3d scanned mesh

Hi everybody,
I have a 3d scanned mesh of a ring, I wanted edit the file to print it again.
The problem is that when I offset the object the mesh created presents “449 pair of faces that self-intersect” and even if is a “good mesh” I can’t proceed with boolean operations.
Thanks a lot,
I’m a newbie on Rhino.

From the sounds of it, you need to weld the mesh before offsetting. Perhaps you can post the file for somebody to take a look at?

Thanks Wim,
Here is the object.

Hi Luca - the mesh offsetter is not intelligent - it cannot tell when an offset creates a self intersection and I can see in this case how that might easily happen depending upon the offset distance.

This is an image of an offset of a section through the mesh - you can see where the self intersections will occur:

The solution involves a bit of work I would say - what is the desired thickness?


Hi Pascal,
Thank you very much for your answer.
I need a thickness of 0.9 mm, what do you suggest to do?

Can you do the ‘offsetting’ in a 3D program? Start with a single manifold solid mesh, and define your perimeters and infill in a slicer program. perhaps try Meshmixer, I think it is a little more intelligent in terms of avoiding self intersecting meshes.

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

Thank you very much, Laurent!
You gave me a very useful advice, Grasshopper seems a good start for my work.
I may you contact for more information.
Thanks to everybody.

You are welcome
I also tested mesh mixer and it works well with your file