>Weight makes it continue to spin too long.
> So what I gather, is a guy could put a good sized
> weight on the shaft to create inertia and give a
> perception of quality, then use optical interrupters
> to capture disc position?
Better a good fit of a shaft and a bushing with oil between, like
a 10-turn pot knob. This gives you resistance for fine setting, and
you can spin it relatively fast still.
ST