Hello I have done it using Grasshopper and a script I wrote, you will need Millepede plugin for GH (don’t care of the message)
If you want to use the script beware it is a bit long, so Disable solver, put the offset you want 0.9 mm in “real unit”, load your mesh and enable the solver. I made an hole in order to have a unique mesh visible with clipping plane. Instead you must take care of direction (I think).
Anello 500_interior.3dm (1.2 MB) I