# Removing filings from magnet **URL:** \ **Category:** Factual Questions\ **Created:** [May 21, 2017, 4:00pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146 "2017-05-21T16:00:41Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [May 21, 2017, 4:00pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/1 "2017-05-21T16:00:41Z")
Take a small permanent magnet and pour iron filings over and around it, the way children sometimes play. The question is, is there an efficient way to remove the particles, leaving the magnet clean again? ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [May 21, 2017, 4:11pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/2 "2017-05-21T16:11:34Z")
Sticky tape. Or Blue tack. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [May 21, 2017, 5:05pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/3 "2017-05-21T17:05:32Z")
But then the iron filings are stuck to the tape. I’d start by just brushing the filings off the magnet. Or get a more powerful electromagnet, use it to draw the filings away from the permanent magnet and then turn off the electromagnet. The filings should fall right off. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [May 21, 2017, 5:10pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/4 "2017-05-21T17:10:33Z")
> [@Dewey\_Finn](#): > > Or get a more powerful electromagnet, use it to draw the filings away from the permanent magnet and then turn off the electromagnet. The filings should fall right off. Probably a bad idea. You could end up demagnetizing your original magnet if you’re not really careful. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [May 21, 2017, 5:14pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/5 "2017-05-21T17:14:20Z")
Are the filings already stuck on the magnet or is this going to happen in the future. IOW, can you just cover the magnet with something that can be peeled off or is it already done. Also, depending on exactly what you’re doing, they do make non-electromagnetic magnets with an ‘on/off’ switch. I assume the switch just moves a magnet away from the surface, but it may work in your application and be easier than pulling tape off a magnet or putting the magnet in a bag each time. Going forward, prevention is probably best, but if it’s a one and done, you’re probably going to have to brush them off one way or another. Maybe with a dry cloth or even putting on a glove and wiping them off by hand. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [May 21, 2017, 5:22pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/6 "2017-05-21T17:22:44Z")
> [@Little\_Nemo](#): > > > [@Dewey\_Finn](#): > > > > But then the iron filings are stuck to the tape. I’d start by just brushing the filings off the magnet. Or get a more powerful electromagnet, use it to draw the filings away from the permanent magnet and then turn off the electromagnet. The filings should fall right off. > > Probably a bad idea. You could end up demagnetizing your original magnet if you’re not really careful. Who cares? The parameters of the problem didn’t require us to preserve the magnet. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [May 21, 2017, 5:32pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/7 "2017-05-21T17:32:16Z")
FWIW careful brushing+wiping gets most of them off, and then a bit of sticky tape takes care of the remaining dust. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 21, 2017, 5:43pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/8 "2017-05-21T17:43:55Z")
Soak the magnet in water. The iron filings will turn into non-magnetic hematite and fall off. ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [May 21, 2017, 6:53pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/9 "2017-05-21T18:53:22Z")
Maybe jam some Silly Putty or similar substance over the filings? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 21, 2017, 7:17pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/10 "2017-05-21T19:17:24Z")
I’d pull off as much as I could by hand, and then get a second magnet. Put a layer of something thin (paper or whatever) over the second magnet, and put it up against the original magnet. When you pull them back apart, each should have about half of the filings. Remove the paper from the second magnet, and drop the filings into whatever container you’re storing them in, then put the paper back on and repeat. Each cycle, you’ll remove half of the filings, until the amount left is small enough to not worry about. ---
**Author:** ![yabob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yabob/32/2821_2.png) [@yabob](https://boards.straightdope.com/u/yabob)\ **Post date:** [May 21, 2017, 8:08pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/11 "2017-05-21T20:08:47Z")
> [@DPRK](#): > > FWIW careful brushing+wiping gets most of them off, and then a bit of sticky tape takes care of the remaining dust. Yeah, but the variant I’d use is to scrape them off with a paint scraper or similar utensil while holding the magnet over a sheet of paper. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [May 21, 2017, 8:57pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/12 "2017-05-21T20:57:30Z")
Joey P. had it right – prevent it from happening. Usually, this is done to show children/students how magnetic force works. It’s easy to do that by putting the magnet underneath a sheet of white paper or a clear plastic page protector – then the filings move around on the sheet, but don’t stick to the magnet. And it’s usually easier to see the movement on a sheet like that. ---
**Author:** ![Weisshund](https://avatars.discourse-cdn.com/v4/letter/w/ba8739/32.png) [@Weisshund](https://boards.straightdope.com/u/Weisshund)\ **Post date:** [May 21, 2017, 9:03pm UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/13 "2017-05-21T21:03:00Z")
I just wipe the magnets off with a shop rag, if i need to, hit it with some compressed air. Works for what i need ---
**Author:** ![48Willys](https://avatars.discourse-cdn.com/v4/letter/4/db5fbb/32.png) [@48Willys](https://boards.straightdope.com/u/48Willys)\ **Post date:** [May 23, 2017, 5:31am UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/14 "2017-05-23T05:31:54Z")
> [@Weisshund](#): > > I just wipe the magnets off with a shop rag, if i need to, hit it with some compressed air. > Works for what i need This! Just remember to wear safety glasses. You do not want iron filings in your peepers. Trust me on this. I do wonder though, how hot would one have to get the magnet for it to loose it’s effectiveness? Big crane mounted electromagnets will get hot & quit picking up steel parts. What if you boiled a permanent magnet in oil? Could you then just remove the magnet from the kettle while it was hot? Oil would be used so that the iron filing will not rust. The next rainy day when i have my grand kids, I think that we may try this. ---
**Author:** ![anomalous1](https://avatars.discourse-cdn.com/v4/letter/a/e56c9b/32.png) [@anomalous1](https://boards.straightdope.com/u/anomalous1)\ **Post date:** [May 23, 2017, 5:33am UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/15 "2017-05-23T05:33:03Z")
If the magnet is of large enough size, use a plastic putty knife, if it isn’t too powerful, try a metal putty knife, or razor/scraper (the dollar store ones used to take off old City Stickers). This is of course if you are trying to preserve the filings. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [May 23, 2017, 5:37am UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/16 "2017-05-23T05:37:36Z")
> [@48Willys](#): > > I do wonder though, how hot would one have to get the magnet for it to loose it’s effectiveness Hot. [Seriously hot.](https://en.wikipedia.org/wiki/Curie_temperature) 1000K plus. Propane torch will do it. Medium red is where you need to get it. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [May 23, 2017, 6:08am UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/17 "2017-05-23T06:08:34Z")
Right, but why cook a perfectly good magnet? 😛 ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [May 23, 2017, 8:17am UTC](https://boards.straightdope.com/t/removing-filings-from-magnet/787146/18 "2017-05-23T08:17:13Z")
> [@Dewey\_Finn](#): > > But then the iron filings are stuck to the tape. I’d start by just brushing the filings off the magnet. Or get a more powerful electromagnet, use it to draw the filings away from the permanent magnet and then turn off the electromagnet. The filings should fall right off. The OP did not say that he wanted to preserve the iron filings.