How To Make Ferrofluid: Cheap, Fast and Easy

Ferrofluids are really cool. They are liquids that change properties when introduced to a magnetic field. They have been a big part of some recent research on things varying from space shuttles to body armor! Usually they are very expensive and complicated to make, but we have found a way to make a simple mid-quality ferrfluid out of household items quickly, easily and very affordably. You probably have all of the materials at home, and it can be done with little to no effort or time.

1) Collect your materials

---500ml/16 fl. oz. Acetone.
Acetone is high flammable so be careful with it. You can get it at most department stores or beauty supply shops..

---10 music tapes or 4 video tapes.
Music or video records tapes. You can get these oldies almost anywhere. You probably have a few laying around your house.

---5ml/0.2 fl. oz. Cooking oil.
Every house has secret room...The kitchen...

---1 big strong magnet.
You can get it from any speaker in your house... Be ingenious... Or look online for some neodymium magnets.

2) Prep your tapes

Tape:
The tape itself is actually very simple. It consists of a thin plastic base material, and bonded to this base is a coating of ferric oxide powder. The oxide is normally mixed with a binder to attach it to the plastic. It also includes some sort of dry lubricant to avoid wearing out the recorder.

Ferric and iron oxides:
Iron oxide (FeO) is the red rust we commonly see. Ferric oxide (Fe2O3) is another oxide of iron. Maghemite or gamma ferric oxide are common names for the substance.

Procedure:
We need separate Ferric oxide from plastic tapes. Acetone will melt the binder and separate Ferric oxide. But first we need to smash and break tapes!

3) Melt Binder and Separate Fe2O3

Melt a glue:
Find a big bowl. Put all tapes in it and fill the bowl with acetone. Wait few hours. You can close bowl with something for a better effect. Make sure that you are in a well ventilated area away from open flames! Acetone is dangerous- read the bottle.

4) Collect the ferric oxide

Collecting ferric oxide:
Get a magnet. Roll it with paper (paper is needed to separate ferric oxide from magnet). Collect all your Fe2O3. Let it air dry and put it in a safe place.

Repeat step 3:
If all of the oxide did not separate from the tape, you can repeat the procedure with acetone few time to have a better effect.

5) Make a substance

Mix with oil:
Mix three parts ferric oxide with one part cooking oil. If it's to viscous add a drop of water and a drop of dish soap and mix everything again. It will be good.

6) Magnetize the liquid.

Remember to strongly magnetize the liquid. The stronger magnet that you use, the better the effect.

Voila! You are done. You have a mid-quality ferrofluid that only costs about a dollar to make. Have fun!