Separate parts of an imported mesh for repair?

[Anonymous]

Hello,

I'm very new to Fusion 360, and very rust on CAD in general. I'm trying to import this mesh of a molecular structure, but would like to keep the atom spheres each as separate entities while doing a mesh repair on the underlying molecular structure. It looks to me like Fusion is recognizing the spheres as not being connected to the body, and when I import the .obj into another rendering program the spheres are one body, while the sticks are another. 

How can I parse out individual spheres as separate bodies, so I can color them separately, while keeping the sticks as one body so I can repair the mesh? Currently it looks like it's all one body.

This is imported into Adobe Substance Stager. Spheres are all part of one grouping but still separate from sticks.

[TheCADWhisperer]

I’ll wager that there are no spheres.

Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply?

[TrippyLighting]

Can you share the original .obj file and explain what repair is needed?

[Anonymous]

Here you go! Why would there not be spheres if another program can recognize them?

[Anonymous]

See my reply to the other comment for files. The sticks are all separate and need to be repaired into one continuous mesh. I have no issue with this when I import the structure without the spheres.

How it imports the .obj, as all these separate sticks with defined ends:

How it repairs the mesh using Repair Type: Rebuild, Rebuild Type: Accurate

When the spheres are there it tries to repair the same way, making the spheres continuous with the stick mesh.

[TrippyLighting]

When you work in CAD software and create geometry, that geometry has topology (in a mathematical sense).

The same is true when you create geometry as a quad-mesh with a polygon/Sub-De modeler (Maya, 3DS MAc, Blender, etc).

Once the geometry is exported as a triangulated mesh as in this case, data is lost as a triangulated mesh has a finite resolution and also no topology. Your brain recognizes the shapes as cylinders or spheres, but the computer does not.

[TrippyLighting · Accepted solution]

Hopefully, this screen recording explains the process:

[Anonymous]

Thank you so much for taking the time to make this video! This is extremely helpful, and exactly what I was looking for!! I also realized that as long as I have the spheres rendered over the intersections of the sticks, then they'll be hidden inside the spheres, so no need for the tedious stick capping 🙂