Book Pages: Sewn or Glued
The page blocks of hard-cover books are usually put together in one of three ways: sewn signatures, glued signatures, or glued individual pages. Because sewing is more expensive than gluing, almost all mass-produced books are put together with glue.
In a book whose pages are folded in signatures and glued, it is sometimes difficult to tell by looking that the pages are not sewn. Often there are saw cuts across the backs of the signatures that look as if they might be holes for thread.
You can tell the difference by looking at the middle of a signature; in a sewn book, the thread is visible, as in the example shown above. In the glued book on the right, glue has crept in through the saw cuts and stuck the back edges of the pages together.
You should note that both books shown here are open flat. In other words, it's possible to produce a well-bound book using glue instead of sewing.
Copyright © 2008 Allen Watson III