Tony LEE
International Grey Nomad
This build won't be directly applicable to yours but it does demonstrate that a fully-frameless construction using sandwich panel works.
https://picasaweb.google.com/114611728110254134379/OKABoxConstruction#
All DIY design and construction from the chassis up - stuck together with one-pack polyurathane adhesive with additional fibreglassing internally and aluminium angle externally.
Current trip involves about 15,000km with about 5000km across the Simpson Desert, Gunbarrel Highway, Canning Stock Route and the Gibb River Road with no sign of any failure of any joints
https://picasaweb.google.com/114611728110254134379/OKABoxConstruction#
All DIY design and construction from the chassis up - stuck together with one-pack polyurathane adhesive with additional fibreglassing internally and aluminium angle externally.
Current trip involves about 15,000km with about 5000km across the Simpson Desert, Gunbarrel Highway, Canning Stock Route and the Gibb River Road with no sign of any failure of any joints