PURPOSE: To make an incident angle of a medium to a blade simply and accurately alterable, by installing the blade for shaving off a projecting part on a tapelike magnetic recording medium free of vertical motion.

CONSTITUTION: A feed screw shaft 16 is rotated by drive of a motor via a spur gear 20 and two bevel gears 17 and 18, while a block being screwed with this feed screw shaft is moved up and down together with a blade 13, and a relative position of this blade 13 to an auxiliary bar 14 is varied. The relative position of this blade 13 in the vertical direction to the auxiliary bar 14 is varied like this, whereby incident angle of a web (tapelike magnetic recording medium) 2 to the blade 13 is altered. Thus the incident angle is delicately altered and adjusted, whereby a projecting part on the web 2 is efficiently shaven by the blade 3 without entailing any damage to a magnetic surface of the web 2.