Ferrofluid display

[Lance]

I am trying to make a ferrofluid display cell with 1oz plastic bottles and water.

 

The water will not mix with the ferrofluid (its oil base) but when a strong magnet is brought close the ferrofluid flows to the edge and coats the plastic so when the ferrofluid is no longer there the plastic is still black.

 

I have had some amount of success with mixing soap with the water but that still doesn’t last long. A thicker solution of soap and water also helps but that minimizes the length of the spikes.

 

Any ideas?

 

Edit:

You can see a display cell at:

https://www.teachersource.com/catalog/index.html

You must do a search for "Ferrofluid Preform Display Cell"

 

The picture does not show a very strong magnet and it’s not that close either so it’s impossible to tell if it would coat the plastic.

[Lance]

Anybody?

 

*goes back to mixing random chemicals with ferrofluid*

[Dave]

I suppose you just need to find the right mix. They probably spent quite a while trying to get the right one themselves.

[Dave]

I've been reading up a bit on them, and they sound quite interesting. However, I'd hazard a guess to say that the ferrofluid displays are made with some kind of oil and extremely fine iron filings (although I could be wrong of course). I don't know whether you made your own ferrofluid or not, but this could be causing your problem.

[Lance]

No, it’s High quality Ferrofluid. It's all made by one company so it’s the same type in the picture.

[Guest ferrodave]

Hi Lance,

Have you gotten any further since you last posted these comments?

 

What are you trying to make as your end product? What will you use your own display cell for?

 

David

[Lance]

Hi Lance' date='

Have you gotten any further since you last posted these comments?

 

What are you trying to make as your end product? What will you use your own display cell for?

 

David[/quote']

 

Nope, I suppose glass might work better but I don’t have any glass bottles. My end project will be the display cell it self. If the ferrofluid didn’t coat the bottle then I might think about reselling it, although if the answer was posted here it would become common knowledge and I would gain competition.

 

The cell in the link in post #1 cost $20 which is a lot to pay for a few drops of ferrofluid and a plastic bottle.

[Lance]

Well I got an email from ferrotec today....

 

"Dear David:

 

The display cells contains an R&D ferrofluid that is not sold in bulk. It is $10.00/ml and our minimum order is $100+ on a Visa or Master Card.

 

Best regards,

 

Diane"

 

If I bought the same amount of this fluid as I had bought the other it would have set me back $10,000. Oh well, It looks like I wont be getting any more money out of ferrofluid, for the time being anyway. At least I made back more than I paid for it.

 

It doesn’t matter anyway, if I had figured it out I may have made a few dollars before somebody else figured it out and undercut my prices. I'm not sure why I made this thread in the first place. Of course I could be lying. I could have figured it out and at the moment mass producing millions of ferrofluid display cells.

 

I suppose I should have sent the email before wasting all my time trying to figure it out. For all I know it would be violating some patent anyway. Bleh.

[jsatan]

I've got some water based stuff, and to any one reading this DO NOT BUY it is a waste of money, doesnt act like the oil based stuff,

[Lance]

How is it different?

[jsatan]

when you place a magnet near it, it doesnt show field line it just blobs together.

[jsatan]

I've just read soem where that you can use alcohol,

[sfpublic]

(Distilled) water works with Ferrotec (Ferrosound EFH1) to some extent, but vodka* works better and does not mix with the water at all, although a small amount of carrier will separate from the ferrofluid and float. Like the original poster, this is an oil based ferrofluid and therefore attracted to plastic. A smooth glass cell works quite well, but some small droplets of ferrofluid are likely to stick to the odd imperfection regardless. Just be sure to pre-wet (i.e; fill) the vessel with your filler fluid before adding the ferrofluid. A stoppered bottle with seal is best, as trapped air can complicate things.

 

*Essentially pure ethanol-water mixture, my best guess from the MSDS for an existing commercial cell, of which there are three suppliers

[explokate]

Any updates from anyone who has tried it? We'd like to make a demo cell, just for fun. In particular, if the FerroTec EFH1 is put in vodka as the last poster suggested, how long does it stay pretty? Does it mix or degrade eventually? Any expert advice out there from others who have tried this in the meantime?