Double Hollows

[skullforger]

Hi,

Whenever I try to hollow a model with the Edit > Hollow operation, I end up with just a hollow cavity under the 'skin' of the object, but still solid inside. It's as if there is just a hollow layer instead of the object completely being hollow. The pictures below will hopefully make this clearer.

Below is the model before hollowing. I check the condition with Plane Cut. 

 

 

Below is during the hollow operation. The preview seems to show correct hollowing.

But when I finally perform the operation and then check again with plane cut, you see that the model still has a solid inside hollow cavity... 

I must be doing something wrong, but I have no idea. My normals are correct (I think). Any help would be greatly appreciated.

[MagWeb]

Hmm strange... One can see two interior surfaces in the PlaneCut image.

Did you run Hollow twice or is there some interior surface in your source object?

You might try:

SELECT some tiny area on your source mesh using the select brush in UnwrapBrush mode > Hit E to expand the selection to connected faces > Hit I to invert the selection (Selection is not visible now)> Hit X to discard interior cavities.

or 

Run EDIT/SeparateShells and discard all objects but the exterior surface.