Can you illuminate on why this particular grid patter was chosen?
Certainly. There is a lot that went into the decision; but, ultimately, "chosen" is an apt term to apply.
I started with the horizontal and vertical beams seen in the earlier pics. Two problems began to evolve as I moved forward with this idea. One, the placement of the windows began to dictate where the structural members could be placed such that it seemed it would result in a weak design. That nagged at me but not as much as what ended up happening on the leading edge of the dorsal neck. Carrying that design to conclusion would have resulted in more than half the structural load sitting on a single spar in the front. And it would have called for a lot of really odd sized and shaped panels for the skins. So, I pitched that idea, griped, reimported my mesh and started
from the base form again.
From here, I decided the spars should be on the diagonal with some horizontal and vertical members. But, in the process, I also moved
the placement of FJ's windows. He had them almost literally sitting on the floors. I moved them to mid deck level. Did a structural reinforcement with a mid deck horizontal spar and then scratched my head as to how I would handle the forward section. Everhart presented the answer there. So, the design ends up being an interpretation of Everhart. It's not without its problems; but, it's far superior to what I started off with.
I thinks thats a great explanation of what I see.
It's a common misconception that in space there is no gravity and that thus gravity isn't a factor which is far from the truth.
Is it me or does the cage concept for the dorsal section just seem structurally weak? I'm imagining torsional stress between the Primary hull and the Secondary hull and can't break the perception that the cage is going to be far too flexible considering the masses at either end of the neck...especially the entire secondary hull acting against those thin piles.
I thought there should have been 3 very large single section stiffners at the top and bottom of the neck as well as one in the middle for rigidity. I figure those sections would be at least 3 times the thickness of the current sections.
Then to actually control the torsional stress 2 direct vertical sections Running from the front of the base of the neck directly to the Saucer and the other running from the Back of the Crown of the Neck down to the middle of the neck base meeting the Secondary hull.
Since the problem with the neck is the awkward angle and running structural supports, I feel not even that is enough and that a one more stiffener is necessary to run from the middle stiffener section down in the back and another in the front from the middle stiffener section up...
That should remove a lot of play if the Primary and Secondary hull decide to go in two different directions.
Even then I think the Dorsal also needs to be buried in the (so to speak) in the Secondary hull....but I'm no Engineer...just a drafter.