Options for Binding
The stitching of signatures being performed in the photo yields a book text block. Once the text block has been hung on binder’s boards (the case of a case-bound book) or glued to a paper cover, the resulting book will have a spine. If the book is very short, perhaps a printed title will be too large to fit on the spine and still be readable, but for books of 80, 100, or more pages, this would not be an issue. Having a spine adds to the aesthetics of a print book and provides room for the book title, but some books (and magazines) are still too short to be perfect bound or case bound. Therefore, these books are saddle stitched.
With saddle stitching, the press signatures are nested into one another. That is, instead of being stacked next to one another, each is slipped into the center of the prior one, and then metal stitches are inserted mechanically through the pages (at the fold, or where the spine would be if this were a perfect-bound book) and then crimped shut in the center of the folded book. If you open such a book on the table, it will lie completely flat. However, it will not have a spine on which to print the book’s title.
Length of Saddle-Stitched Books
The length of a print book you can saddle stitch will depend on the thickness of the paper. Thinking back to my time as an advisor to a local congressional publisher, I remember their main weekly magazine started to get unwieldly for saddle stitching when it exceeded about 88 pages plus cover. At 96 pages it was somewhat “bloated” at the fold (the magazine didn’t lie completely flat when closed). When the magazines exceeded 96 pages, the center page spreads started to come out of the saddle stitches.