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MS 290, MS 310, MS 390
English
39
Chain pitch
The chain pitch marking (a) is embossed
in the area of the depth gauge of each
cutter.
The diameter of file to be used depends
on the chain pitch – see table
"Sharpening tools".
The angles of the cutter must be
maintained during resharpening.
Sharpening and side plate angles
A Sharpening angle
STIHL saw chains are sharpened with a
30° sharpening angle. Ripping chains,
which are sharpened with a 10°
sharpening angle, are exceptions.
Ripping chains have an X in the
designation.
B Side plate angle
The correct side plate angle results
automatically when the specified file
holder and file diameter are used.
The angles must be identical for all
cutters in the saw chain. Varying angles:
Rough, uneven running of the saw
chain, increased wear – even to the
point of saw chain breakage.
File holder
N
Use a file holder
Always use a file holder (special
accessory, see table "Sharpening tools")
when sharpening saw chains by hand.
File holders have markings for the
sharpening angle.
Use only special saw chain files! Other
files are unsuitable in terms of shape
and type of cutting.
To check the angles
STIHL filing gauge (special accessory,
see table "Sharpening tools") – a
universal tool for checking sharpening
and side plate angles, depth gauge
setting, and tooth length, as well as
cleaning grooves and oil inlet holes.
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
689BA027 KN
a
Tooth shapes
Angle (°)
A
B
Micro = semi-chisel tooth,
e. g., 63 PM3, 26 RM3,
36 RM
30
75
Super = full chisel tooth,
e. g., 63 PS3, 26 RS,
36 RS3
30
60
Ripping chain, e. g.,
63 PMX, 36 RMX
10
75
A
B
689BA021 KN
689BA025 KN
001BA203 KN