Abstract: A vertical rack-type spline-forming machine based on a novel slide base arrangement comprising a pair of vertical slide bases structurally joined by a symmetrically arranged set of tie bars. The structurally-joined vertical slide bases can be rested in an upright position on a non-structural space frame which provides improved access and lift capabilities to the vertical machine. The machine also includes a novel drive system using independent electric motors, one motor associated with each vertical slide base to drive the rack on that base through a roller screw shaft mechanism. The racks are further electronically synchronized through position signals communicated between the motor drives, and the rack home positions are calibrated with electronic "datums" programmed into the motor drives and capable of being re-calibrated in programmable fashion if one of the racks loses synchronicity.