# Split large magnet into smaller pieces



## fixit7 (Jul 15, 2020)

I salvaged this 10 lb magnet from a 1000 watt speaker.

I trying to make smaller magnets from it.

Wikihow says to either chip it with a hammer or saw it with a hacksaw.

What do you think?


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## fixit7 (Jul 15, 2020)

No one ?


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## slownsteady (Jul 16, 2020)

I suppose it depends on what you're going to do with it. If you break it into chunks it will have rough surfaces, which you may find less useful or unattractive.

I think you should leave it whole and put it on the fridge to hold up a calandar


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## fixit7 (Jul 16, 2020)

slownsteady said:


> I suppose it depends on what you're going to do with it. If you break it into chunks it will have rough surfaces, which you may find less useful or unattractive.
> 
> I think you should leave it whole and put it on the fridge to hold up a calandar



It does not bother me if the chunks are not attractive.

Putting a 10 lb. magnet on my fridge is not attractive.


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## JoeD (Jul 16, 2020)

If you don't care about size and shape of the pieces smash it with a hammer. Otherwise use a hack saw or grinder to cut it apart.


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## Jeff Handy (Jul 17, 2020)

Tie a sturdy rope to it, use it for magnet fishing for stuff in a lake.


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## fixit7 (Jul 17, 2020)




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## Jeff Handy (Jul 18, 2020)

Cool!

That is an easy way to get “hammered”. 

You should put that in your luggage when going through airport security. 
That will make for an interesting day.


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## fixit7 (Jul 18, 2020)




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## Jeff Handy (Jul 18, 2020)

Years ago, I was visiting my youngest sister, and discovered that her five year old son was obsessed with taking things apart to study them, just like I was at his age. 

He had an old hard drive and was trying to get into it. 
I showed him how to bash it apart, and that the coolest things inside were the EXTREMELY strong magnets. 

He took them over to a nearby lally column to stick them on, and they instantly and painfully snapped down onto his little fingers. 

I rescued his pinched fingertips, and I taught him a life lesson. 
“Not everything that adults tell you can be trusted, or ignored”.


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## Johnboy555 (Jul 18, 2020)

I think I have lost all respect for you Fixit!
Don't use it for tools, later you will find them covered with metal filings. Stick a handle on it to pick up nails/screws  off the floor.


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## fixit7 (Jul 18, 2020)

That was my intention as well.

Don't worry, be happy.  (and flexible)


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## zannej (Jul 18, 2020)

I have no suggestions. I've never tried to break up a large magnet. Sorry.


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## havasu (Jul 18, 2020)

I will add that a rare earth magnet is 1/10th the size and picks up twice the weight.


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## tomtheelder2020 (Jul 19, 2020)

Bashing it apart will be an interesting experiment.  Cut a bar magnet in half and you have two identical smaller bar magnets, but what will the polarity be for chunks from a ring magnet? Will a big piece be a curved bar magnet with polarity at the ends, or front to back? If you slice a narrow wedge, how would the polarity work?  I think this is a question for someone who knows a lot more physics than me.


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## Jeff Handy (Jul 19, 2020)

Smashing it could create some wicked flying metal pieces.


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## zannej (Jul 19, 2020)

I would think that putting on safety glasses & cutting it w/ a metal cutting attachment or scoring it & trying to snap it like glass against a flat surface might work better-- but I don't know what the thickness/size/shape of this magnet is. Smashing it seems like it's begging for debris flying everywhere.


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## Jeff Handy (Jul 19, 2020)

Razor sharp flying shrapnel.


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## fixit7 (Jul 19, 2020)

You can _break_ a magnet into smaller pieces by _scribing_ the break lines onto the magnet surface with a single point diamond scribe and then flipping the magnet over and striking the backside of the magnet surface with a hammer and chisel, where the chisel edge is aligned with the direction of the scribe line on the opposite side.


But the best way to accurately separate a magnet into smaller pieces is with a diamond-wheel grinder.



			https://www.amazon.com/Masonry-Diamond-Performance-General-Concrete/dp/B075DK2ZST/ref=sr_1_1_sspa?dchild=1&keywords=230mm+diamond+angle-grinder+disk&qid=1595179915&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFYNEFTRFhYWDY0QkEmZW5jcnlwdGVkSWQ9QTA3OTI4NzYyODZDRzJOUEZBUjM2JmVuY3J5cHRlZEFkSWQ9QTEwNDM2NzIxMkpFUDVIVEpDVldTJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==


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## zannej (Jul 19, 2020)

Ok, NOW the image showed up for me. LOL. Internet was being stupid & wouldn't show it earlier. That's a large magnet. Sounds like cutting w/ diamond wheel grinder is the way to go. Remember to wear safety glasses though.

What sizes do you want the smaller ones to be?


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## fixit7 (Jul 19, 2020)

About 1 inch. 

Depends on how fast the diamond wheel gets dull.


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## bud16415 (Jul 20, 2020)

I used to do a lot of tooling work for a company called Eriez Magnetics. They gave me a part to fixture to machine that was aluminum but was a super strong magnet. I asked them what it was made from. Here they embedded a magnet in a molded aluminum casting and then heated the casting and then rapidly cooled it to cause the magnet inside to shatter into thousands of pieces. Then would magnetize it and the sum of all these little magnets would be stronger than one big one and all the poles would be held aligned within the casting.



All I know is when they would stick this part into my fixture and machine the aluminum it was a devil to get out as I made my fixture from steel.



Keep it in one big ring. I just changed out my sub woofer drivers in my home theater as one was blown. My amp is around 1000 watts and powers both at something like 500 RMS each. I thought about pulling the magnet out of the bad one but haven’t yet.

As a kid my buddies dad fixed B&W TVs and he and I were allowed to tear down the junk sets to get all the copper coils out for scrap. There were also a lot of magnets in them and I always had an 8 quart basket of magnets to play with. We used to build little DC motors kind of science fair like using the magnets. Some of them ran pretty good.


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## fixit7 (Jul 20, 2020)

bud16415 said:


> I used to do a lot of tooling work for a company called Eriez Magnetics. They gave me a part to fixture to machine that was aluminum but was a super strong magnet. I asked them what it was made from. Here they embedded a magnet in a molded aluminum casting and then heated the casting and then rapidly cooled it to cause the magnet inside to shatter into thousands of pieces. Then would magnetize it and the sum of all these little magnets would be stronger than one big one and all the poles would be held aligned within the casting.
> 
> 
> 
> ...


That magnet was a bear getting it separated from the steel ring. I had to use 3 levers at the same time.


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## slownsteady (Jul 21, 2020)

...leave it whole, get a mouse to jump thru the middle and see if ends up in another universe.......

(have you noticed that we often have fun here?)


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## ajaynejr (Jan 29, 2021)

Dropping a magnet on a hard surface, or hitting it, can weaken its magnetism.


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## Flyover (Jan 29, 2021)

You've got the magnet, which is great, but you don't yet have the other piece you need which is the enormous copper coil.


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## ajaynejr (Jan 29, 2021)

The copper coil is not needed to use the magnet as a magnet. The copper coil is used to make a loudspeaker out of the magnet (and other components).


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## Flyover (Jan 29, 2021)

I was thinking rail gun or dynamo, but sure.


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## Jeff Handy (Jan 29, 2021)

I vote rail gun!


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## Glenn_S (Mar 9, 2021)

Add a flux capacitor and get up to 88mph and...


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## Eddie_T (Mar 9, 2021)

I broke one while trying to remove it from an old speaker and due to the strong magnetic field the chips didn't scatter.


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