Hello, folks. Apologies first, because I still need to formally introduce myself to everyone somewhere on here; but I just wanted to mention something that all of us who are the mechanically self-reliant types might forget to consider and overlook because of our own enthusiasm we put into our penchant for design improvements to various products that we believe have performance/poor design that need upgrading. My dad was a professional welder and Journeyman sheet metal worker that could always handle any mechanical/electrical task at hand. But one day I stopped by his home shop and he proudly showed me his just completed project of that morning; he had suffered the same sort of damage to six mower blades and in short order expertly welded some high carbon tooling to each cutting edge. Those machine tooling cutters had been kicking around that shop since I was a kid and had been taken off some sort of joiner type wood working machine. They were about ¾ inch wide and 6 inches long. Well, his complexion turned ashen when I mentioned they could disintegrate into shrapnel when striking an object. I knew the faces of his grandchildren had immediately come to his mind and his demeanor reflected that he had possibly avoided a tragedy. A second opinion never hurts when moving parts are involved. Those factory blades are performing exactly as designed and should not in the most extreme impacts at high speeds disintegrate and shed lethal projectiles.