You can try to create a loft between closed contours instead of just splines.
You can also activate Caps and Roundings in the Loft object, but not sure that is what you are trying to achieve.
I know there is a 'shell' modifier in VIZ/3ds max that generates a thick object from a flat one
😉
--- stefan boeykens --- bim-expert-architect-engineer-musician ---
Archicad28/Revit2024/Rhino8/Solibri/Zoom
MBP2023:14"M2MAX/Sequoia+Win11
Archicad-user since 1998
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