[NileRed] admits that while ferrofluid has practical uses, he simply wanted to play with it and didn’t want to pay the high prices he found in Canada. A lot of the instructions he found were not for making a true ferrofluid. He set out to create the real thing, but he wasn’t entirely successful. You can see the results — which aren’t bad at all — in the video below.
We’ve always said you learn more from failure than success. The process of creating ferrofluid involves two key steps: creating coated nanoparticles of magnetite and removing particles that are too large or improperly coated. After the first not entirely satisfactory attempt, [NileRed] tried to purify the material using solvents and magnets to create better-quality particles. Even the “bad” material, though, looked fun to play with along with a powerful magnet.
You’ll see that the material is clearly magnetic, it just doesn’t spike like normal ferrofluid. [NileRed] had commercial ferrofluid for testing and found that if he diluted it enough, it behaved like his homemade fluid. So while not conclusive, it seems like he diluted the batch too much.
We hope to see a better batch from him soon. The base material he used for the first patch was homemade — he covers that in a different video. However, for the second batch, he is going to start with commercial ferric chloride — what we know as PCB etchant.
Even though the experiment was not entirely successful, we enjoyed seeing the process and watching the performance of both the homemade batch and the commercial ferrofluid. He’s getting a lot of advice and speculation in the video comments, and it is very possible a Hackaday reader might be able to help, too.