Magnetic Silly Putty




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Thinking Putty (also known as Silly Putty) is a silicone polymer children's toy. Silly putty is fun because it has some unique properties: it is viscoelastic, meaning it can be stretched and shaped and mashed back together again; and as its apparent viscosity increases directly with respect to the amount of force applied (read: it can be torn or shattered with impact). Silly putty is a non-Newtonian viscoelastic polymer, better characterized as a dilatant fluid. Also, it bounces.

Ok, enough science. I'm sure we've all played with Thinking Putty in our youth, but how about magnetic silly putty?

By adding a ferrous component to an already wacky toy we can keep all characteristics of the original putty, but now have the additional dimension of magnetism! I've seen magnetic thinking putty for sale on otherwebsites, but I'll show you how you can make your own for a fraction of the price and in about 20 minutes.

Enough talk, let's make some magnetic putty!

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Step 1: Tools + Materials


The secret ingredient that makes the putty magnetic is an iron oxide powder, which is ferric (magnetic). Ferric iron oxide is a fine powder used as black pigment and can be found at art stores. If your local artist supply store doesn't carry it, you can always purchase it black iron oxide powderonline.

Step 2: Prepare Putty

Start by clearing a space to work, make sure it is well ventilated. Iron oxide powder is very fine and inhaling it is probably not such a good idea. Put on your gloves and face mask before you begin.

Open the thinking putty and remove from the container. Work the putty in your hands a little to warm it up, then stretch it out like a sheet and lay it on your disposable work surface (sheet of paper or paper plate).

Step 3: Add Iron Oxide

Thinking Putty comes in different sizes, depending on where you purchase it. I found mine in a local toy shop, it comes in an egg-shaped container and is about 24 grams (0.8 oz).

For this size, I used about a tablespoon of iron oxide, you may require more or less depending on your putty size and amount of magnitism desired.

Carefully spoon the iron oxide into centre of putty sheet, then close lid on iron oxide powder to reduce excess iron dust escaping.

Step 4: Work It

Gently fold edges of putty sheet into centre and work the powder into the putty. Go slow, the powder produces lots of dust.

After a minute of massaging the putty it will lose it's colour and begin to look black as pitch. Keep massaging putty for about 3-4 minutes.

Step 5: Experiment and Have Fun!

That's it, you're done! Grab your magnet and start experimenting with your new magnetic putty.

You can stretch out a strand and make it follow your magnet, you can polarize your putty to work as a magnet itself, and then there's the classic of placing the magnet directly on the putty and watching it envelop the magnet. There's plenty of fun to be had, check out the video I made with some of the fun you can do.

Some frames have been sped-up to illustrate magnetic properties.
Of course, aside from being magnetic your putty still retains all the properties of the original Silly Putty.

Putty has been known to leave a residue on some surfaces, even more so with the iron oxide powder. Use caution when playing with your magnetic putty.
If you get magnetic putty stuck to fabric you can try placing the magnet on top of the fabric and the putty may work it's way out (wait 24 hours). Alternatively you can apply rubbing alcohol to area and work out the putty, try a concealed test-area first. WD-40 may also work. If all else fails, take the fabric to the dry cleaners and tell them it's a silicone-based stain.

What are you waiting for? Get going and make your own magnetic putty!
Place a picture or video of your version of magnetic putty in the comments below and earn yourself a digital patch and a 3-month Pro Membership to!

Have fun!
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303 Discussions


I'm sorry to be a party pooper but there are some very serious health hazards to be concerned about when handling black oxide of iron! Please check out this health hazard warning before trying this experiment and use a breathing mask if you do plan on doing this for sure!!

It can even change your eye colour after some people have been exposed!

Follow this link for more info on the health hazards of using black iron oxide.

5 replies

Reply 3 years ago

You realize the link you sent is for Iron Oxide, which is just plain ole rust, created naturally. Granted this is the same name (contains similar chemical composition), it is also a refined product which is produced artificially for the purpose of being a pigment.

Still, like any fine particulate, not good to be breathing in without proper respirator/mask etc.

Mark 42ccopyrites1986

Reply 1 year ago

"Still, like any fine particulate, not good to be breathing in..."

Have you seen the "Will it Blend" series on YouTube?


Reply 3 years ago on Introduction

But it's only the powder, right? Say, for ferromagnetic fluid, it's going to be suspended in a bottle of liquid. And with this silly putty, it's mixed in. Plus, why would you ever make repeated contact with the powder in the first place? It has no use by itself. You only need it to make whatever, and beyond that point it's safe. At least that's my hope. I don't want to order a big jar and mix it in only to find that I'm gonna up and die from handling the stupid stuff. :(


4 years ago

Will a Home Depot or michaels have the iron oxide? When you call, the kids answering say they don't know what it is

3 replies

Thank you so much, I (unfortunately) figured that out after driving back n forth in rush hour traffic lol.. I guess on to new idea for project and try that when not in time crunch..THANKS AGAIN!!


1 year ago

You can get black iron oxide at any hardware store, in the cement colorant section.

The black one is iron oxide, and it's quite cheap.

Mark 42

1 year ago

I wonder if using an old style ferro magnet and sanding it into powder would be stronger than iron oxide. A belt sander could sand a few magnets into power fairly quickly.


2 years ago

This is actually a product that you can buy - it's called Crazy Aaron's Thinking Putty, and they also have a magnetic version of it. Just saying... Crazy Aaron have a whole lot of cool Thinking Putty so check it out on Vat 19 or on their website.

PS: this is not a promotion

3 replies

Reply 2 years ago

I made this project before magnetic putty was commercially available, the way it is now.

Also, my buy when you can make? :)


Reply 2 years ago

Sorry, didn't know that you made it before it was available commercially. Anyway, I do like the idea, and I'd like to try it. Btw is the toner thing easy to buy or do you have to buy it from somewhere online?


3 years ago

I really do love this, but it's just not safe for little kids in my mind not for a whole bunch at a party anyways! I think for an at home project with your kids yes because you can just make it when there in bed and let them play with it the next day! but there is also other ways to make this which are safer! but still thanks for the post it's great!


4 years ago on Introduction

I also made two fluorescent colors of putty that glow nicely under black light. I rolled the putty into a ball and set it on top of a plastic container with a powerful cylinder magnet at the top and let it sit for hours until a nice 'bloom' developed. The third one is a ball placed directly on top of a 2" square neodymium magnet.

1 reply

Reply 3 years ago

These look amazing! Mind sharing your process for making them luminescent? It's really cool.

Thanks for sharing your pictures, enjoy the Pro Membership!