Makita UC3551A Manuel D'instruction page 16

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. The
reason for this behavior is uneven sharpening of
the saw chain, or damage to one side only.
Sharpen the saw chain frequently, but remove only
a little material 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
Authorized or Factory Service Centers.
Sharpening criteria:
− All cutter length must be equal. Cutters of differing
length prevent the chain from running smoothly,
and may cause the chain to break.
− Do not sharpen the chain once a minimum cutter
length of 3 mm has been reached. A new chain
must then be fitted.
− 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 91PX: 0.65 mm (0.025")
2
1
1
3
1
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WARNING:
An excessive distance increases the risk of kick-
•
back.
− The sharpening angle of 30 ° must be the same on
all cutters. Differences in angle cause the chain to
run roughly and unevenly, accelerate wear, and
lead to chain breaks.
− The side plate angle of the cutter is determined by
the depth of penetration of the round file. If the
specified file is used properly, the correct side
plate angle is produced automatically.
− Side plate angle for each saw chain are as follows:
Chain blade 91PX: 80 °
1. Cutting length
2
2. Distance between
cutting edge and
depth gauge
3. Minimum 3 mm
30
1
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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 91PX: 4.0 mm (11/64")
− The file should only engage the cutter on the forward
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.
006927
− Guide the file as shown in the figure.
− The file can be guided more easily if a file holder
(optional accessory) is employed. The file holder
has markings for the correct sharpening angle of
30 ° (align the markings parallel to the saw chain)
and limits the depth of penetration (to 4/5 of the
file diameter).
30
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− After sharpening the chain, check the height of the
depth gauge using the chain gauge tool (optional
accessory).
16
1. Side plate angle
30
1