Oregon 310-120 Original Instruction Manual page 21

310-120
Once you have sharpened the first cutter, raise
the motor unit (A) with the operating handle (1)
Loosen the vise handle (9) by depressing the red
button and rotating the vise handle counter-clockwise
Advance the chain forward to position the next
cutter to be sharpened, assuring that the chain stop
(8) is seated firmly against the rear of the cutter
Clamp chain again with the vise handle
(9) and sharpen the next cutter
Operating Instructions
21