MODULAR PRINTER HAVING NARROW PRINT ZONE

A print bar assembly includes: a mounting frame having a pair of opposite first and second sidewalls extending parallel to a media feed direction, the first sidewall having an upwardly extending first guide slot defined between opposite first bearing surfaces; a print bar carriage slidably received within the mounting frame and an actuation mechanism operatively connected to the print bar carriage for lifting and lowering the print bar carriage relative to the mounting frame. The print bar carriage includes a chassis, a printhead and a pair of first bearings rotatably received in the first guide slot. During sliding movement of the print bar carriage, the pair of first bearings travel within the first guide slot and bear against the first bearing surfaces to constrain rotational movement of the print bar carriage.