METHOD OF MANUFACTURING SQUARE-SHAPED BOARD

PROBLEM TO BE SOLVED: To remove cracks caused by the unevenness at the flank or the inequality in thickness of a square-shaped board, when manufacturing the square-shaped board by slicing a square-shaped ingot. SOLUTION: The square-shaped ingot A is transferred to an upward support 8a on the truck 8 of a carriage means 7 with a transfer mechanism 5 after rotation by 45 deg. by an attitude converting mechanism 3; and the two flanks directed obliquely upward are polished with the polishing jig 12a and 12b for rough polishing and the polishing jigs 13a and 13b for finish polishing of a polishing processor 11, while shifting the ingot A with a pusher 10; it is transferred to an inverting mechanism 14 with a transfer mechanism 15 so as to invert the top and bottom of the ingot A; and then the ingot A is re-transferred onto the upward support 8a of the truck 8 of the carriage means 7, and the left two flanks directed obliquely upward are polished with the polishing processor 11, while shifting the ingot with the pusher 10; and the ingot is transferred to a posture converting mechanism 4 with the transfer mechanism 15, and the ingot A is turned by 45 deg. by the attitude converting mechanism 4.