Abstract: A tool for removing material from a body about the circumference of an aperture through the body. The tool includes guide structure for fitting into the aperture, the guide structure having a major axis which is maintained in alignment with the longitudinal axis of the aperture when the guide structure is fitted into the aperture; includes a cutting assembly for selectively cutting material from the body about the circumference of the aperture; and includes attachment structure attaching the cutting assembly to the guide structure for arranging the cutting assembly at a specific location relative to the longitudinal of the guide structure.

Abstract: A tool for cutting a slit into the ends of one or more web portions of a membrane wall. A guide bar is secured above the web portions. An arm member is swingably attached to the guide bar. A cutting unit is attached to the distal end of the arm member for engaging and cutting a slit into a web portion of the membrane wall when the arm member is swung between first and second positions.