How many layers of CF cloth are there on each side? It doesn't look like more than 2. Very creative and innovative solution . I'm going to try this on a smaller plane with some 1/8" nomex core I have. I built composite landing gear a couple years ago with 1/8" nomex and CF. Very light and extremely stiff. I've worked in composites professionally for 3.5 years, building models with it for 12 years; way back before gassers went main stream with composites
ps: that hybrid stuff is nice but beware that you aren't getting dyed nylon instead of dyed Kevlar (aramid). The nylon hybrid's color fades less in sunlight but also sands like cr@p (worse than the kevlar).
Just for fun (and school credit), I built a coffee table out of 3/4" nomex honeycomb, CF layed up on glass and cleared, soft maple legs and edges. Whole table weighs 9 lbs.