I don't know if this binding is really called a zigzag stitch but since it looks like what a sewing machine can do I am going to call it that. I may have told you that I am in the process of cleaning my studio/office. This means that I have to free up space in the garage for many items. I was going through my flat file drawers and found many papers made many years ago. I am using them left and right to make new books.