(I had posted this thread without knowing there was a minimum-posts-before-you-can-post-useful-threads limit; hopefully this one will go through)
I have been working on a starfighter design with the end goal of having it printed at shapeways.com, a rapid prototyper in the Netherlands. It’s only my third Blender model, and my first attempt at making anything printable. I’ll try to summarize my process and my pitfalls.
Firstly, shapeways.com (like any RP company) has rules about the kind of mesh you can send them. It must be manifold, which for practical purposes means you can’t just model a wing, model a box, move it so it intersects with the wing and call it a fuselage. It’s all gotta be one piece. My choice of a custom starfighter miniature was intentional: It’s my own design, which bypasses the fanboy clamor of “ur doin it wrong”, it’s generally flat so the volume is minimized (shapeways charges by volume of material used), and it’s meant to be a gaming miniature (small size = less price and less need for detail).
As you can see from the attached pictures, I gave a go at doing paneling across the fuselage and wings. I figure if the detail prints, then great! And if not, it’s a shame, but I would have an idea of the possibilities then. The panels didn’t print and they were the cause of most of my headache trying to get the mesh manifold. It stems from the way I was trying to create the panels. The main mesh uses subsurf, mirror, and edge split modifiers. I wanted hard-edged panels that would still perfectly match up with the subsurfed main mesh surface for eventual joining and merging.
- First, I set up vertex groups in the un-subsurfed main mesh corresponding to each panel.
- Select a vertex group, leave edit mode, and duplicate the main mesh. Move the dupe to a new layer.
- Alt-C (apply modifiers*), delete original. *Do NOT apply the edge split modifier at all, ever - it tends to mess up manifoldness if it’s applied. Just keep edge split as a modifier.
- In edit mode, you’ll see that the panel area is still selected, and has been subsurfed to match the main mesh when it’s subsurfed. Separate § the panel’s faces and delete the rest of the duplicated, modifier-applied mesh.
- Move the panel back to the layer with the main mesh. At this point I extruded the panel a teeny bit, either moving + scaling or using Alt-S to shrink/fatten the raised panel.
Once I’d done this across the board, I had a main mesh with many separate objects basically sitting on top. Each object was manifold, I figured it’d be easy to simply join them all together.
WRONG! When I joined the panels and removed doubles, it came back with non-manifold lines around where each panel connected to the main mesh. What had happened was a stupid mistake. Each panel is a box, basically, and it sits atop the “box” of the main mesh. This creates a situation where there’s a top layer over a middle face that’s basically stuck in the volume of the mesh. I had to go through and delete all the main mesh faces that were covered by panels. Pain in the rear.
Anyway, with THAT done I looked to shapeways’ helpful support section on how to export your model to X3D format. NOTE: Shapeways has maximum dimensions, and X3D assumes 1 Blender unit = 1 METER. I had to scale my model WAAAAYYY down.
After that, it’s cake. Upload to shapeways, place an order, and around 10 days later I got my ships in Black Detail, White Detail, and White, Strong, and Flexible. The WSF material is lower-resolution and is grainier, but tougher. I think the White Detail won out, though. The Black Detail had some obvious printing lines in it while the White Detail seemed all around smoother. For such a small model, that’s the way I’d go.
The feeling of holding an actual object in your hand that previously only existed in your mind is truly exhilarating. I think I’m hooked on model-making. Still, I plan on forking this project. I need to reduce polys, remove unneeded detail, and exaggerate other details (like the engine thrusters and curve of the fuselage) for the physical model, but I also want to add more details and textures in order to make a model worth rendering.