A surface finish measuring device for gear teeth. The device includes a probe for tracing an involute surface such of a gear tooth, a computer numerical control (CNC) machine for receiving perimeters relating to the geometry of the structure being measured and rotating the structure at a preferably constant angular velocity; and a computer for determining which measured points on the involute surface are to be used by a display device such as a strip chart recorder to graphically illustrate, in a highly magnified fashion, the topography of the involute surface being measured. The present invention overcomes the problems associated with the rate at which the distance between consecutive measurements changes when measuring an involute surface to provide a collection of relatively evenly spaced measurement points. The relatively evenly spaced measurement points help to provide a more accurate graphical display of the topography of an involute surface when plotted out on a graphics plotter or other display device.