Anytime a pattern of holes exists, either on electrodes or on common parts such as speaker grills, the hole centers must be referenced. However, when the part shape is contoured, there is no true circle to provide the center point. This presents a unique challenge, but one that Cimatron can solve with a special selection filter. While in the Point function, open the filter dialog and set it to Center and 3D Cone Edge. This filter not only allows for a box selection of multiple curves, but can also determine the true centers of 3D curves that are not arcs.