A contact method for providing a constant, low-resistance connection to rotating electrodes is discussed. It is based upon the use of a consistent, solid/liquid contact between a stationary copper wire and a small mercury pool which rotates with the electrode. The design is shown to reduce the noise of electrochemical data. This is particularly important for experiments on oscillations and chaos in which analysis methods from nonlinear dynamics are employed. A second advantage of this design compared to a silver-carbon brush is that there is less change or drift in the measured signal during a long-term experiment.