Abstract: In the case of a method for balancing rotors, more particularly tool holders of machine tools, the imbalance of the rotor is ascertained in a computer, in terms of size and direction, of a balancing machine and is compensated by spreading at least two balancing elements with a predetermined imbalance into suitable positions of adjustment. Firstly from the measured imbalance of the rotor and the size of the imbalance of the balancing elements the position of adjustment of the balancing elements is determined and then the rotor of the balancing machine is turned until a balanced position is reached, at which the position of adjustment of the one balancing element is at a predetermined position in relation to the balancing machine. When the rotor is located in the balanced position, a visible marking is projected onto the balancing element. The balancing element is then set in its position of adjustment by bringing a mark provided on the balancing element into alignment with the visible marking.

Abstract: In the method for balancing a body of revolution using a balancing machine which comprises an adjustment means for positional resetting of compensation masses, firstly the compensation masses are brought into zero positions thereof, wherein the imbalance vectors produced thereby cancel each other out. Then in a known manner the imbalance vector VI present is measured in terms of its magnitude and direction. After this at least one of the compensation masses is reset by shifting through any desired angle &agr; or by changing its distance from the axis of rotation, an additional imbalance being produced with a calibration imbalance vector V2. After this in a known manner the overall imbalance vector V3 present is measured in terms of its magnitude and direction and from the imbalance vector V1 and the overall imbalance vector V3 the calibration imbalance vector V2 is calculated from V2=V3−V1, the system comprising the balancing machine and the body of revolution being calibrated.