A colour ink printing system includes a plurality of print head cartridges, each extending across and spaced apart along a direction of print media propagation; a print head chassis for supporting the plurality of print head cartridges, the print head chassis actuable between a printing position, a transition position, and a maintenance position; a maintenance chassis for supporting a plurality of maintenance cradles, the maintenance chassis actuable between a storage position and an operational position; and a plurality of supporting arms respectively extending upwards from each corner of the print head chassis. Each of the plurality of print head cartridges is held stationary with respect to a platen on which print media is propagated to effect printing on the print media. Each of the plurality of print head cartridges is a monochrome print head cartridge ejecting a fluid different to the remaining plurality of print head cartridges.