Abstract: An improved cutter blade assembly for lawn edging machines, the improvement comprising two cutting blades having the central portions of the first and second blades nested flat face against flat face and mounted on a powered drive shaft, the blades extending oppositely and outwardly from the horizontal drive shaft in a plane normal to the axis of the drive shaft. Each of the cutting blades preferably contains a series of progressively spaced, stepped mounting holes, a series of stepped locking holes, and a locking dog to provide an adjusting means for extending the combined length of the two cutting blades to compensate for wear. As the diameter of the cutter blade assembly is shortened from wear, each cutting blade may then be disengaged from the drive shaft and moved radially and oppositely outward and may then be re-engaged onto the drive shaft through the next appropriate mounting hole. Thus, the cutter blade assembly may be restored approximately to its original cutting diameter.