set smooth problem

This maybe a dumb question, but when you make half a model mirror it and then join it- a seam looking mark appears when i press set smooth. can i get rid of this? is it a problem? when i make a mesh in this way the textures seem to be screwed up in game mode.

have you tryed ctrl-n also a picture would help

After you joined the meshes you have to go to edit mode, select all vertices (or at least the vertices where the seam is) and remove doubles.
Than as HecticHermit said recalculate the normals outside via ctrl-n.

Ctrl-N and remove doubles should not be necessary if you use the new Mirror Modifier (Blender 2.4+).

Thanks, I try that.
I think my set smooth problem texture problems are unrelated.

I have blender 2.42 now instead of 2.37 or whatever it was (mm… speedy rendering).

What does recalculate normals actually do? does it set the visible side of the face to outside?

My texture problem seems to be cause by the way i was uv mapping. If I want to texture 2 things (as in both ears of a human or some thing), why when i select both ears then map from window does the texture only appear on the side I mapped it from (as in side view left of the object)?

Or is this what crt-n fixes?

Thanks for your time and help.

Thanks everyone.

Recaluting normals worked after i figure out i forgot to select all of the model. My texture problem is solved and my model is now smooth!!

Why don’t texturing tutorials metion that the normals may turn out wrong?
-don’t need to answer

thanks again everyone.