Binding Basics

Sewn Binding Sewn binding is one of the oldest binding methods in history, and it is still the most durable form of binding for printed products today. Sewn binding is a process which utilizes thread sewn through printed signatures to bind them together. There are multiple types of sewn binding, but the most widely used method is Smyth sewing. Sewn binding is most often used for hardcover or casebound publications, but sewn binding methods can be used for softcover products as well. Sewn binding is commonly used for premium novels, illustrated books, children’s books, textbooks, yearbooks, large catalogs and coffee table books. Assembly required Industrial manufacture of sewn binding products varies between machinery and binderies, but the main processes of sewn binding are as follows. In Smyth sewing, which is also called section or saddle sewing, thread is sewn through the middle of each signature out and into the center of the next signature in a looping motion. In another method of sewn binding, called McCain or side stitching, thread is sewn down through the sides of all the signatures at once. Before the sewn book block is bound with a hard or soft cover, the threads on the spine are compressed to reduce thread buildup and force out excess air. Thread buildup occurs when the thickness of the book block is increased due to the alignment of the thread stitches, and this extra thickness is compressed either through nipping, a process where the spine is clamped and pressure is applied only to the spine, or smashing, where pressure is applied to the entire front and back of the book. In another process called backing, the book block is clamped between steel plates and the binding edge of the signatures are bent outward over the clamped edges, resulting in a spine that is wider than the rest of the

pages. This is sometimes necessary to shape the spine to effectively fit into its cover, and it creates a slight nailhead for the covers to rest on and impresses hinge creases that allow the book to open. The stitched book blocks are then sent to a binder where they are glued and trimmed. For case binding, the sewn book block receives bracket tape in addition to being glued off, and the book block is trimmed before casing in. For softcover binding, glue is applied to the spine of the book and the cover is attached before it is trimmed to size. In reference to sewn binding methods, gluing off is a process in which glue is applied to the spine of the book block to reinforce the thread sewing and the shape of the spine. Here, a three-knife trimmer, most often attached inline on the binder, is used to trim the head, foot and thumb edges of the publication. In the process of softcover binding, endsheets are not required and the binding is complete after the book is trimmed and the glue has dried. Through a special method offered for Smyth softcover books, there is a layflat option which does not glue the spine of the book block directly to the spine of the cover. This layflat binding method allows the pages to be more flexible to stay open for use of the product. Endsheets are usually white, but they can be made with colored paper and can be printed on to enhance the subject matter in the publication. If a casebound option is selected, an adhesive is used to coat the endsheets, which are attached to the outside pages of the book block and the inside of the hard or soft cover. The spine of the book block can be glued either to the spine of the cover or to backing material which wraps around the stitching to span between the spine creases. Although there are many ways to customize the sewn binding process, the end result will always be a durable and long-lasting, high quality publication. Endsheets are usually white, but they can be made with colored paper and can be printed on to enhance the subject matter in the publication.

Binding Basics

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