A third option for binding books is saddle stitching. Children's books, calendars, and magazines are most often saddle stitched. A book book must be relatively thin to be saddle stitched.
In the Saddle Stitching operation the signatures arrive at our New Muller Martini Saddle Stitcher, where they join together with a cover (if required). Here the signatures and cover are stapled and trimmed to form a finished book or calendar.
The folded signatures are first
loaded into pockets on the Stitcher. The machine will pick up the
signature from the bottom of the pile with vacuum. Fingers will grab the
signature and pull it down around a drum. The signature opens in
the middle and is set down on a track that carries it forward
toward the cover. If several signatures make up the book, they
are fed into the pockets in the correct page sequence.
The signatures are collected one on top of another and delivered to a track that moves the sections forward towards the cover. The cover feeder pocket is different then the signature pockets in that it feeds the flat cover through scoring wheels. It then folds the cover and drops it on top of the signatures on the track below.
After the cover and signatures have been collected on the track they move to the stitching heads. Depending on the length of the spine, either two or three staples are used to stitch the whole book together through the spine. After stitching is complete the book is transported via the track and belts to the Three Knife Trimmer. The trimmer is set to the size and specs of the book and is trimmed on the top, bottom and foredge. Emerging from the trimmer it is a complete book and ready for packing. This whole process happens at 6000 - 9000 cycles per hour.
