CNC Router V1.0 (For Cutting Multiple Materials)

[routercnc]

My Z axis plate is 147mm wide and the Z rail centres are only 115mm apart. I did this to maximise Y travel and placed my Y axis bearings pretty much back-to-back.

This works fine for me, but it can give you more stability and less likely to rack if the Y bearings are spread further apart, but you are trading Y travel. If you do spread the Y axis bearings out further, closer to Lee's figure, then I don't think you need to follow suit with the Z rails and can keep them fairly compact.