A method to model mechanical systems with multibond graphs is described. The method is based on the description of the vector velocity relation of a moving point in a rotating system. This relation is incorporated in a bond graph. Since bond graphs are based on the power conserving concept, the force or momenta relations are then available too. By repeating the same bond graph structure for every point (which is of interest within a chosen coordinate frame), where each point has the same rotational velocity, a systematic way of modelling mechanical systems is achieved. It is explained how connected mechanical linkages have to be handled. Two simple examples are given.