Abstract: The automated floor sander includes numerous devices and mechanisms to facilitate the task of the operator of the machine. The machine includes a variable speed drive mechanism, enabling the operator to select the desired travel speed over the surface in order to optimize results. Another feature is the automated sanding drum lifting and lowering mechanism, which automatically raises and lowers the drum if the travel speed of the machine respectively decreases or increases below or above a predetermined point. A manual mechanism for controlling drum height is also provided. Yet another feature is a novel mechanism for automatically centering the sanding belt on its tension roller, which mechanism greatly reduces wear and tear on the belt and friction in the system when the belt reaches one end of the tension roller. These mechanisms may be incorporated separately from one another or in combination in a single machine, as desired.