Introduction: 3D Magnetic Field Viewer

Picture of 3D Magnetic Field Viewer

My job takes me to various research labs to install powerful magnetic systems and to train techs how to use them. This time I needed a magnetic field viewer to show lines of force. This instructable will show how to construct such a device using steel wool fibers and mineral oil. I built this while I was staying at my hotel.

Step 1: Get Your Supplies

Picture of Get Your Supplies

I went to Walmart and got the following items and brought them back to my Hotel.

1. Fine steel wool.
2. Bottle of Mineral Oil in plastic bottle.

Step 2: Cut the Steel Wool

Picture of Cut the Steel Wool

Use the scissors to cut the steel wool into small short pieces. About a tablespoon of cut steel wool should be enough. Spread out sheets of newspaper on your work surface and try not to get clippings all over the place.

Step 3: Place in Bottle of Oil.

Picture of Place in Bottle of Oil.

Place the cut steel wool in the bottle of mineral oil. Clean the top of the bottle with a paper towel so you will get a good seal. Squeeze the sides of the bottle as you put on the cap to burp out the air. Shake to disperse the fibers.

Important note: Clean up any mess, and dispose excess fibers in your trash immediately. Place it in a plastic bag so it doesn't spread all over. The longer your mess sits around, the more likely you will spread it.

Step 4: Test the Viewer

Picture of Test the Viewer

Place a magnet against the bottle. The viewer will show the lines of force.


ANDY! (author)2012-01-15

Real cool idea. just wondering if you lit the wool and made...rust, would it still be magnetic?

AshcoV (author)ANDY!2018-01-16

Rust would not be magnetic as it is no longer a "metal"; just a collection of oxides.

AshcoV (author)2018-01-16

Very helpful, I needed a tester like this for my independent project at school.

maximzodal (author)2014-04-18

Just found this and it's a terrific project! Wish I had had this when I was teaching. Any problem with the particles becoming permanently magnetized?

botronics (author)maximzodal2014-04-22


kelseymh (author)2012-10-15

In fact, his statement shows that the Internet (in the form of a wide area network of networks) has been around for 43 years (2012-1969 = 43).

And I would ask you exactly the same question? Are you planning to participate in this now three year old discussion, for which the last contribution was made twenty months before yours?

CitizenScientist (author)2012-01-15

Great project, I am a physics teacher and this will make a great project for my students. Ideally I would like to make this in a container that has a hole in the center in which The students could slip a magnet and see the field on all sides around the magnet, instead of just one side. I will have to do some wandering about Walmart and see if I can see a bottle like this.

Thanks for the great project!

Beware the potential mess. Seals against flexible sheets are tricky. Try a Klein bottle or distillation condensers, maybe? A decent scientific glass shop could easily fabricate a tube through a flask'. Great 'ible. Great idea to extend the concept.

You could cut out holes for pvc pipe and then seal around the edges with silicone. That should easily accomodate a bar magnet.

Thats an interesting idea. I've seen some rubber stoppers at our local brew store that have a 3/8 hole in them. You could slip a small test tube through the hole. Another idea would be to find a test tube just the right size to fit a plastic bottle. Add a couple of o rings to help seal it in place. There are also baby bottles that are open in the middle to act as a "handle". I think its called a gripper baby bottles.

artesia (author)CitizenScientist2012-01-15

You should be able to buy glass bottles with holes in them at places like Michael's, Hobby Lobby, etc. =]

mr fat (author)2012-03-17

This is the best instructable EVER! Thank you for showing it to us all.

CatTrampoline (author)2012-01-15

Outstanding job! This would have been great for my high school and college physics classes, since neither school had much budget. I'll make one for my son when he takes college physics next year and send the link to his former science teachers.

I am sorry there are some "You did not invent magnetism" TROLLS harassing you over this posting. Please be assured that most people appreciate the information.

lilshelbybear (author)2012-01-15

Can you use a glass container or does it need to be plastic?

botronics (author)lilshelbybear2012-01-15

Glass is fine, but breakable. It will make an awful mess if it breaks.

ilpug (author)2012-01-15

We did this in science class but we used iron powder instead and it didn't work too well. I think the shredded steel wool is much better.

botronics (author)ilpug2012-01-15

You need long fibers so they can twist and align in the field like little compasses. Iron powder may rotate, but you won't notice it.

