Unfortunately your SketchUp model is NOT a manifold solid. To successfully 3d-print such a form it should be. See the attached image from SolidInspector² which list hundreds of issues [once the geometry - excluding the loose edge near the origin is grouped]. A 'solid' is a group/component which contains just edges and faces, and where every edge supports exactly two faces. So that means no nested containers like groups [you have 70], no faceless edges, no faces with just one edge [you have several] - like shelves, flaps and holes, no internal partitions where a edge would have three or more faces, no otherwise solid forms sharing an edge [with four faces], and finally no self-intersecting forms which might still report as 'solid' but which cannot be 3d-printed. I'm afraid you need a lot of manual fixing of this model. It cannot be 'automated', because the issues are so convoluted... [image: klN0_Capture.PNG]

Thanks, I'll see if I can make that work, though I do want to keep all the inner frame work. I was working bigger, maybe I'll try the Dave method. Really appreciate it.