Mesh seems to warp with smoothing groups, even after mark sharp

After exporting from blender with smooth faces on and my sharp edges marked, the flat area gets populated with triangles and becomes warped. Ive tried just about everything i can think of, but it always looks the same.

Above Image:
Same model but the left was exported with no smoothing groups and the right was exported with smooth faces. Ive also tried smooth edges, but it gives the same issue.

Above Image:
In blender the one on the left shows the model in edit mode with the area populated by normal faces, on the right is the same model in object mode showing the area with no geometry.

When in UE4, both versions of the model show the area populated by triangles but only the one with smoothing has the warp looking triangles. Any idea what is causing the warped look and how to fix it?

Thanks in advance!

similar problem here. I did a heap of tests with exporting from blender.
for the test if used a simple cylinder with an edge loop half way up then contracted the loop inwards.

  • Smoothing set to normal(Off)
  • Edge
  • Face
  • Recomputed normals
  • edge split
  • triangulate
  • lightmap channel checked
  • lightmap resolution (64,128,512,1024)

nothing seems to fix the problem other than the bevel modifier which creates way too many polygons to fix the problem when you can just export with no smoothing groups.

Normal Smoothing (Aka off,well UE4 says no smoothing groups) -

Edge smoothing (Same result with all tests above) -

So do we really need smoothing groups?

Just found this thread, Here Followed the comment by Awesome_Junior_Miss near the bottom and it helped the issue still a little funny looking when compared to no smoothing groups bu by no way bad. Seems like you have to mark the corners (Sharp turns) with the command marksharp.

Try grabing the edge loop near the bad shadows (Alt + right click on edge), hit ctrl + E and click mark as sharp then export with edge smoothing. See if that helps.