Bookbinding machine operator performs a series of tasks in binding books with machines. He/she sews together signatures to form book bodies with a sewing machine, compresses sewn-together signatures of book bodies to uniform thickness with a smashing machine, trims books to size with a powered cutting machine, inserts each book into a machine which rounds backs and forms grooves at the back edge in which covers are hinged, stacks and aligns books, glues the superlining and back-lining on each book, glues the cover to the end sheets, and places books in a press to dry.