stacking {HEAD ~ the plurality} of {TAIL ~ base sheets} together with their interior edges aligned with each other, the aligned edges defining and being exposed on the walls of a cavity 
stacking { HEAD ~ the plurality } of { TAIL ~ base sheets } together with their interior edges aligned with each other , the aligned edges defining and being exposed on the walls of a cavity
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH