Pro tip: my bench top router table build went sideways in one afternoon and it was my own fault
Everyone says build the router table top from MDF first, but I went straight to a 3/4 inch Baltic birch slab I got from a guy in Tacoma for $38. I glued up the torsion box on a Saturday, checked it with a straightedge, and it looked dead flat. Sunday morning I set my router in the plate and the whole thing rocked on two corners, about 1/16 inch of twist I never caught because I only checked one direction. I clamped it down to my bench for two days and it still sprung back. Turns out my garage floor slopes toward the door and my bench sits right on that slope, so my flat reference was never flat to begin with. Anyone else build a whole top before checking their bench with a level first?