Thanks Jon for posting this. I find the gear in the gif fascinating with a worm to conical then a spur...what would that drive? And the way the fluid rides the crest of the worm and gears to a sphere at the top says a lot about the way the fluid works along the flux lines. Most of the general info out there is about the sensation and eye candy of it for demonstrations. I've seen and watched a bunch of the DIY Ferrofluid stuff but the commercially made fluid is a vast difference in physical properties. Also DIYing it is a bit dangerous for the home DIY IMHO, and very messy if not careful. The manufacturing/engineering/ChemE side of it is really being driven by the applications now, so there are vast array of base fluids and viscosity's as well as grain size and the surfactants used but it's still pretty pricey in my book. As application picks up momentum it'll come down as it has already, like most things. Applications are huge from speakers, MRI, heat transfer, bearings, seals, dampening and even propulsion etc. Space Propulsion really hasn't gotten off the ground as far as I know but maybe soon with these micro satellites.

To think it's been around for a half century and only now (last decade+) being used in commercial applications is a bit of a mystery. I didn't hear about it until the mid to late 70's and then later saw some stuff in trade magazines. Wiki is a good start but a tip of the iceberg to what's gone and going on out there...like carbon nano tech and 3D chip tech. Non magnetic mechanical pumping this fluid is a field I am interested in.

Thanks again for putting these up for the Forum. Looking forward to what every you find in the future. ~PJ