my mesh is turning black for no reason, please help!

Hi,
I have imported 3 dxf models into blender. The most complex one was completely black (no shading, just allover black) when in shaded mode and when I joined the models to make one mesh everything turned black.
It is in normal shaded mode (option just above wireframe) and is double sided so normals shouldn’t be a problem. I think this may be due to the complexity of the mesh although my computer isn’t having any trouble handling it.
So does anyone have any ideas??
I tried turning off double sided which sort of solves the problem but because the normals are mixed up parts are still black, so is there a way to align the normals??? (it would take far to long to do it manually)

I’ve just started using blender again after 1 1/2 years so I know the basics but i might need things spelt out quite clearly.

Thanks for your help,
sam

Hi,

In edit mode Select all vertices by pressing ‘A’, Then press Ctrl+N to make all your nornals point outwards or Ctrl+Shift+N to make them all point inwards! :smiley:

Regards
Fabrizio

that solve the problem,
thanks a lot.
Sam