I was able to finish the remaining torsion box structural parts last weekend. It took about 4 and a half hous to make the horizontal gantry pieces, and 5 hours or so to make those other pieces with my current diy cnc (lots of time used to set-up, sanding etc.)
Simple method for quickly cutting pieces of exactly same length
Some parts ready for assembly.
Lower support beam nearly assembled
Some Y and Z axis parts.
Testing the gantry assembly.