Blender import missing faces please help!!

Hello I always have trouble importing Blender files into Unity. I believe I am using the latest version of both. (Unity 3)I have followed along with other similar questions and answers but just none of them seemed to work.

I am making a FPS game in Unity and I have a Blender gun model and when I import it into Unity a bunch of faces are missing and if I rotate to model the face on the other side appears. I don;t know how to fix this as I purchased the model online. I have tried exporting the file to various files I know work with Unity. If anyone could help it would be truly amazing. Please respond!

In games, faces can only be visible on one side. For example, if you have a plane it will look like a large, flat square. But if you look at it from the bottom, it will be invisibe. That’s pretty much what happened to your gun model. It’s because the “invisible” faces on the model have their normals in the wrong direction.

The following instructions assume that you have some experience with blender.
To solve this problem, open up the model in blender. Select the gun mesh and go to edit mode. Select the entire model so it turns orange, then go to the toolbox on the left. Now press Normals > Recalculate. This will recalculate the direction of the normals, and hopefully get them right. But if you have a complex model, the recalculation may not work properly. Then you will need to flip them by hand.
I’ve uploaded a video to youtube of when I modeled a spaceship in blender, and about halfway into the video I got problems with the normals. It’s a timelapse video, but you should still be able to see how I fixed the problem. Don’t get me wrong, I’m not trying to get people to watch my video, I’m posting the link to help you solve the problem. It should help you find how to recalculate the normals, and how to flip them by hand if neccesary.
Anyway, watch it here. Skip to 04:50.
Also, to see the flipped normals in blender, change the shading from solid to texture. This is also shown in the video.
Rememer that texture shading reqires a light in the scene.
Normals can also be displayed through an option in the toolbox that shows up when you press “N”.
Hope it helps!

I know this is an old question but maybe this answer helps someone.
I had this problem and i found the solution myself, on blender select all vertex on edit mode and go to Mesh->Faces->Triangulate faces.
Seems like Unity has some problems with faces that have a lot of vertex.


I’m posting this here, because I had a really hard time figuring out the solution. The obvious answer is normals, right? 9 times out of 10. But if you toggle the visualize normals (bright blue lines) on you quickly realize it’s not that. You can quickly double check it at the tiny unity mesh preview window. Also if your normal is flipped it should still be visible on the flipped side. If it’s not, it’s a material slot problem.

The solution was a bit obscure. Try going to your mesh (unity side) and adding another material “slot” as in Mesh Renderer component → Materials → Size and add one (mine was from 1 to 2). Boom. Missing normals are visible again. That mean your mesh renderer doesn’t have the sufficent AMOUNT of materials in it. I always figured that if there’s a material missing, it’d show it as pink “material missing” color. Apparently if you added normals to an unwrapped mesh in blender and it assigns a new material slot to it. Go to your materials and delete the additional material slot. Voila. All of your mesh uses the same material.


If the Face wasn’t visible from any side and the model definitely has only one material, this might help. If your model has a lot of verts, unity automatically separates it. Search for some meshes ending with “MeshPart0”, while 0 can be any integer.

IF none of the approaches above work, check if the scale is negative. If so just delete the negative signs in scale and adjust your mesh to a correct position. It should be fine now.

Use EDİT Mode —> Select all Vertex with shift at the inspector . USe Mesh -->Separate—> By Materail all is this.