How to fix failed edge fillet?

Hi everybody,

What’s a good method and/or strategy to remedy a situation like this, where a fillet failed?

I usually explode the model into its subsurfaces, extend relevant surface edges, and trim everything to remedy failed fillets.

However, this is especially tricky here, because the round fillet surface extends parallel to the connected surface below and overlaps it when extended linearly, or rolls into itself not intersecting the lower surface when extended smoothly. Both extension methods yield surfaces, which make trimming the lower surface impossible.

I’ve managed to fix such cases before, but usually with lots of trial and error and constructing geometry aids.

Does somebody know a simpler approach?

Extract and Untrim the two surfaces from FilletEdge, as you said.
But you also need a FilletSrf between surf 1 and surf 2.
You may need to obtain the base surface (untrimmed) from surf 2 to be able to draw this fillet.
Finally Trim and adjust all the concerned surfaces, flat ones included.



Explode the polysurface

Do ShrinkTrimmedSrfToEdge for A and B.
Untrim edge Ea and Eb.
Extend edge Ea and Eb.
You will need to have some extra material on surface C, try with solid control points on that surface alone.
Select everything and trim.


I would try this approach

attached the file with all steps explained.

Fillet_LZ.3dm (531.0 KB)

Edit: Steve told me that in the old file annotation were missing… i uploaded the file again.


Fillet_SPB.3dm (393.2 KB)


Thanks for all the great suggestions everybody! Problem solved.