Abstract: A lawnmower blade assembly, including a replaceable cutting edge insert and method for its use. The cutting edge insert is disposed within a recess of a support member at each end of a centrally rotatable main blade. The recess has a blunted front edge, a back shoulder, an outside shoulder, and a passage for an insert release tab. Two threaded preset Allen bolts, protruding from the recess floor, are permanently locked into position. The bolts are not specifically designed to carry the load of the rotating lawnmower blade. The back and outside shoulders of the recess provide most of the force necessary to retain the insert against rotational and centrifugal forces. The cutting edge insert, having substantially the same profile as the recess, and having slotted holes for reception of the bolts, can be slid in and out of the recess. An interference-type friction fit exists between the preset bolt head and the floor of the recess.