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Prompted by recent discussions of 3D printing fossils, I want to start a topic for it. As ZiggieCie points out, 3D printing will have an increasing impact on the fossil world. The recent publication of the discovery of Homo naledi, accompanied by 86 3D-printable bone specimens, surely marks an inflection point in the scientific sharing of 3D fossil data. Popular sites describe how to print your own H. naledi fossils. Folks have shared prints of their own. Below is a 3D print from the authors of the study. Here on TFF, Cris himself has explored using photogrammetry to generate 3D data for a whale vertebra. (Photogrammetry is the use of photographs to make measurements, particularly precise distance measurements between surface points.) That prompts the question: can anything for which we have 3D data be 3D printed? The answer is: not without significant work. 3D viewable data and 3D printable data are very different. You can view 3D data that's pure fantasy. Consider a geometrically ideal plane with mathematically zero thickness. Easy to view on a computer screen. Quite impossible to produce in reality. And 3D printing is all about reality. The key idea is that, to 3D print an object, it must be a solid three-dimensional object that is watertight. Technically, it must be manifold: every object must be composed of polygons that share each edge with exactly one other polygon. Non-manifold objects can't be 3D printed. The 3D printing site Shapeways has a detailed tutorial on fixing non-manifold models. From personal experience, I can say that fixing manifold issues, even with models designed for 3D printing that have gone off the rails, can be a tremendous pain. Tools are getting better for fixing non-manifold models. At this stage in the development of the technology, it's still critical to know what manifold objects are. So for Cris's photogrammetry data, it can be visualized easily, but for 3D printing, it's a big deal that the bottom of the whale vertebra wasn't scanned. The model just ends in midair, meaning it's not manifold, and can't be 3D printed without repair work. Hope to hear more from others who have tried 3D printing. I've posted a topic on 3D printing a trilobite sculpture -- not fossil data -- which may also be helpful if you've never seen a 3D print being made before.