Abstract: A machining center having a draw bar extending through a spindle with coolant positioned inside the draw bar for cooling a tool comprises a piston rod movable between an operating position and an extended position, a drive post rotatable about an axis of rotation, operatively connected to the draw bar, a coolant union comprising a non-rotatable portion and rotatable portion, wherein the drive post is attached to the rotatable portion such that the rotatable portion is rotatable with the drive post about the axis of rotation, and a bridge, wherein the drive post extends through the bridge to attach to the coolant union and the bridge permits rotation of the drive post but resists dislocation of the drive post from the axis of rotation. Movement of the piston rod from the operating position to the extended position moves the drive post and coolant union to an extended position.