How to "Merge" a Mesh So I have a mesh I downloaded, but it intersects itself. I would like it to be one large single shell instead of having various intersection areas. Like the edges would go through faces. The model isn't multiple objects but one large intersecting shape. Is there a way to make it so it becomes one large shell? 3D Builder, a program which comes with windows, has an option called Merge, but it does a really messy job with it and so I would like something like that in blender.
You basically want to separate each shell into its own object, and then boolean all the objects together.

To do this quickly:


Select everything in Edit Mode
P > Separate by Loose Parts
Enable the Bool Tool add-on (included with blender by default)
Select all the objects in Object Mode
Click the Auto Boolean > Union button in the Bool Tool panel:




You may want to triangulate the mesh in edit mode (Ctrl-T) afterward to make more sense of it.