I wanted a metal internal frame to ensure it will support manipulations (transport and convention exhibition) and allowing me to exhibit it under different ways. The display stand points will be:
- underside, with a table leg (as I did with my 37" Galactica)
- Or by the sides, with square tube being inserted in the lateral trenches

So the internal frame is a cross, made from aluminum square tubes of 2 cm width, riveted together with metal brackets, and a metal plate. The underside is maintained by riveting the table leg.
The materials are so hard I broke 2 hand riveters in this operation!
So it will be very strong :)

The center of the rib is cut in order to the cross go through. The rib is then glued and screwed on a first triangle side.

The center of the belly dome is hollow to allow the display stand/table leg to go through.

The edges are dig so that the cross arms of the cross settled well.