Tkdwn (author)2012-01-15

Nice job! Love it!

pie R []ed (author)2012-01-15

I applaud your ingenuity, and kludging ability! Wonderful instructable!

ssomealea (author)2011-11-26

Why does it works? could someone tell me , so that i can use this experiments to do in my science fair.

ssomealea (author)ssomealea2011-11-27

Thank you!!

botronics (author)ssomealea2011-11-26

Think of each steel wool fiber as being a compass. Each fiber will point along the lines of force when exposed to a magnetic field. The oil suspends each fiber and allow the steel wool pieces to rotate into position. Eventually, the fibers will clump and stick together as the field pulls them along. There are really no "lines of force" coming out of the magnet. The size of the "lines" depends of the size of the steel wool particles. The magnetic field travels through space and the fibers from the poles of the magnet.

rbessa (author)2011-09-21

Would it be possible to do something like this using iron oxide powder instead of the steel shavings ?

botronics (author)rbessa2011-09-25

I did some more searching about iron oxide and magnetic attraction. Not all iron oxide compounds are attached to a magnet or may be very weakly attracted. If you go to the art store, bring a magnet. The real trick is to use a fine steel wool, like grade 0000 and cut it up in small lengths. The fine steel wool will suspend for a long time in the oil. The fibers will line up along the lines of force. If you use too fine a particle, such as iron oxide powder, you won't see the lines of force. Its the shape of the fiber that shows the field.

botronics (author)rbessa2011-09-21

I heard you can remove the magnetic coating off of old VHS tapes and mixing that in oil. This makes a crude form of ferrofluid. Seems like a lot of work. Wikipedia say iron oxide is magnetic. So give it a try if you got some.

rbessa (author)botronics2011-09-22

I have tried dissolving old VHS tapes with pure acetone and it didn't work, but iron oxide is pretty cheap at any local art or drug store. However i don't really want ferrofluid, but a field viewer like you did in your instructable...i just thought that the iron oxide powder being more fine could give better result.

In any case i'll try it and say something about the results.

ezrablu (author)2011-08-04

I'm 53 yrs old and my father did this same thing for me and siblings when we were kids over 48 yrs ago so I think it's terrible for all of you negative finger pointers to even suggest this was copied is rediculous.....what's the purpose and where's the cause for such accusation? Most of the instructibles on this site would have to be removed because majority of this stuff was "invented" or done LONG before most of these people were even born. It's like the internet came along and everybody thinks it's the beginning of all truth and time LOL
My father also used give us magnets to roll in the dirt which collected iron and put it into babyfood jars. Ever seen magnetic etch-a-sketch or thing you run a magnet over the photo to put a beard or hair on the guy.
This is an excellent instructible and cool to see something I was shown by my father nearly 50 yrs ago. Thanks!

trooperrick (author)2008-05-20

wbeaty's youtube video Cite your source. Unless you got it from somewhere else. (I haven't seen it anywhere else...)

Otherwise, great job explaining!

CTGee (author)trooperrick2011-07-31

Magnetism has been seen in literary references as far back as the 4th century BCE in China... I don't think some guy that did a youtube video discovered this.

Spedy (author)trooperrick2008-05-20

Guess I'm not the only person that sees's work =)

But seriously, copying like this is something that REALLY gets on my nerves... Don;t do it.

Tool Using Animal (author)Spedy2008-05-20

Eveything's been done before, here it is in the Oct 93 Sci Am, The concept is also mentioned as an art form in one of Larry Nivens novels. Obviously everyone should do a journal search before posting anything.

I remember the Sci American article about mixing corn oil and corn starch to make a electrorheological fluid. That experiment was fun. Later I mixed a few drops of aluminum paint in kerosene in a 40 milliliter glass vial. Inserted 2 copper electrodes and energized them with a few hundred volts. Some of the aluminum will clump and dance in the fluid. The particles of aluminum will line up and create wonderful patterns. Rubbing the vial's glass surface with rabbit fur or just your hand will also create patterns that look like lightning on the glass. The kerosene is flammable, so there is danger, but I never had an ignition. Somewhere I have photos.

I'll have to try the kerosene and aluminum experiment, sounds like it would be pretty cool.

