17 ENGLISH
MAINTENANCE
CAUTION:
Always be sure that the tool is
switched off and the battery cartridge is removed
before attempting to perform inspection or
maintenance.
CAUTION:
Always wear gloves when perform-
ing any inspection or maintenance.
NOTICE:
Never use gasoline, benzine, thinner,
alcohol or the like. Discoloration, deformation or
cracks may result.
To maintain product SAFETY and RELIABILITY,
repairs, any other maintenance or adjustment should
be performed by Makita Authorized or Factory Service
Centers, always using Makita replacement parts.
Sharpening the saw chain
Sharpen the saw chain when:
•
Mealy sawdust is produced when damp wood is
cut;
•
The chain penetrates the wood with difficulty, even
when heavy pressure is applied;
•
The cutting edge is obviously damaged;
•
The saw pulls to the left or right in the wood.
(caused by uneven sharpening of the saw chain or
damage to one side only)
Sharpen the saw chain frequently but a little each time.
Two or three strokes with a file are usually sufficient for
routine resharpening. When the saw chain has been
resharpened several times, have it sharpened in our
authorized service center.
Sharpening criteria:
WARNING:
An excessive distance between
the cutting edge and depth gauge increases the
risk of kickback.
2
2
1
1
3
1
Fig.34
►
1.
Cutter length
2.
Distance between cutting edge
and depth gauge
3.
Minimum cutter length (3 mm)
— All cutter length must be equal. Different cutter
lengths prevent the saw chain from running
smoothly and may cause the saw chain to break.
— Do not sharpen the chain when the cutter length
has reached 3 mm or shorter. The chain must be
replaced with new one.
— The chip thickness is determined by the distance
between the depth gauge (round nose) and the
cutting edge.
— The best cutting results are obtained with following
distance between cutting edge and depth gauge.
•
Chain blade 90PX : 0.65 mm
•
Chain blade 91PX : 0.65 mm
30
30
55
55
Fig.35
— The sharpening angle of 30° must be the same on
all cutters. Different cutter angles cause the chain
to run roughly and unevenly, accelerate wear, and
lead to chain breaks.
— Use a suitable round file so that the proper sharp
-
ening angle is kept against the teeth.
•
Chain blade 90PX : 55°
•
Chain blade 91PX : 55°
File and file guiding
— Use a special round file (optional accessory) for
saw chains to sharpen the chain. Normal round
files are not suitable.
— Diameter of the round file for each saw chain is as
follows:
•
Chain blade 90PX : 4.5 mm
•
Chain blade 91PX : 4.0 mm
— The file should only engage the cutter on the for
-
ward stroke. Lift the file off the cutter on the return
stroke.
— Sharpen the shortest cutter first. Then the length
of this shortest cutter becomes the standard for all
other cutters on the saw chain.
— Guide the file as shown in the figure.
1
2
Fig.36
►
1.
File
2.
Saw chain
