>I was also surprised to see that the inner aluminum ceiling skin is not
>riveted to the first rib down from the top (running front to back), on
>which the exterior skin seam lays. It IS riveted from the outside. Is this
>an intentional engineering technique to allow more flexibility?
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When I had some of my interior panels off on my '56 Bubble I noted
similar construction. It appears some of the horizontal struts? or
ribbing as you call them appear to be in place to simply add some
strength to the panel it is connected to. Some attached to the exterior
panels while others were attached only to the interior panels. I
noted that the ends of these horizonatal ribs were not connected to any
other structural members.
Roy Lashway