Did the experiment again. I mixed a few drops of silver paint in coleman fuel and placed it in a 40 mL sample vial. Then rubbed it with my hand. It still makes the lightning like figures on the side of the vial. If you run a charged comb or run your fingers along the glass the patterns change.

That's pretty cool, I'll have to tune up my electrostatic generator and give it a try.

Before I posted the instructable, I did a search on the instructable search engine and did not find one describing this project. This is not a formal scientific forum. This is a place for DIYers, hobbists and enthusiasts to share how to make and do things.

trooperrick (author)botronics2008-05-20

Don't get me wrong, I was just wondering if you honestly came up with this yourself. I agree, if you know something hasn't been post it, post it for everyone to see just cite your source if you took it from somewhere. Also, when I did this a while back, I found that the steel wool can sometimes get in your skin and it really hurts. Its fun to try and pick 50 little shavings out of your skin with tweezers. Maybe you could warn some people about that.

Why use tweezers when presumably if your doing this sort of thing you have a decent magnet on hand to pull them out with?

I guess I was wrong about clueless children posting about things they don't understand. Have you actually tried to pull bits of metal from your flesh with a powerful magnet?

yes I have and to be honest I normally reach for the tweezers before the magnet, but if I have many small metal things embedded in say my palm the magnet will get some of them with minimal effort, and save me digging around with the tweezers later.

I tried, but a lot of it stays in.

I have had the best luck with old(5") hard drive magnets.

botronics (author)trooperrick2008-05-21

I edited the instructable about clean up and keeping down the mess factor.

botronics (author)trooperrick2008-05-21

When you cut up the steel wool, do it over a sheet of newspaper and don't spill the clippings on the floor. I did this carefully in my hotel room on the dining table and cleaned any mess before the maid came. I didn't have any problems with my skin. I used 0000 extra fine steel wool, the courser stuff has a sharper texture. If this stuff was fiberglass, then you would have a real problem.

123tim (author)botronics2008-05-21

Indeed. I appreciate the time that you spent posting this Instructable. This purpose of this website is to instruct and inform others. You did an excellent job of both. I see no reason to cite another source for anything posted here. Everything in this Instructable has been around long before any of us were born. You simply taught us about it.

ham4fun (author)Spedy2008-05-23

So if someone(A) invents something which someone else(B) invented in the past, and the first (A) never had contact or any information about the first invention by (B), then (A) should never post his invention....... If it wasn't put here, I wouldn't have known about this method, but I was aware of a method we used at NCR with a magnetic powder in Alcohol to see how the tracks were positioned on magnetic tape. Just because you saw it somewhere else first doesn't mean I did!

Kiteman (author)Spedy2008-05-22

This is the sort of 'ible that gets "invented" several times independently. At my school, my HoD asked our technician to make one of these up before Christmas, because our bought version got broken. As far as I am aware, it was her own idea (she certainly does not spend her time browsing the web for things to make - she doesn't even have broadband).

There is no evidence that this is a copy of wjbeaty's work, but botronic never said it was his own idea. The use of mineral oil to suspend iron fragments is a logical result of the knowledge that iron rusts in water.

Even wjbeaty admits that there were Japanese versions in production before he invented his own version of this.

I personally have been accused of plagiarising in 'ibles because somebody saw it somewhere else, and even posted a link to it. They never thought that they might have been linking to my own, earlier posting of the same project before I discovered this site (even though both posts had the same name on them...).

slim_jim (author)Spedy2008-05-21

Since you decided to get crabby about sources, where is the proof that is the originator of this idea, anyhow? Why pick on this one guy? Go whine about the children posting bar tricks they don't understand. Or the amateur's "explaining" magic that that can't actually perform. Or the whacky guys demonstrating completely obvious ideas like "recycling". Who appointed you sheriff of Dodge, anyhow?

botronics (author)Spedy2008-05-20

I didn't get the idea from that source. But if anyone knows the origin of the idea, let us know to give due credit. I made one to show my kids about 20 years ago. Faraday, I believe, was the first one to use iron filings and come up with the idea of magnetic lines of force.

botronics (author)trooperrick2008-05-20

This was something I started to do many years ago to show my kids about magnetic fields. I used safflower oil with that one. Can't remember how I came about the idea, If you know of a source, let us know.

About This Instructable




Bio: I like to tinker and experiment with electronics, robotics, programming, and photography. Along with my latest interest in Steampunk.
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