A method for tuning a spring element (106) used in a resonant driving system for an appliance such as a power toothbrush, which includes a work piece and which has a driving frequency, includes the step of measuring the frequency dependent amplitude of the work piece, which vibrates by means of operation of the spring element, wherein the measured frequency of the appliance is either above or below a driving frequency. Furthermore, the spring rate of the spring element is changed, as a result of which its resonant frequency is changed, sufficiently that it closely approximates the driving frequency of the appliance. In a situation in which the spring rate of the spring element is decreased, this can be done by removing a portion of the spring element.