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22.1
Replace the chain sprocket
201
1BA045 KN
–
replace after using two saw chains or sooner
–
if the wear marks (arrows) on the sprocket are
deeper than approx. 0.5 mm since this would
reduce the life of the chain. You can use a
gauge (special accessory) to check the depth
of the wear marks.
Using two saw chains in alternation helps pre‐
serve the chain sprocket.
STIHL recommends use of original STIHL chain
sprockets in order to ensure optimal functioning
of the chain brake.
Have the chain sprocket replaced by an author‐
ized dealer. STIHL recommends that mainte‐
nance and repair work be carried out only by
authorised STIHL dealers.
23 Maintaining and Sharpen‐
ing the Saw Chain
23.1
Sawing effortlessly with a prop‐
erly sharpened saw chain
A properly sharpened saw chain cuts through
wood effortlessly even with very little pushing.
Never use a dull or damaged saw chain – this
leads to increased physical strain, increased
vibration load, unsatisfactory cutting results and
increased wear.
► Clean the saw chain
► Check the saw chain for cracks and damaged
rivets
► Replace damaged or worn chain components
and adapt these parts to the remaining parts in
terms of shape and level of wear – rework
accordingly
Carbide-tipped (Duro) saw chains are especially
wear-resistant. For an optimal sharpening result,
STIHL recommends STIHL servicing dealers.
WARNING
Compliance with the angles and dimensions lis‐
ted below is absolutely necessary. An improperly
sharpened saw chain – especially depth gauges
that are too low – can lead to increased kickback
tendency of the chain saw – risk of injury!
23.2
Chain pitch
689BA027 KN
a
The chain pitch marking (a) is embossed in the
area of the depth gauge of each cutter.
Marking (a)
Chain pitch
Inches
mm
7
1/4 P
6.35
1 or 1/4
1/4
6.35
6, P or PM
3/8 P
9.32
2 or 325
0.325
8.25
3 or 3/8
3/8
9.32
4 or 404
0.404
10.26
The diameter of file to be used depends on the
chain pitch – see table "Sharpening tools".
The angles of the cutter must be maintained dur‐
ing resharpening.
23.3
Sharpening and side plate
angles
A
B
689BA021 KN
A Sharpening angle
STIHL saw chains are sharpened with a 30°
sharpening angle. Ripping chains, which are
sharpened with a 10° sharpening angle, are
23 Maintaining and Sharpening the Saw Chain
English
0458-506-0121-C
29