Trouble threading, selected faces deselet and cannot be selected again.

[kraemer.dampfmodellbau]

Hello!

I modeled a Part and threaded it. Then i tweaked some dimensions, the thread got incomplete and I deleted the Thread to generate a new one.

Now it is impossible to put any threads on that part. When you selct the face and choose "thread", the face deselects, the threading menu says "Select faces" but you cannot select any face.

I Deleted the body, no help. The I deleted the entire component and generated it again, still no help.

WTF is going on?

[kraemer.dampfmodellbau]

Oh, I even saved the basic sketch as DXF, opened it, re- generated the Bodys, Still not threading.

Threading on other parts works...

[jeff_strater · Accepted solution]

which face are you trying to thread?  There are a lot of faces in this model.  Do you have a version of this model where the thread was applied, before you started to make changes?

If you cannot select a face for threading, the most likely cause is that it is not a cylindrical face, but instead is a conical face.  You cannot apply a thread on a conical face in Fusion.

Looking at your sketch, I can see small angles between lines.  That would generate conical faces using the Revolve feature:

[jeff_strater]

I added a few horizontal constraints to your sketch, and in this version, more faces can be selected for the thread feature.  I don't think that this version is usable as it is, but I would encourage you to fully constrain your sketch, and be purposeful about which faces need to be vertical or horizontal.  Add dimensions, including angle dimensions, where appropriate, etc