PURPOSE: To ensure smooth cutting of a work piece even if it is thin like a flat bar by drawing a super steel circular saw to the work piece while the saw is stricken in contact with it obliquely with a certain angle maintained.

CONSTITUTION: A material in a sheet form such as a flat bar is supported by a holding device 12, and is set such that a circular saw 10 is accurately positioned at a cutting position. In this case, a moving stand 4 is in an elevated position on the upper end side of a guide rail 3. A screw rod 5 is rotated to the positive direction by a motor 7 for sliding the moving stand 4 over a guide rail 3 so as to lower it down at a set speed. A circular saw 10 rotated by the motor 9 is drawn close to a work piece and is stricken in contact with the work piece with about 30° maintained. Accordingly, the blade tip of the circular saw 10 will never resonate whereby the work piece can be smoothly cut out even if it is thin.