Karsten - That's an interesting video and his cast aluminum piece based on a 3D print came out better than I expected.

Usually a piece like that that mates to other surfaces in a precision application is cast oversize and then machined to the final dimensions. Because his piece is not very large or complex, it would appear easier to simply machine it entirely from a single billet. But maybe he didn't have access to a milling machine. A piece that has complex curves would be a good candidate for his process.

Ed