Sketch does not extrude

[Vagulus]

Sketch25 in the IPT (in the ZIP attached because Autodesk Inventor Forum will not upload Autodesk Inventor Parts 🤔) will not extrude.  All I get when I try is

I have tried placing sketch points at each intersection but that didn't help.  All lines are fully constrained and, as far as I can find out all the lines join up but AI2018 is not having a bar of it.

Would someone please take pity on what remains of my hair and tell me why?

Thanks

[johnsonshiue · Accepted solution]

Hi! I believe this has something to do with the small arc tangent to the big arc. Place a point at the exact intersection and use Split command to split the big arc. After that, the profile should work.

Many thanks!

[Vagulus]

Spot on (again) 😁

Thanks johnsonshiue .

BTW: I think that is the first time I have used the 'Split' command.