The invention is a method of manufacturing lightweight fibrous casings constructed of abaca paper substrates suitably wet-strengthened using viscose, or viscose and resin, and subsequently viscosed a second time, and the casings made by this method. The method of this invention employs an arrangement of a die and related apparatus for the single-sided viscosing of light weight paper substrates at increased machine speeds. The die arrangement of this invention provides superior impregnation of viscose during the casing manufacturing stage, ensures smooth surfaces of both the inner and outer casing surfaces and renders the need for double-sided viscosing unnecessary, or undesirable. This new arrangement of viscose die minimizes drag upon impregnating the paper matrix with viscose and during the subsequent crucial period before coagulation of the viscose and its regeneration into cellulose has been completed; so as to permit the casing to be stretched but not irreversibly.