What is a non-manifold mesh and how to fix it - Sinestesia
modeling - Fixing rips on meshes - Blender Stack Exchange
11. Repairing Meshes — MCell and CellBlender Tutorials
How to detect and repair errors in mesh? - Blender Stack Exchange
How to fix mesh errors in Blender - YouTube
Blender 2.8 repair mesh - Blender Stack Exchange
topology - Best way to fix this mesh? - Blender Stack Exchange
Blender for 3D Printing - In-depth guide to fixing mesh issues plus Blender usage tips. - YouTube
Mesh repair not working on my file, i converted the file to a stl using blender. I am also unsure how to give it a positive volume https://3dwarehouse.sketchup.com/model/7bd16dcb62536444bf518bc773843ca7/Lincoln-Continental-Mark-IV : r/Fusion360