just rebuilding my router properly. aluminium extrusion in a u shape with 3/4" joining the top for the y axis. i have assembled the x rails on to a steel frame and connected the extrusion to the x axis slides, but if hold on to one of the sides i can move the other side a fem mm by hand, obviously not good! i was going to drive the x axis with just one ballscrew mounted to the bottom of the "u" but should i mount two one to each side of the miiddle of the "u". if i do this , how do i drive both motors. can i just use one driver board or do i need two? help needed before i machine motor mounts and screw supports next week. thanks all