an imprinter apparatus which utilizes a print roller traveling within a carraige over a base plate is provided with a rolling assembly which engages channels in the base plate to minimize play between the carriage and the base plate . the rolling assembly includes a first set of rollers which are laterally constrained within the carriage , a second set of rollers which are free to move laterally , and means for retaining the rollers in the channels . the imprinter apparatus is further provided with means for selectively lifting and lowering the print roller at the end and beginning of the print stroke . the lifting and lowering means includes inclined planar regions on a plastic molded print roller axle and cam means for laterally sliding the location of support of the axle along the inclined planar surface to selectively lift and lower the print roller .