Conceptually, FDM 3D printing is quite a simple process: you define a set of volumes in 3D space, then the slicing software takes a cut through the model at ever-increasing heights, works out where ...

[DaveMakesStuff] demonstrates a great technique for 3D printing a sphere; a troublesome shape for filament-based printers to handle. As a bonus, it uses a minimum of filament. His ideas can be applied ...