Dolmar ES-154 Manual De Instrucciones página 16

– Consider the following with respect to each tree:
• Direction of lean;
• Loose or dry branches;
• Height of the tree;
• Natural overhang;
• Whether or not the tree is rotten.
– Consider the wind speed and direction. Do not carry
out felling work if the wind is gusting strongly.
– Trimming of root swellings: Begin with the largest
swellings. Make the vertical cut first, then the horizontal
cut.
– Cut a scarf: The scarf determines the direction in which
the tree will fall, and guides it. It is made on the side
towards which the tree is to fall. Cut the scarf as close
to the ground as possible. First make the horizontal cut
to a depth of 1/5 -1/3 of the trunk diameter. Do not
make the scarf too large. Then make the diagonal cut.
(Fig. 32)
– Cut any corrections to the scarf across its entire width.
– Make the back cut a little higher than the base cut of
the scarf. The back cut must be exactly horizontal.
Leave approximately 1/10 of the trunk diameter
between the back cut and the scarf.
The wood fibers in the uncut trunk portion act as a
hinge. Do not cut right through the fibers under any
circumstances, as the tree will otherwise fall
unchecked. Insert wedges into the back cut in time.
(Fig. 33)
– Only plastic or aluminum wedges may be used to keep
the back cut open. The use of iron wedges is
prohibited.
– Stand to the side of the falling tree. Keep an area clear
to the rear of the falling tree up to an angle of 45° either
side of the tree axis (refer to the "felling area" figure).
Pay attention to falling branches.
– An escape path should be planned and cleared as
necessary before cuts are started. The escape path
should extend back and diagonally to the rear of the
expected line of fall as illustrated in figure. (Fig. 34)
MAINTENANCE
CAUTION:
• Always be sure that the tool is switched off and
unplugged before attempting to perform inspection or
maintenance.
• Always wear gloves when performing any inspection or
maintenance.
• Never use gasoline, benzine, thinner, alcohol or the
like. Discoloration, deformation or cracks may result.
Carry out the maintenance work described below at
regular intervals. Warranty claims will be accepted only if
these operations have been performed regularly and
properly.
Only maintenance work described in this instruction
manual may be performed by the user. Any other work
must be carried out by DOLMAR authorized service
centers.
Cleaning the chain saw
Clean the saw regularly with a clean rag. The handles, in
particular, must be kept free of oil.
16
Checking the plastic housing
Carry out regular visual inspections of all parts of the
housing. If any parts are damaged, have them repaired
immediately and properly in DOLMAR authorized service
centers.
Sharpening the saw chain
CAUTION:
• Always withdraw the mains plug and wear safety
gloves when performing work on the saw chain.
Sharpen the saw chain when: (Fig. 35)
– 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
DOLMAR authorized service center.
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 492 (91PX): 0.65 mm (Fig. 36)
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 492 (91PX): 80° (Fig. 37)
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 492 (91PX): 4.0 mm
– 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.