Ferrofluid makes the lava lamp cool again

A new desk lamp is taking over from the lava lamp -- by replacing the boring old wax lava with interactive magnetic fluid.

Michelle Starr Science editor
Michelle Starr is CNET's science editor, and she hopes to get you as enthralled with the wonders of the universe as she is. When she's not daydreaming about flying through space, she's daydreaming about bats.
Michelle Starr
3 min read

Kyle Haines

Magnetism is one of the most fascinating phenomena on the planet, and there are innumerable magnetic desk toys that speak to our -- cough -- attraction to these objects. One of these that has emerged in recent years is ferrofluid -- a thick, oily fluid containing nanoscale magnetic particles, suspended in a bottle of water. Moving a magnet around the outside of the bottle attracts and repels the ferrofluid, allowing the user to create shapes or bounce it around in the bottle.

To many, this resembles a lava lamp, with its globules of warm, molten wax moving around in water in response to the glow of an incandescent light. It was this that led creator Kyle Haines down the path of creating a new type of lamp -- one that contains magnetic fluid that can be interacted with, rather than blobs of wax that can only be passively observed.

"I noticed that whenever I showed ferrofluid to people, a fairly common reaction was to compare it to a lava lamp. In fact, some press would cover a ferrofluid project and say things like 'this is the next lava lamp'. I also noticed comments on articles where people stated that they thought ferrofluid displays should have a passive function like a lava lamp, where they move on their own," he explained.

"I started thinking about what it would take to actually turn ferrofluid into a working motion lamp and realized that it's actually very well engineered for the task (in theory). So, I started experimenting until I got it right."

Ferrofluid moving in response to the heat of the incandescent bulb. Kyle Haines

His creation -- called Inspiration, currently seeking funding on Kickstarter -- is based on the same principle as the lava lamp. As the incandescent light source at the bottom heats the ferrofluid, it forms globules and will float to the top of the lamp, into the cooler water, which in turn will circulate the globules back down -- much like how a traditional wax lava lamp works.

The big difference, of course, is that you can use neodymium magnets to attract or repel those globules of ferrofluid -- interacting with the material inside the lamp. Achieving a lamp that can do this was no mean feat, and Haines has spent three years conducting research and development for Inspiration.

"The biggest challenge with any ferrofluid display is keeping the ferrofluid from sticking to the walls. This requires very complicated chemistry that many people have unsuccessfully tried to solve. I can't go into how I solved this problem because it is a bit of a trade secret," Haines -- who works in nanofabrication -- said.

"As for getting the ferrofluid to 'flow' in the motion lamp, it was actually surprisingly simple once I figured out how to keep it from sticking to the glass. It's really just a matter of 'tuning' the density of the two liquids to be very closely matched, while keeping the ferrofluid just slightly more dense."

Kyle Haines

The aim of the project is not just to create a really awesome lamp -- although it's pretty danged awesome -- but to encourage curiosity and education about nanotechnology, an emerging technology with potential applications from medical through to industrial manufacturing through to robotics.

"Ferrofluid is an example of nanotechnology and, when presented in the right manner, is very successful at creating interest were there was none before," Haines wrote on the Kickstarter campaign. "This is because of natural curiosity. I want to encourage that curiosity as well as the imaginative thinking that comes with it. I want to remind people there's still so much to discover and explore."

The Inspiration is being offered as a reward with a project pledge of $149, including magnets, with an estimated delivery date of August 2015. Head on over to the Kickstarter campaign to check it out and pledge your support.