Makita DCS 330 TH Owner's And Safety Manual page 27

All cutters must be sharpened to the same angle, 30°. Different
angles result in a roughly, irregularly running chain, increase
wear and tear and cause chain beakage.
The 85° front rake of the cutter results from the cut depth of the
round file. If the proper file is used in the right manner, the
correct front rake will be obtained automatically.
Files and how to work with them
Sharpen using a special file holder with a saw chain round file
dia. 5/32" (4.0 mm). Normal round files are not appropriate for
this work. Accessorie, not delivered with the chain saw.
The file should cut only when pushed forwards (arrow). Lift the
file when leading it backwards.
First sharpen the shortest cutter. The length of this cutter is
then the standerd for all other cutters of the chain.
Always guide the file horizontally (90° to the guide bar).
The file holder makes file guidance easier. It is marked for the
correct 30° sharpening angle (keep the marks parallel with the
chain when filing, see illustration) and limits the cut depth to the
correct 4/5 of the file diameter. Accessorie, not delivered with
the chain saw.
After having sharpened the chain, the height of the depth limiter
must be checked by means of a chain gauge. Accessorie, not
delivered with the chain saw.
Correct even the smallest excess height with a special flat
file (12). Accessorie, not delivered with the chain saw.
Round off the front of the depth limiter (13).
30°
12
D
E
4/5
F
13
G
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