Yet another diversion from my credenza project! However, it's related somewhat. Anytime I've worked on a sizable project, one issue is where to assemble all of the pieces and parts. So, it was time to build an assembly table! I decided on 1/2" MDF as the material for all components of the torsion box.
Although I didn't take photos at all phases, these will show what I did, I think. After trimming the full sheet to the final dimensions of 93.5 by 47 inches, I placed the bottom sheet of MDF on three 2x4x8' that were very flat. Then, I added shims until the MDF sheet was dead flat.
Internal components are 3" wide. I left the long strips solid and cut 66 pieces to 7.25" in length for the cross pieces. I failed to get a photo of it, but I made a spacing guide with MDF so I didn't have to measure every location. I attached one long side piece and one short end piece to the base, then started adding the rest of the assembly. After all the rest was in place, I added the final edge strips.
After allowing the glue to setup for a couple of hours, I had my neighbor come over to help set the top sheet of MDF in place. I ran a healthy bead of glue along all of the top edges of the internal parts, then we carefully set the top sheet in place so we didn't smear the glue all over the place. Then, we started putting anything that wasn't tied down on top of the MDF to press it in place securely. I let the glue cure for a day, then added legs so I could retrieve my sawhorses.
This photo was taken after trimming, sanding and shooting a couple of coats of shellac. I'll hit it with a couple more coats of shellac, then put it to use.
Incidentally, I had asked in another thread about some adjustable height legs. I might change to those at some point but for now I have the table top at a height of 29.5", which will work fine for most items I plan to build. It's also just right to sit in a chair to work on smaller items.