Comparative design methods for joints that will be joined together I want to 3D-print some parts that will be later joined together along a seam. When modeling these separate parts, what are some methods that work well with 3D-printed pieces? For example, if I were doing wood working, I might choose dowel and pin joints or mortise and tenon joints or glue overlapping pieces. What methods translate well into use with 3D-printed plastics? How does the answer change depending on the orientation of the joint along the printing direction?
One of my favorite techniques is to join pieces with screws, and include a tapered feature that helps align the parts. A single screw can give a very strong joint, that is well-aligned and won't twist. Another advantage is that such joints can be printed in any orientation, since the tapered feature can be designed with 45 degree angles.

Here is a cross-section example of such a joint: