I studied the eigenfrequencies of a mirror mount designed with COMSOL.
I imposed fixed constraints for the base screws and for the screw connecting the base with the pedestal. Note that the central screw is connected to the base only for a small thickness, and the pedestal touches the base only with a thin annulus. This is in way to make a better model of the actual stress.
Shown in fig. 2 is the lowest eigenfrequency of the mount.
I' going to change the base and study the way the eigenfrequency vary, in way to find the configuration which minimizes the lowest eigenfrequency.