Only when I've forgot to lock it closed after I made my cuts! :shock: I'm always reminded of the story of a woman who left her rotary cutter in the unlocked position, knocked it off her table and got a nice big slice across her unprotected bare foot!!!!!! :shock: :shock: :shock: She had to be rushed to the emergency room and had many, many stitches!!!!! After I read that I started locking my cutter before I lay it down!!!!! 8-)