guided path of travel of the carriages 17 at an elevation slightly above the cans 20 supported thereon the frame member 25 is rollably supported on the guide rail 15 by a pair of flanged rollers 26 only one of which is shown in the drawing and similarly the frame member 25 39 is rollably supported on the guide rail 16 by a pair of rollers 27 only one of which is shown in the drawing a drive motor 28 is operatively connected to one of the rollers 27 for driving the can replacement carriage assembly 24 along the guide rails 15 16 the drive motor 28 is operatively connected to a signal receiver 29 which is adapted to receive can replacement signals generated by the transmitters 12 associated with the spinning positions 1 of the spinning machine whereby the motor 28 is operative to drive the can replacement carriage assembly 24 to a parked position at the spinning position 1 generating a can replacement signal in order to execute a can replacement operation at the spinning position the can replacement carriage assembly 24 includes a can manipulating mechanism 32 supported for movement along the gantry portion 30 toward and away from the spinning machine along a horizontal guide rail 31 mounted to the gantry portion 30 the guide rail has a generally t shaped cross sectional configuration the manipulating mechanism 32 having four guide rollers 40 41 only two of which are shown in the drawing positioned for rolling engagement with the guide rail 31 to support the manipulating mechanism 32 for.