Oregon 730-120 Original Instruction Manual page 30

Operation
9. Fold the grinding head down to its grinding
position.
10. The grinding depth for gullets is
recommended by the chain manufacturer.
To set it, turn the grinding depth knob
located on the back of the grinding head:
• clockwise, to grind shallower into the
gullet, or
• counterclockwise, to grind deeper into the
gullet.
11. Set the cutter top plate to equal lengths.
If the right (outer) and left (inner) cutters
are not sharpened to equal lengths, follow
these steps:
• Do a sharpening test on a test chain
according to the instructions in section
7.2, "Sharpening test"
• Make sure that the right and left cutting
teeth are sharpened to equal lengths. Use
the template provided with the machine
to measure. If they are not equally long,
turn the equal cutting teeth knob:
– clockwise to decrease the length of the
left cutter and increase the length of
the right cutter, or
– counterclockwise to increase the length
of the left cutter and decrease the length
of the right cutter.
• Repeat the sharpening test until the cutter
top plates are sharpened to equal lengths.
30
12. The diameter of the grinding wheel
decreases when it is used. To maintain
the grinding proportions, the grinding
wheel position must be changed when the
grinding wheel has been worn.
The grinding wheel centering knob is used
to center the grinding wheel over the chain.
The gullets should have equal depth on the
left and right cutting links.
– Sharpen a few links and then visually
inspect the result. If the grinding depth
is not equal on the gullets of the right
and left cutting links, continue to the
next step.
– Turn the grinding wheel centering knob
to move the grinding motor and the
wheel up or down. Set the arrow on the
scale to point to the number that
corresponds to the wheel diameter, as
displayed below. These scale numbers
are approximate and are only for
general guidance. Observe if the
grinding depth of right and left gullets
are equal for final adjustment.
Grinding wheel diameter:
5.9" (150 mm)
(new grinding wheels)
5.5" (140 mm)
5.1" (130 mm)
• Repeat steps 1-2 until the grinding depth
is equal.
13. To set the approximate grinding length,
turn the chain pusher adjustment knob:
• clockwise, to grind more, resulting in a
shorter cutter top plate, or
730-120
Scale:
1-3
3-5
4-6