edit: Found out why it was doing it. It would seem I forgot to set the normals on the parts correctly (*facepalm*). Also I'm managed to fix the missed face issue as well , now I just to test the part in KSP and I'm happy Hay guys, I've finally got a part made and animated in blender, I import the .blend file into unity and the model displays perfectly in the assets area and in the scene window, but when I goto edit the animation information in on the model, the preview window shows that half of my models parts are completely mucked up. Here is a photo for you guys, so u can see my problem: