A printing assembly comprises a medium support surface, a guide assembly and a carriage support structure for moveably supporting a print head carriage on the guide assembly. The guide assembly is arranged to move the print head carriage in a carriage plane, which carriage plane is parallel to the medium support surface. The guide assembly comprises a guide beam; and a guide rail arranged on the guide beam. The guide rail and the guide beam each extend in a scanning direction. The printer carriage support structure comprises a guide frame arranged on the guide rail and the guide frame is moveable in the scanning direction and extends in the scanning direction between a first support position and a second support position. The guide frame is supported on the guide rail at said first support position and at said second support position. A carriage frame is moveably supported on the guide rail through the guide frame. The carriage frame is coupled to the guide frame such that the carriage frame is moveable relative to the guide frame in the carriage plane.