Hello! I was preparing a hollow cube (4x4x4 cm) in Blender. When I uploaded it as STL the Shapeways servers did consider it as hollow giving it a volume of 33 cm3. However, when I did a UV-mapping with JPG images and uploaded it as VRML97 (zipped with image files) the server returned a value of 64cm3, which is a volume of a solid cube of that size. All other parameters were as before, only UVmaps were added. I played with various ways of making a hollow object but every time I apply UVmaps tha volume jumps to that of a solid object. Do you possibly know why this is happening and how can I overcome this obstacle? Many thanks for help!