Object Filled During Save


I’m working on an object to be 3D printed and adding some text to the bottom of the object.

The text is inset from the flat plane of the base. Looks ready to go…

But when I save the file one last time before exporting the model, suddenly one or two of the letters are filled in! Why did the letter “a” here get filled in when I saved the file?

I’m mystified why just one or two of the letters were changed by saving the file. After saving, the outline of the letter “a” is missing a tiny segment so that it merged with the flat plane around. I connected the missing part of the outline and then was able to delete the surface of the “a”, leaving only the inset portion of the letter, but when I saved the file again, the letter spontaneously filled itself in again.

How do I prevent this from happening? Why is the shape suddenly drawing itself in? And why is it only affecting seemingly random letters of the text?


You might try unchecking “automatically fix problems when they are found” in
This may have to do with some very small faces that Sketchup doesn’t tolerate well.
There could be some small modeling errors causing this as well.



I had wondered about that preference, and I had turned it off already. But for good measure I tried turning off the “Automatically check models for problems” option now. And that seems to have solved the problem!
Thanks much for the tip!


There must be an underlying fault in the geometry of your model. It could be that the surface is twisted but at such a small scale that you don’t really see it. You can probably get away with it but it would be better to know why and fix it.
If you attach the model I’m sure someone will find the fault for you so you know for the future.