I believe my model is now solid having deleted all interior faces and I don’t think there are any stray lines or edges. Running Solid Inspector2 confirms by only giving me a “Surface Border 1” message. There is nothing in bold red on my model indicating where, if any problem, is.
So do I ignore this message if I want to try 3d printing? I have some more inspecting to do in case I didn’t xray every single little crevice, but in general, is this something that for sure will prevent printing or is it a false alarm sometimes?