Autodesk Fusion 360 / threads not printing

So I made this beautiful tray with threads in them using the thread tool.
Exporting .STL out of Fusion 360. After importing into Cura model looks great - but threads are gone…

Any leads / idea why this might be happening ?

Sounds like you need a third opinion… If you are using Windows 10, Microsoft’s 3D Builder is available from the store. It has a decent viewer and it is also a useful tool for repairing .stl files. If you are not using Windows 10, there are other free .stl viewers available. Even Tinkercad is useful for a quick look.

If the threads are there in the .stl file, then exploring why CuraLE doesn’t see them is next.

The threads are default just visual, not actually part of model. This post can explain it better and how to get them as actual threads.

search for and download “Cool Orange” for Autodesk. It is a thread modeler that works pretty good. Autodesk products like Fusion or Inventor do not actually model the threads. What you see on the screen is only a representation. Cool Orange will create the 3D model of the specific thread so that it can be printed.