I have a Starrett Speed Indicator that must have belonged to my father or grandfather on the farm (checking machinery speeds?).
It is like the top one. I have no instructions or manual for this (or any of the rubber tips). Any of you guys use one before? I assume one must use a stop watch or some other means of timing while counting turns. When you stop then graduations allow counting the partial turn for the last digits of the speed? Any help would be appreciated since I am somewhat math challenged and can't figure it out just by looking at the scales.