the thinnest web sheet to be conditioned also there is again a biasing mechanism that will force the blade 68 b against the web once the web has displaced the blade away from the interior wall a distance greater than x the mechanism for supporting the blade and for applying the biasing force is not depicted also the end strips 58 b fig1 cut by slitting blade 71 b is not depicted in fig1 a fig1 b shows the cross section along line 14 b 14 b of fig1 where the associated web edge 56 b first contacts angled surface 74 but has not yet begun to be bent by the surface as the web 56 progresses past the bending blade as shown in fig1 c the angled surface 74 commences to deflect the web edge 56 b down into the groove 72 b fig1 d shows a cross section of 14 d 14 d of fig1 showing the angled surface 74 as it continues to fold the web edge 56 b around the relatively sharp corner c formed by the upper surface of roller 60 and the inner wall 73 b of groove 72 b as the folding progresses the web 56 b has been driven past the angled surface 74 and has engaged the flat surface 76 fig1 of the bending blade 68 b with this surface forcing the web flat against the inner wall 73 b of the groove the previously noted biasing mechanism not depicted forces the blade against the web edge 56 b so that the web is tightly folded around corner c with this action tending to create a tear or fracture 44 in the edge in the same manner as previously.