Fundamentally many of our users (and Winston) work in imperial, we wanted each piece of the table to be 4" wide as it’s a great reference when setting up and working on projects.We also have to allow for a small gap each side of each table extrusion and make sure we gave a full 48" or 24" of travel with a little bit of extra for side operations. (Note travel is greater than the machine bed).
All in that spacing made the above possible.
We will be conscious when rolling out accessories to make them compatible with both current and new models, but most vices and accessories will accommodate the 4.04 without difficulty.