Additive on Additive
This additively manufactured metal part receives fnish milling for dimensional tolerance
and fnish. The fxture that holds the part for machining was also made additively (using a
3D printer). The part is a sternal closure—essentially a buckle for closing the rib cage after
surgery. Its locking mechanism relies on the slots arrayed around the part's inner circle,
and these slots are angled rather than square with the part. Thus, the part's geometry is
3D rather than 2D, making it too complex to be made through a cutting process such as
wire EDM. Siemer says the angled features achieve a lock so secure that an assembled
closure mechanism would be needed to match it. In short, if not for additive manufacturing, this component would need to be several pieces instead of just one piece.
AdditiveManufacturingInsight.com August 2013 — 9