Slic3r adding top layer that is not in model

I created this in Sketchup and can view it successfully in Meshlab. When I try to slice it with Slic3r 0.9.3, Slic3r adds a top layer that is not in the model. Any ideas why this might be so? Bug in Slic3r? Problem with the way I have Slic3r set up? Problems with my design?

There was a problem with the STL. If you load it up in Meshlab, pay attention to the inner most circle's doorway (wall cut) and you will notice that one side shows black no matter what direction you rotate the model.

I loaded it back into sketchup and while that section looked OK I decided to remake it by first deleting the 2 faces that made up the piece. Then I started to redraw it and bam the lid top up. You see it was there but was not visible because it was only missing that one little edge. So I deleted it and finished fixing the door edge.

Loaded it into Meshlab and it looked good. Sliced with Slic3r 0.9.5 and it worked (I tried before fixing and it sliced with a top just like you said.

So anyway here is the fixed version.

Edited 1 time(s). Last edit at 11/11/2012 03:11AM by tmorris9.

Thank you for finding that one reversed face! Once I reversed it in Sketchup, it exported fine as an STL, and Slic3r sliced it up properly!