Question Blender files issue with Object showing holes

Hi,

I dont know why but everytime i import something from Blender i just pray that everything will work out OK, and mostly it doesnt.

I've started creating some assets on Blender, they look great on Blender but they always have issues when exporting to Unity, i fixed my previous problems with missing textures and vertex colors after searching online for quite a bit.

The problem i'm having now is holes that appear in my Object, again, just in Unity.

This is how it looks in Blender:


This is how it looks in Windows 3D Viewer:


This is how it looks in Unity:



What I've tried so far after searching online:

1. In Blender, i've made sure there are really no holes, and all Vertices connect and nothing is broken.
2. in Blender In object mode, I've tried to change or flip Normals
3. In Unity, i've tried to go to Render face and select "Both", on the Material
4. In Unity, I've went to the Object, to the Material Tab, and changed the Normals drop-down to "Calculate", also tried taking the Smoothing angle to 0.

I'm at a loss here, this seems to be a pretty straight-up work, create a cylinder, add some spikes by just pulling vertices up and to the sides with proportional editing, and pushed some parts back, thats really all i did.

Really hope there's a simple way to solve this

Many thanks in advance!

 

Use the "face orientation" overlay in Blender to see which polygons are facing the wrong direction so that you can fix them. Also Check and make sure that you don't have any overlapping faces.

 

@kdgalla so i did that:
couldnt find any that were facing outwards:


and no overlapping faces as far as i can spot, is there any automatic way to find those out?

 

Are you sure? "Face orientation" should make the model turn blue. with red faces being in the wrong direction.

 

I have the same problem now. I even separated the face as an object and it is just becoming empty in Unity
On top is blender, on the bottom is Unity. The same happens when the question was not separated(except that the bottom dot in the question mark was also a hole)

 

Why is it three separate meshes? Are all of the meshes at 0,0,0 in Blender? If not "apply" the transforms, otherwise Unity will move the meshes relative to each other. I'd also combine them into one object in Blender.