Even with 63% decimation there are 258232 faces in that mesh (not 26563 as you mentioned). And even if you convert that to a shell all those 387348 edges will still be there and TechDraw will try to include them in the drawing. At each edge end there will be a point (to select for dimensioning, ...)...

Not sure how but this works. Sweep Transition is set to Transformed for this to work.

I am not sure about those tolerance values, how they are calculated, stored, used...
Could you extract a simple version of that wing that creates those edges and still exhibits the error?

I get "Illegal storage access" under windows. Also using "Create surface from picked boundary edges" creates weird result and again causes "illegal storage" after some clicking around. But Check Geometry gives errors on all elements - selfintersecting and too small edge...

DaveNadler wrote: ↑Wed Jan 13, 2021 3:32 am I did search but did not find a solution.

Have you tried this https://forum.freecadweb.org/viewtopic. ... 20#p298347

Or this post https://forum.freecadweb.org/viewtopic. ... 88#p332523
Which Graphviz version are you trying? Does it happen with every file?

Thanks. What was the scan made with? I am planning to use photogrammetry from a video with Meshroom.

thomas-neemann wrote: ↑Wed Jan 13, 2021 7:29 am the parts are from grabcad.

Any link, name, user, ...?

It was mainly wrong mappings. Some sketches were mapped to faces of generated geometry (pad, pocket, fillet). This was the main reason for the cyclic dependency. I remapped those to basic planes (XY_plane, ...) with corresponding offsets where needed. A sketch used inside the body was actually outsi...

Fillet follows tangent edges. So it can not fillet just the vertical edge. And the arc from the previous fillet ends tangent to the top surface which causes the fillet to fail. If you fillet first the vertical edges and then the top perimeter then it will succeed.

I know here is not the place but since there is no separate thread about 4487 ... What is the actual issue for this bug? The wrong geometry created by the fillets? OCC crashing when supplied with wrong geometry? FreeCAD crashing when OCC crashes? If I remember OCC crashing FreeCAD was treated on a c...