Quote Originally Posted by jcb121 View Post
yes, I have a sliding Bed design so I only need one, not only that, but the entire cnc will be more rigid and make things better,
A sliding bed does not mean you only need one ballscrew to drive it. When the cutter is at either limit of the Y-axis travel and cutting parallel to the X-axis the cutting force will create a significant torque on the bed causing it to deflect. How much it deflects depends on the spacing of the bearings supporting the bed, the distance between them and of course the cutting force. Two ballscrews completely eliminates this problem. It's like trying to go round a corner fast in a Reliant Robin...it does work but not as well.