Top surface disappears after slicing

Hello wonderful Timkercad Community!

My problem is that the "skin" of the top layer of objects that I design disappears after the object files are sliced.  The objects appear fine both in Tinkercad and even look fine in the two 3D printer applications I have tried which are Cura and Moira. I have tried both STL and OBJ files.  In all cases the object files import to the slicing software clean with no perceptable problems.  However, each time I slice the object, the skin on top is gone revealing the honey-comb of the inner structure.  The skin on the sides of the object slice with out a Whaproblem.  

What I've tried:

I read in a Tinkercad forum that the grid granularity setting will dictate the thickness of the surface and so I experimented with a grid setting of 2mm.  

I've tried two slicing software apps - Moira and Cura  - same result

I've tried exporting to OBJ and STL

I've tested basic geometry objects from the menu with the same result.  

Thank you,



Please sign in to leave a comment.