24 Inspection and Maintenance
STIHL chain is manufactured with wear marks to help the
operator identify excessive wear. The wear marks depicted
above (1 - 4) must remain visible.
► Replace the chain if any wear marks are no longer visible.
► Check the 30° sharpening angle of the cutters with a
STIHL file gauge matching the pitch of the chain.
► If the sharpening angle is incorrect, file the cutters to a 30°
angle.
► If you are unable to achieve the proper angle, or suspect
you have not achieved the proper angle, have the chain
sharpened by an authorized STIHL servicing dealer.
An improperly filed chain can be very dangerous. It can
increase the potential for reactive forces, including kickback,
and also increase the magnitude of those reactive forces.
The chain pitch marking (a) is embossed in the area of the
depth gauge of each cutter.
The markings mean the following:
Marking (a)
1
2
3
4
6
7
0458-791-8621-C
a
Saw Chain Pitch
1/4"
.325"
3/8"
.404"
3/8" PICCO
1/4" PICCO
To sharpen the chain:
► Switch off the chain saw, engage the chain brake and
remove the battery.
► Select a chain file with a diameter matching the pitch of
the chain.
Other files are unsuitable and can result in improperly filed
chain, which can increase the potential and force of
kickback and other reactive forces.
► Clamp the guide bar if necessary to make filing easier.
► To advance the chain, first disengage the chain brake,
@ 16.2.
► Use a file holder.
File holders have markings that indicate the proper
sharpening angle.
► File all the cutters with an identical angle. Two or three
strokes of the file are usually sufficient for simple
resharpening. Remove a little material with each stroke.
Sharpening at varying or inconsistent angles or heights
can be very dangerous and may result in rough or uneven
running of the chain and increased wear, even to the point
of chain breakage. It also can increase the tendency and
force of kickback and other reactive forces.
► Guide the file horizontally at a right angle to the side
surface of the guide bar in accordance with the specified
angle.
► File only from the inside of the cutter outward.
► Lift the file on the backstroke. The file only sharpens on
the forward stroke.
► Do not file tie straps or drive links.
English
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