Method of improving the pivoting of a wheel set

A method of improving the pivoting of a wheel set or of an equipped wheel set for a scientific instrument or timekeeper, including at least one arbor arranged to pivot or oscillate about an axis of oscillation aligned on an wheel set axis formed by the axis of said arbor, wherein:

• performing static balancing of said wheel set to bring a center of gravity onto said wheel set axis;
• determining a desired value for a resulting unbalance moment of said wheel set about said wheel set axis, corresponding to a predetermined desired divergence between a first principal longitudinal axis of inertia of said wheel set, and said wheel set axis;
• setting in rotation said wheel set at a predetermined speed about said wheel set axis, the resulting unbalance moment is measured with regard to said wheel set axis;
• making an adjustment to a value of the resulting unbalance moment of said wheel set about said wheel set axis within a given determined tolerance with regard to said desired value;
• performing said adjustment by machining both sides of a median plane including two secondary axes of inertia of said wheel set.