Printer and stacker and methods of printing and stacking labels

Disclosed are a printer and a stacker and methods. The printer prints selectively on one or both sides of a printable web and sheets or labels are cut from the web and stacked in the stacker. The printer has an unwind mechanism that accepts and holds web rolls of different widths in center-justified relationship with respect to a print head. The printer has a spindle for mounting an ink ribbon core with a detent for center-justifying the ink-ribbon with respect to the print head.