A protection system for preventing foreign material from lodging in a channel between and/or damage to adjacent ceramic core features during a core processing operation is disclosed. The system includes a gasket sized and shaped to self-lock within the channel and prevent foreign material from lodging within the channel during the core processing operation. A method may include determining a geometrical characteristic of the channel and adjacent ceramic core feature; fabricating a gasket to fit and self-lock within the channel; positioning the gasket within the channel; and performing the core processing operation. The gasket prevents the foreign material from lodging in the channel, reducing subsequent damage to the ceramic core compared to the channel without the gasket.