Abstract: A secondary datum scheme is used for identifying the location of the core-produced internal geometry of hollow investment cast metal parts that are made using a free-floating core design for implementing complex internal structural features. A set of datum pads are cast on a removable portion of the core print out to provide the secondary reference system. This secondary reference system precisely establishes the location of the core-produced internal geometry of the part exclusive of any fixed external primary datum structure/system so that, for example, precision machining and gauging may be performed upon such internal features during subsequent fabrication steps.

Abstract: A method for forming inserts for steam cooled hot gas path components involves casting the inserts and laser drilling the cast inserts with the ceramic casting core still in place. Thereafter, the ceramic core is removed through the use of a leachant. By laser drilling the holes with the ceramic core still in place, the ceramic core acts as a backer during the laser drilling which results in more precise drilling of the inserts and reduced processing time.