The red-hot block is struck and elongated using a Tsuchi (hammer), and folded back into the middle of its length, which is called a 'folding method of forging' and it is done repeatedly.
赤熱したブロックを鎚（つち）で叩き伸ばしては中央から折り重ねる「折り返し鍛練」を繰り返し行う。