Surface Border Error

I have difficulty creating solid groups/components. I use Solid Inspector 2 to help find problems.

For example, I open a new file. I draw a rectangle (or create using line tool). I then create group or component. Entity info indicates it is a Group, not a solid group. I then run Solid Inspector 2 and it reports a “Surface Border Error”. I then use the tab key to identify where the problem is located (image below). I cannot identify any problem using zoom or other tools such as Edge Tools 2, CleanUp, etc.

Should I not expect a simple rectangle, properly grouped, to be a solid group? Am I using Solid Inspector 2, incorrectly?

What am I doing wrong? How do I find the error and repair it.

Advance thank you for any assistance.

A solid in SketchUp is a group or component that encloses a 3D volume. A 2D shape isn’t a solid.

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Duh, embarrassed, but now enlightened. Had this strange feeling as I was creating this post, that I was missing some basic concept. :upside_down_face:

And Thanks …

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A valid solid in SketchUp is a group or component containing a surface (faces that share edges) that surrounds a volume with no holes and no spurious edges, flaps, or internal faces not needed for that surface. On such a closed surface, every edge bounds exactly two faces. A “surface border” is an edge or set of edges that have only one associated face, hence the surface stops there; there is a border.

In a 2D shape, the outer perimeter of the shape consists entirely of surface border!


Hence, Solid Inspector 2, identifying the entire perimeter as the problem, which is exactly correct. I see the light in this example. Now back to troubleshooting the other non-solid groups that I continually create.

I often find that Solid Inspector 2, identifies that problems exist but cannot fix the problems.

Thank you for the definition. Now, more learning on my part …

There are some kinds of flaws in a solid for which the fix is ambiguous. That is, there are multiple ways possible. Rather than taking a guess that would likely be wrong, solid inspector 2 just shows where they are and leaves you to decide what to do.

Not discrediting Solid Tools at all, it is a great, indispensable tool. I just need to change my SU behaviors to eliminate more issues from the start. For example, I get this error, routinely. I am guessing it is due to my grouping components and not correctly using the “Intersect Faces” command.

The Info box tells you what is going on, and how if you’re exporting to STL you need not worry about it.

Nested means that inside the group or component that you are inspecting are other groups and components. It’s the individual groups that you want to check if they are solid.