Makita DUC302Z Manuel D'instruction page 15

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 behaviour 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 a
MAKITA specialist repair shop.
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 90PX: 0.5 mm (0.016")
Chain blade 91PX: 0.65 mm (0.025")
2
1
3
1
► 1. Cutting length 2. Distance between cutting edge
and depth gauge 3. Minimum 3 mm
2
1
15 ENGLISH
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 90PX: 75 °
Chain blade 91PX: 80 °
30
1
► 1. Side plate angle
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 (3/16")
Chain blade 91PX: 4.0 mm (11/64")
— 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.
30
1