FilltEdge command gets a broken corner(surface) in the intersection

In case 1

  1. When I boolean 3 box united and try to fillet the the 3 intersected edges together, the very corner of the meeting area will be broken.
  2. As vid shows above, this is only happens when I boolean(union) 3 box into one.

Hi, I am trying to understand the reason and the remedy of this problem.
Is there any simple way to put the exploded surface back to the smooth one as in the case 2?

The file is here:
实体编辑.3dm (758.3 KB)

Hi -

The reason is that fillets on edges will stop at edges.
If you run MergeAllCoplanarFaces on the polysurface, the internal edges will be removed and the edge fillet will continue as you are expecting.

1 Like

Thanks, you are right! After boolean the planes are not gone, so I need to do one more step to merge the planes again.