Abstract: A signature booklet making apparatus for an electrophotographic printing machine, the booklet making machine having a trimmer blade blower and high capacity waste bin. Selectively operable air ducts are provided to distribute an airflow either across the trim blade to remove trim scraps or through a bypass duct to efficiently fill the waste bin with scrap. A valving mechanism responsive to the operation of the trimmer directs the airflow to the correct duct. By selectively causing the air to flow across the trim blade the chance of forcing thin booklets into the waste chute thereby causing jams is minimized.