So you are joking... but 3d printing allows us to manufacture new and different parts because 3d printing is ADDITIVE and "milling" is REDUCTIVE (removing?).

There is one technique where you have gell filled with aluminum particles. You then use lasers to heat up specific areas. It melts/fuses the aluminum and burns off the gell. In the end you have cast aluminum in any shape that is as hard as if you had milled it from a solid block.