Problem with mesh normals when exporting to OBJ

Hi!
I recently just got back into Blender and I’ve come across a problem concerning the normals. I’ve been modeling a low poly game model in both Wings3D and Blender, and I’ve been getting inverted normals. In blender I don’t see any problems until I hit the show uv button. In the picture below you can see that on the chest and right arm region the normals arenot showing because they are inverted.
http://ee.1asphost.com/jinho326/Question.jpg
This is giving me headaches, especially when I export the model in OBJ format. When I import the OBJ file, I get invisible polygons because theyre inverted. Now my question is, how would I get all the normals to face outwards so that there aren’t any of these issues when I export to OBJ format? Thanks for all the help in advance!

Cheers[/img]

Ctrl-n in editmode with everything selected?

still doesnt fix it all…

Then, in Edit mode, select all the inverted faces and W, Flip Normals.

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I’d go for, in editmode, a-key until nothing is selected. Then make sure you’re in vertex or edge select mode and space -> select-> Non-Manifold to see if there are “inner faces”.

First of all I really appreciate the quick help! But I’m a bit confused as to what exactly this does. I see that some parts of the mesh are selected, but these include parts whose normals are fine…

It means it has selected Non-Manifold parts of the mesh. Quick google of non-manifold Short explanation: A non-manifold is defined when one edge is shared from more than two faces.

That can produce problems as Blender can’t determine what is outside and what is inside, hence the bad normals. What Fligh suggested doesn’t correct the problem as is, but it does deal with the issue of having bad normals.

Non-manifold mesh. Ctrl N works weird if you have them. Maybe those planes sticking out of his head. If they are joined to the mesh, then you have edges with more than two faces attached. Ctrl N would then work weirdly… Basically, Blender can’t figure out which way to point the normals, so they go this way, then the other way if you pressed Ctrl N again…

I see now…I’m trying to apply hair on my character using the card style, which explains why Blender is getting confused. Is it possible to use “card” style hair in blender? Thanks so much!

In the edit mode, you could select the planes, P key to separate and choose “selected” from the popup option. Then you could join them again by tabbing back to the object mode, selecting the separated card hair mesh and the original mesh and press J. As long as the card hair are not attached to the head (doesn’t share a common edge with the head) Ctrl N should work fine.