A method of forming an airfoil (12), including: abutting end faces (72) of cantilevered film hole protrusions (64) extending from a ceramic core (50) against an inner surface (80) of a wax die (68) to hold the ceramic core in a fixed positional relationship with the wax die; casting an airfoil including a superalloy around the ceramic core; and machining film cooling holes (34) in the airfoil after the casting step to form an pattern of film cooling holes comprising the film cooling holes formed by the machining step and the cast film cooling holes (102) formed by the film hole protrusions during the casting step.