single layer of packages is fed to the cutter 14 the metal detector includes as shown in fig2 amp 4 a conveyor belt 24 a detecting head 25 and a conveyor retracting actuator 26 for dumping the material on a section of the belt 24 when metal is present therein the belt 24 extends around a roller not shown under the end of surface 22 under the detecting head 25 and around rollers 27 29 and 30 the roller 27 is slideably mounted and is spring biased into the position shown in fig3 the roller 29 is also slideably mounted and is moved by the actuator 26 between the positions shown in fig3 and 4 the roller 30 is rigidly mounted when no metal is present on the conveyor the actuator 26 is extended and the roller 27 is held by biasing springs over the end of the conveyor belt that feeds the cutter 14 so that the packages feed continuously to the cutter should a piece of metal be present on the belt 24 it activates the detecting head as it passes thereunder which in turn energizes the actuator 26 as the actuator retracts the roller 29 moves to the left as viewed in figs 3 and 4 tensioning the belt and drawing the roller 27 to the left so that the contents of the conveyor drop into a bin 31 the detecting.