A cutting assembly of the type usable for severing a sheet into discrete elements includes an elongate track member having an elongate slot therein. A cutter slide is moveable in the slot and includes downwardly extending projections for both immobilizing and tensioning the sheet locally prior to, and during the severing operation. A method of forming the track, other articles having a segmented upper wall, by injection molding side sections and upper wall segments at an angle relative to the position they assume in the completed article, and thereafter rotating the side sections and upper wall segments about flexible, injection molded hinge sections to complete the formation of the article.