This does not need supports whatsoever, and rafts are not recommended as this may affect the smoothness of the movement. If it is not moving smoothly, turn it quite a bit and it should free up. If not, then move the central body up and down, as there's probably some overextrusion (stringing) inside the gear mechanism. To get the part to move, push down from the top on the central part, and if the gears are stuck, push them upwards individually. If you wish to print with metal, then do the same process, but make sure to be extra careful with the gears. To get a minimal polished look just rub it with wire wool or sand with high grit sand paper, then if you want you can further polish this with cheap metal polish.
Note: resizing the model (especially downsizing) will affect movement in the design. If you wish to have a small version of the model, make the holes between joints bigger, or ask.