Exported models with what seems to be a phantom triangle?

Hello all,
I created a model, and when I 3D Print it, triangles begin to appear in the finished print with completely inverted properties. The printer is printing in exactly what should be empty space and leaving my design hollow.
After re-installing the 3D-Printer software, the only thing that could be wrong is SketchUp.The inverted “phantom triangle” doesn’t appear in SketchUp before export, and it doesn’t appear in the3D printing software.

If someone could figure out what the heck is going on, it would be of much help.


The 3d printer prints exactly what the triangles looks like when they are not softened/smoothed.
Can you share the model ?

The triangles don’t exist in the model I designed. In SketchUp, I never actually put any triangles in the model. The triangles appear when I print it.

If you post the model, or a link to the file on 3D Warehouse, there are plenty of people here that would love to take a look and help you out. Without the model, the best we can do is speculate…

If you are exporting as stl, triangles are inevitable as they are the only geometry that stl supports. So the question isn’t whether there will be triangles, it is why you aren’t getting ones that behave properly. Maybe some aspect of your model is confounding the stl exporter.

I am also getting inverted prints with one of the models. Any solution available?
Using Cura with Anycubic Kossel Delta printer.