So I think I’m going to build a 56"x45" LR2 with a work area of 48"x30" and use the 56" for the X Axis, so I can have the machine go front to back, instead of side to side. What I’m looking at for the table, is a 2x4 top frame, 3/4" mdf on top. Was going to cut two strips probably 2", more if needed, for the rails to sit on, but leave them separate from the base top, so I can replace the center top as needed without having to remove the gantry. I have seen some people talking of a torsion box, not exactly sure if that is adding the mdf to bottom side as well. Do I need the mdf on bottom side? If I do, I was going to attach 4x4 posts to the inside of the frame for legs, then probably build a shelf under near the floor for storage and strength. If I need the mdf on bottom, do I cut out for the legs and put on like I plan, or do I put them direct to the bottom of the box using brackets? Any suggestions would be grateful.