annoyance.

 

[rebeltf]

Try this

Tip: "Demagnetize ´em"

Screwdrivers, pliers or other small tools magnetized?
Easy to fix!
Get a soldering gun, with the dual tips that connect, and pass the tools through the two tips, while the gun is on.
This will demagnetize your tools!

Let me know if it works I doubt the heat is enough to damage the blade, anyone else ?

 

[apw]

Try taking a permanent magnet and stroking the blade in circles, alternating directions frequently. If it is only magnetized a little bit, this should realign the domains enough to demagnitize it.

 

[howiesatwork]

As rebeltf mentioned, a Weller soldering gun.
Or a demagnitizer from Radio Shack (64-2974 $3.99)...

 

[erdvark]

Try taking a permanent magnet and stroking the blade in circles, alternating directions frequently. If it is only magnetized a little bit, this should realign the domains enough to demagnitize it.

That's liable to actually increase the magnetization. The soldering gun trick might work, the key is to put the blade into the gap and pull it out slowly and move it far away before turning off the gun. This technique is what we used to use for erasing magnetic tape back in the day. The best thing is to find someone with a bulk eraser or a head demagnetizer, but they are rare because no one uses magnetic tape anymore. One other thing to try is to get an aquarium pump, the kind that buzzes and take it apart to get the coil. Use that with the technique described above.

 

[howiesatwork]

On the soldering gun, turn the gun on, then draw it across the back of the gun.
A degaussing coil in action.

 

[Sword and Shield]

I degaussed one by simply putting it on top of my TV and hitting the degauss button- it's a horseshoe magnet with an X through it.

 

[erdvark]

I degaussed one by simply putting it on top of my TV and hitting the degauss button- it's a horseshoe magnet with an X through it.

That's clever, you can also see how much it's magnetized by holding the blade near the screen, the colors will go wonky.

 

[WarRaven]

If you smack it while it lays north south or south to north, you will magnetize it. Or turn it east-west or west-east, an hit it hard again it will lose the magnetivity.

Try it with an old butter knife or a screwdriver, works.
I realize you may not want to hit your knife,it although is another way.

WR

 

[EdgePal]

Screwdrivers is sometimes fine to have magnetized. That is easy to do, just take a magnet, hold it to the screwdriver (on the steel) and drag it along the screwdriver to the end, lift it up and do it again, always in just one direction. Do this 2-3 times and you have a magnetic screwdriver.

To un-magnetized the screwdriver is easier, hold it in the handle with two fingers and hit the anvil, or the vice, with the steel part, it do not need to be hard, just do it fast. If you do this right, it is not magnetic any more after that hit. It works for me, have used it for decades.

You can use this in any tool, also knifes, but, the fast “hit” on the vice can make marks on the blade.

Sometimes it works that you hit the steel part with a hammer, try to hit the middle part of the steel and do it fast, not hard. I do not know if it is the vibrations who makes the magnetism to go away or if it is just the fast hit – but it works. To hit the vice or the anvil, is a easyer and more secure way to do it.

Thomas

 

[Phil Brown]

To demagnetize, you use a magnet (permanent or electro) like an orbital sander. When you sand in one direction, it leaves an impression of the sanding disk. To compensate, you have to sand in different directions, covering up the sanding marks until they can no longer be distinguished. A random orbital sander does this for you. When you move the magnet along the blade, you're leaving magnetic "marks" in that direction. So you have you to go back over it in lots of different directions to jumble up the domains and return the metal to its natural non-magnetic state.

 

[apw]

That's liable to actually increase the magnetization.

Only if you stroke it in one direction only. I've used the method on my multitool that was magnetized accidentally. It may take some time, but it works.