Book trimming

Book trimming is the stage of the book production process in which the page edges of a book are trimmed so that all pages will stack with perfect edge alignment within the finished book jacket.

The step before book trimming is the binding of the folded printing sheets. Trimming is performed either with a hydraulic book trimmer that is able to cut a whole book in one or two passes or, until the invention of hydraulic book trimmers, with a cutting press (or lying press) and plough.