I built just a long pendulum in my house in order to start looking at a simple Foucault pendulum "prove the earth moves" event at the science museum I'm helping to start here in Pensacola. It gave me a nicely reliable movement that seemed to show the pattern I was looking for. Every time, it traced out a clockwise set of stripes in some sand. But, when looking it up online and researching Foucault's own work, there is a lot of information about a careful release mechanism. How careful do I need to be? I don't care if mine damps out pretty quickly, as long as it shows that we are experiencing acceleration due to the rotation of the earth. TIA!