Komatsu GD555-5 Operation & Maintenance Manual page 178

OPERATION
OPERATION
CHANGING BLADE CUTTING ANGLE
When power tilt control lever (5) is pushed forward (A), the cutting
angle becomes larger; when it is pulled back (C), the cutting angle
becomes smaller.
When cutting hard soil (D), make the cutting angle larger.
When cutting soft soil (E), make the cutting angle smaller.
The distance between the cutting surface and the blade edge can
be changed, so it is possible to carry out fine adjustment of the
height of the cutting surface.
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