Neil Fraser’s Lava Lamp Centrifuge is 10′ across, weighs 50 pounds, and spins at 42 rpm generating 3 Gs. It uses a Nexus One’s accelerometer to measure g-force. Excellent!

Will lava lamps work in a high-gravity environment such as Jupiter? This topic spawned considerable lunch-time discussion and no clear consensus emerged. Most people initially assumed that the wax would sink to the bottom and wouldn’t cycle, but as the physics was examined in greater depth this assumption became difficult to defend.

To find out how lava lamps behave in super-terrestrial gravity, I built a large centrifuge in my living room. This was intended to be a fun activity for a long weekend in January. However the project’s size and power requirements were well outside my previous experience. Thus it was a rich learning experience as I encountered one metal-shredding and wire-melting failure after another. In the end, perseverance paid off and I obtained the answer to the original question.

[Thanks, hectocotyli!]

14 thoughts on “Meccano/Nexus One lava-lamp-testing centrifuge!

  1. The last remaining question is, how do you answer your phone at 3G of centrifugal force?

  2. Am I the only one noticing that the lava lamp is … upright? Thus perpendicular to the “gravity” generated by the centrifuge? I don’t think the experiment is valid unless you tip the lamp. Also you need to account for the extra G of downward force due to Earth’s gravity.

    This demonstrates that if you tipped a lava lamp on its side on Jupiter…

    1. This is the coolest thing I have seen for a long time. And he used Meccano. Old school Meccano!

      The lamp is held in a rotating housing so it tips as the centrifuge spins up so the bottom of it always points down (out).

  3. Im no physicist, but isnt is true that gravity and density are completely separate of each other?

    like, even if the gravity is kicked up to 10x, wont the oil still be less dense than the water? (or the other way around, whatever)

    1. I can’t work out in my head if there should be a differential rate for buoyancy effects or not.

      There was a pronounced Coriolis effect though, or at least there seemed to be.

      Really nice build. Wonder how he maintained 110V on the swingarm, brushes?

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My interests include writing, electronics, RPGs, scifi, hackers & hackerspaces, 3D printing, building sets & toys. @johnbaichtal

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