Making a 3D model that will print

Modeling for 3D printing is the same as any other modeling in Blender. But there are no cheats. You have to be precise and orderly. Using the Mesh Analysis panel hinted at the kinds of things we are looking to eliminate, such as intersecting polygons, holes in the model, sharp edges, polygons that aren't flat, and details that are too small or too delicate. We are making objects for the real world and must always consider that. We have to remember what material we are going to make the part with, how large it is, and how precisely we have to fit it together with other objects.

3D printing is an art, not a science. Many times, the only thing to do is to try something and see if it works. A file that works with one printer or material may fail with another. But there are considerations that are universal. The two big words for 3D printing are watertight and manifold.

Making a watertight model

With 3D printing, we are trying to bring our Blender objects into the...