Stihl MS 171 Instruction Manual page 37

29 Maintaining and Sharpening the Saw Chain
► Guide the file: horizontally (at a right angle to
the side surface of the guide bar) in accord‐
ance with the specified angle – according to
the markings on the file holder – rest the file
holder on the tooth head and the depth gauge
► File only from the inside outward
► The file only sharpens on the forward stroke –
lift the file on the backstroke
► Do not file tie straps and drive links
► Rotate the file a little periodically in order to
avoid uneven wear
► To remove file burr, use a piece of hardwood
► Check angle with file gauge
All cutters must be equally long.
With varying cutter lengths, the cutter heights
also vary and cause rough running of the saw
chain and chain breakage.
► All cutters must be filed down equal to the
length of the shortest cutter – ideally, one
should have this done by a servicing dealer
using an electric sharpener
0458-533-0121-E
29.7
90°
The depth gauge determines the depth to which
the cutter penetrates the wood and thus the chip
thickness.
a Required distance between depth gauge and
cutting edge
When cutting softwood outside of the frost sea‐
son, the distance can be increased by up to
0.2 mm (0.008").
Chain pitch
Inches
1/4 P
1/4
3/8 P
0.325
3/8
0.404
29.8
The depth gauge setting is lowered when the
cutter is sharpened.
► Check the depth gauge setting after each
sharpening
► Lay the appropriate file gauge (1) for the chain
pitch on the saw chain and press it against the
cutter to be checked – if the depth gauge pro‐
trudes past the file gauge, the depth gauge
must be reworked
Saw chains with humped drive link (2) – upper
part of the humped drive link (2) (with service
Depth gauge setting
Depth gauge
Distance (a)
(mm) mm
(6.35) 0.45
(6.35) 0.65
(9.32) 0.65
(8.25) 0.65
(9.32) 0.65
(10.26) 0.80
Lowering the depth gauges
1
English
a
(Inches)
(0.018)
(0.026)
(0.026)
(0.026)
(0.026)
(0.031)
2
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