semitransparent model

[Gerd]

I printed severel models generated in blender with the same settings and all were fine.
Another model looks fine in blender. When I reimport the stl-file to blender I get a nice model again. But if I import the stl-file to Simplify3D I get a semitransparent preview. Depending on rotation some of the models parts are visible or not. It is not possible to generate useful support. Some manually generated support structures penetrate the lower wall of model, supporting the upper wall of the modell. Generating automatic support isn't possible at all.
Has anybody an explantation?

Newest update installed, works with other modells.
Attachments: model form stl generated and reiported in blender, imported stl in Simplify3d

Thanks
Gerd

[JoeJ]

That probably means a bunch of your surfaces are backwards. If the triangles are facing the wrong way, they won't show up in the 3D render.

[Gerd]

Now I found the reason for the problem. In blender all normals point outside as they should. But after export, the normals of the .stl all point inside the mesh. Why? I don't know. With none of my other models I had such problems. The solution is to flip the normals in blender. Then the normals point outside in Simplify3D and everything works fine.
Gerd