Introduction: How to Make Magnetic Slime With Iron Filings

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What's better than normal slime? Slime you can manipulate with a magnet!

In this instructable, I'll show you how to combine a simple school glue slime with iron filings for an especially strange slime experience. :D

See the differences in color in the slime? This occurs when the slime and filings separate due to the power of the magnet. It's pretty mesmerizing!

P.S. This slime is a variation of my saline solution slime. Want more slime recipes? Check out recipes for homemade slime.

Step 1: Tools + Materials

To make magnetic slime, you'll need the following things:

  • Slightly less than 2/3 cup white school glue
  • 2 teaspoons contact solution (must contain boric acid)
  • 1 tablespoon baking soda
  • 1-2 tablespoons iron filings
  • Rare earth magnets
  • Bowl and spoon for mixing
  • Measuring spoons and cups
  • Plastic baggies for cleaner play

I recommend using plastic utensils if you can - the iron filings can cause metal utensils to rust if not cleaned quickly enough.

In addition, you can play with this slime by placing it in a plastic baggie and running a magnet along the plastic. That way the slime doesn't eat your magnet and you don't have to spend a while digging it out. :D

You can also add a small amount of food coloring to this slime, but I prefer to leave it plain. It's easier to see the iron interacting with the magnet that way.

A note about magnet safety: always supervise children around rare earth magnets. Do not allow magnets to bang together as they may shatter. Be careful playing with multiple magnets as they can pinch skin. Do not allow magnets in or around mouth, nose, ears or eyes.

Step 2: Measure Out Your Glue

Measure out slightly less than 2/3 cup of white school glue. You may want to use a spatula or popsicle stick to get the glue into a bowl. :)

Step 3: Measure and Mix in the Iron Filings

I decided to use 2 tablespoons of iron filings which made for a VERY strong slime. If you have fairly weak magnets, I recommend staying with 2 tablespoons.

If you're using a strong rare earth magnet like I am, you can scale down to 1 tablespoon of iron filings and still see great results!

Stir the filings into the glue until you don't see any solid black or white areas in the mix. Make sure to scrape the sides and bottom of the bowl to get all the filings.

Step 4: Add the Baking Soda

Now you'll want to add in 1 tablespoon of baking soda. Stir until it's completely mixed in. You don't want any baking soda lumps!

Step 5: Add the Contact Solution and Stir

Now the real magic happens!

Measure out 1 teaspoon of contact solution and mix it into your slime. The slime will begin to thicken and pull away from the sides of the bowl.

Measure out a second teaspoon of contact solution and mix that in. Now the slime will really start to form! Keep mixing until the slime pulls away from the sides of the bowl as seen in the last photo.

Step 6: Knead the Slime Until It Feels Right

Pull the slime out of your bowl and knead it in your hands until it's not sticky - this may take a couple minutes! You'll know it's right when the slime doesn't stick to your hands or work surface but is still elastic and stretchy.

Step 7: Play With Your Magnetic Slime!

And the best part: playing with your slime! Magnetic slime is amazingly fun to play with and has a mind of its own.

Touch your magnet to the slime and the slime will instantly begin climbing up the magnet. The magnet will pull the iron filings to it while the white glue slime separates and is pushed to the surface.

It can be a little tricky to clean off the magnet, but I found pulling and scraping the slime off in a large piece to be easiest! I also rinsed my magnet in a bit of warm water to remove the very last of the glue when it really needed it.

Fun things to try:

  • Throw a magnet into the middle of the slime
  • Place magnets around the edge of the slime and watch it stretch out
  • Attach something small and metal to your magnet and see if the item can attract the slime

Step 8: Cleaning Up Your Slime

As stated on the tools and materials step, this slime can be a little messy due to the iron filings. I've attached a photo of the slime in a plastic baggie five days after I made it.

When you make my basic slime recipe, it's normal for the contact solution to separate when you store it. In this case, the water in the contact solution reacts with the oxygen and iron filings in the container leading to rust.

Try to avoid storing it - it's pretty stinky and will stain surfaces. Instead, throw it away in a waste container when you're done experimenting!



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