Exported mesh isn't closed

Rhino Rhino for Windows
1

I’ll get right to it. I am trying to analyse a hull form for a ship and to do this i have found a python library called numpy-stl which is capable of analysing functions on a mesh. For those suggesting i use grasshopper, i don’t want to as i need to use some type of goal seek function or binary search.

However, the python library keeps returning a warning that the mesh in the stl file is not closed. The volume and centroid calculations match those of rhino, but i am worried that later on this issue will start causing issues. How do I ensure the mesh is actually closed. I am fairly certain the solid is a closed polysurface. See some screenshots below.

naked_edge
naked_edge776×528 45.1 KB

error

The first image is to try and show that the polysurface has no naked edges and the second image is the warning numpy-stl library gives.

Hopefully someone can help me out here. Any other suggestions for other libraries or methods are also welcome.

2

If you create an .stl of your model directly in Rhino then re-import it, is it closed? Does Check say it’s a good mesh?

3

Moved to Rhino for Windows category.

4

Hello - are you handing the py script a mesh object, or the polysurface and python getting the meshes from the faces?

-Pascal

5

If nothing else works, maybe Netfabb can fix your mesh.

6

When I reimport it, I just get the mesh itself, so all the triangles. Not sure how I make a surface out of it again but it all seems so be in one piece. How do i check if the mesh is good?

7

I am handing the python script a mesh object. I exported it as a binary stl file so it should be opening a mesh. The py code importing it is …

ship_mesh = mesh.Mesh.from_file('ship_mesh.stl')
8

Hello - run ShowEdges on the mesh - look for any nakeds.

-Pascal