After my initial panic, I saw that the upper knife was broken. The top 'hook' had completely broken off. When the stump lowered, it was hitting the underside of the plate. I went and bought a new one $30 in Mexico City. Easily installed myself and everything is working fine. They didn't have the lower knife. But, I only have a little 'prick' on the edge. Nothing too serious. It seems to be working fine. The next time I am in the states, I'll pick up some extras if I can find them cheap. Thanks for the response. I appreciate the time you took. Merry Xmas and Happy New Year to all the Craftsters here.