problem using blender Thread

I have been using blender to successfully make models for HL2 DM and i just made one and when i opened the model in the model viewer it was seeing through the prop so you could see the other side and if youturn the see through effect turns, its hard to explain but what could be the problem?<!--Session data-->

i dont understand completely what you mean but are all your faces fliped the right way (flipping normals)
is it like when you view your model you see the inside like a cave (concave)

Best way is to select all faces and hit CTRL+N to flip normals outside. This should fix it as in your case the normals are inside not outside.

yeah shadow that's the problem but i did flip the normals outside already so i dont know what else could be wrong...<!--Session data-->

Do the following:
In Object Mode ( with object selected ):
ALT+R ( clear rotation )
ALT+G ( clear position )
ALT+S ( clear scaling )
In Edit Mode:
CTRL+N ( recalculate normals outside )

If this is done your mesh is going to be exported correctly. If then still wrong flipping happens check if you are really using the exported file ( source is picky about files ) or if you happened to have a strange configuration somewhere.

alright thanks alot, i did all that nad it works (except i didnt clear the scaling because it made it flat)<!--Session data-->

If the scaling messes it up just use CTRL+A to apply the scaling to the object. You can also apply position and rotation. Non-scaled and non-rotated objects are better suited for exporting in general.

alright thanks alot, this will help alot, that was the only problem i was having but now its all good <!--Session data-->