Nakago (core) is finished with a Sen (a grinding tool) or a file, and for a Mekugi (fastening pin) hole used for securing the Tsuka (handle grip), usually one hole is drilled and two for a sword used for Iaido (Japanese martial art).
茎（なかご）は銑ややすりで形を整え、柄（つか）をはめる時に使用する目釘穴を普通は1つ、居合用の刀の場合2つ以上開ける。