I found that there are some issues with the judgment of data regarding the hollowing out of entities.

[nonozone]

Now I need to add an internal thread to the narrower part inside the cylinder, and I want to achieve this by hollowing it out. The diameter at this position is 6.05. The thread specification I want to add is M6.5*0.5, but I found that when adding M6 or even M7, there’s always a prompt saying that no intersecting entity can be generated—unless it's changed to M8. However, after changing it to M8, I realized this is completely not what I wanted.

It seems like during the hollowing process, the minor diameter of the thread specification might be used for matching with entities instead of using the major diameter for cutting/intersecting entities—which should be unreasonable in this case. It should use the major diameter of the thread for cutting/intersecting entities instead.

[TheCADWhisperer]

@nonozone 

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

Do as cosmetic thread without the chamfers, add the chamfers and then change to Modeled thread.

[nonozone]

This method is indeed a way to handle it. However, it is limited to operations on already created entities. If the chamfer of this entity is directly created in the sketch, this method might work. But you can first create a reference entity using a thread and then use an intersection approach.

Although the problem can indeed be solved, I think Fusion's handling logic in this regard does need improvement.

[kacper.suchomski]

The threading process is the process of removing material (of course, in 3D printing it is different, but the algorithms of most CAD programs support the classic workflow).

The threaded holes should be the same diameter as the hole drilled prior to the threading process itself; just as is the case when creating cosmetic threads.