In today’s world we are finding that more and more we utilise CAD geometry from a software packages that is not native to the one you are using. Autodesk has noticed this and given Autodesk Inventor users a plethora of tools to be able to incorporate foreign CAD models into your native environment.
From being able to directly import CAD geometry from most other CAD software and break the link to being able to externally xref or AnyCAD the geometry where you still have a link to the original model as well as be able to link metadata such as Part Number and Description to name a few.
When incorporating these models from external sources you might want to section to get an idea of what the internals look like.
A strange phenomenon occurred with a model that I was working on. Only a few of the parts would section. My first thoughts were that the import had not taken place correctly. So I started to check if there were any errors. Inventor has a fantastic check errors and repair environment. It can take a while if it is a large assembly but it is worth it in the end. You do not want to be working with geometry that has holes in it, or a surface normal is reversed or maybe a surface edge is slightly twisted. It does not make for good downstream modelling.
After checking that all the geometry was healthy it still would not section. The next thing to look at is in your part document settings. On your modelling tab you need to make sure that the part participates in assembly and drawing sections.
This seemed to do the trick and I was happily able to continue with my work.