Abstract: A blade setting tool assembly for clamping a plurality of heat seal and cutting blades within a blade retaining channel of a three blade seal bar is disclosed. The blade setting tool assembly includes a blade positioning block having an upwardly directed blade positioining slot extending along its length to receive the exposed blade edges. A pair of mounting straps fixed to the blade positioning block extend upwardly along opposite sides of the block and include upper ends terminating above the height of the blade seal bar. The strap upper ends are each formed with a slot open to one of the vertical edges thereof to receive opposite end portions of an eccentric roller extending between the upper ends.