Apparatus for adjusting and maintaining printhead-to-platen spacing in a printing device, wherein the printing device includes a carriage for holding printhead, the carriage pivotally mounted on and reciprocally shiftable along a guide shaft, and wherein an anti-rotation rail disposed adjacent a hanger in the printing device engages the carriage to determine its position relative to a platen, the apparatus comprising:
- clamp structure connected to the anti-rotation rail and extending through the hanger operable for clamping the anti-rotation rail to the hanger;
- and
- adjuster mechanism rotatably connected to the clamp structure operable for selectively shifting the anti-rotation rail vertically upwardly or downwardly, while the anti-rotation rail is still clamped to the hanger structure to position and maintain the carriage, and correspondingly, the printhead a preselected distance from the platen.