Certainly a 7.4mm wide mirror can't really move a 5mm beam. It barely fits on the mirror at rest!
The 0.014g * cm^2 is the inertia of C506 rotor (Magnet, Output and PD shaft, and two bearings) with no mirrors.
For approximation, our mirror inertias are (roughly) as follows.... of course the substrate changes this somewhat
3mm 60 degrees - 0.0027 g*cm^2
4mm 40 Degrees - 0.007 g*cm^2
5mm 60 Degrees - 0.013 g*cm^2
6mm 50 Degrees - 0.022 g*cm^2
8mm I cant remember off the top of my head. Maybe around 0.100 g*cm^2?
10mm 40 degrees - 0.160 g*cm^2
I also have some spreadsheets I made that I can calc theoretical scanner performance, based on load applied. Basically frequency vs angle, for a sinusoidal waveform. This is represented in graph form on the backs of all SM datasheets.
Sincerely,
Ryan Smith
ScannerMAX Mechanical Engineer
ryan {at} scannermax.com