This part was made for the Tri-State Warbird Museum.  They had an original that had one of the "ears" broken off.  I was given permission to use it as a sample to make the pattern and core boxes from.  They also loaned me an intact and servicable original that doesn't belong to them to use as a sample.

The broken original was cut in half along the original parting line.  All holes were filled and the cut surfaces were built up with sheet wax to allow for the metal removed by the .062 in. thick slitter saw.  The internal areas were used to make "male" casts which were in turn used to make the cavities in the core boxes.

The broken "ear" stub was machined off and a new "ear" was fabricated from wood and epoxied on.

The intact original sample part is on the left and the BCA part is on the right.

Original on left, repro on right.