I would be very curious under what provision of the constitution the Feds can ban manufacture of what is otherwise a legal product? As was noted in the article - you can make those parts legally by machining them. What is the difference between machining and 3D printing (hint: none, from a logical viewpoint).
logic thought is not the hobby of tyrants!
whats good for the goose..and all that.
They no longer follow the Constitution. After all, who is going to stop them?