Solo 630 Manual De Empleo página 20

BASIC RULES FOR SAFE OPERATION
1. Kick-back
- While cutting with a chain saw,
dangerous kick-back may occur.
– Kick-back is a reverse reacting force
created by the chain on the upper
nose quadrant contacting wood or
touching any other hard object.
– At that point, the saw can be forced
back in an arc or pushed against the
operator.
WARNING! DANGER OF INJURY! (fig. 16)
To prevent kick-back, follow these suggestions:
- Avoid cutting with the bar nose or tip. Closely watch the bar
nose at all times.
– Be very careful when continuing a previously started cut.
– Start the cut with the saw chain at speed.
– Always operate the saw with correctly sharpened chain. Ensure
uniform and correct height of the depth gauges on the cutters
of the chain.
– Never cut several branches with one cut. Exercise caution when
limbing and avoid contact with other branches.
- While cutting timber to length, avoid contact with other, close
logs.
Prohibited Cutting Practices:
- Never operate a chain saw at low visibility or poor light
conditions. Watch out for slipping in wet, icy or snowy
conditions. Increased danger of slipping exists on freshly de-
barked logs.
– Never work on unstable surfaces. Watch out for obstacles in
the work area and avoid stumbling. Always ensure secure
footing.
– Never cut above shoulder height.
- Never cut while standing on a ladder. (fig. 17). - Never climb
a tree with a chain saw.
- Do not overreach while cutting.
- Guide the chain saw in such a way that no part of your body
is within the extended cutting zone of the saw chain (fig. 18).
- Use the chain saw to cut wood only!
- Do not allow the running saw chain to touch the ground at
any stage.
- Never use the chain saw as a lever or scoop to remove wood
or other objects.
- Plunge or bore cutting as well as ripping should only be
performed by trained operators (increased danger of kick-
back).
– Ripping cuts along the length of the log should be started at
a very flat angle. Start this cut with caution since the bucking
spike cannot grip at that angle.
– Use caution when cutting split or twisted wood since torn off
wood splinters can be hurled by the chain towards the
operator. (Danger of injury).
- When cutting with the top of the guide bar, the chain saw
can be forced against the operator. It is best to cut with the
bottom side of the guide bar.(fig. 19).
FELLING TECHNIQUES
Exercise caution! Felling trees is dangerous and is a
skill that must be learned! If you are a beginner and
inexperienced, do not attempt felling. Attend a
special training course first. WARNING! Commence
the felling process only if the following criteria have
been met:
a) Only persons involved in the felling process should be in the
felling zone.
b) Ensure an obstacle free emergency retreat path for all persons
involved in the felling process. The escape route is at 45deg. angle
back and away from the line of fall.
c) The next, nearest felling zone should be at least two and one
half (2 1/2) tree lengths away. Prior to felling, always check the
line of fall and ensure that no other person, animals or objects
are within range of the danger zone (measured distance is 2 1/2
times the tree length). (fig. 20).
d) Clear base of tree of all foreign objects, under-growth, brush,
and branches. Secure solid footing to maintain solid stance. (risk
of stumbling - fig. 21).
Assessing the tree
- Check to which direction the tree is leaning.
– Check in which direction the tree is likely to fall. Is the tree
core rotten?
– Check wind direction and wind speed. In strong and gusty
winds all felling operations should be suspended.
Cutting buttress roots (fig. 22/-1,2,3)
– Remove largest buttress roots first. Start with cutting vertically,
then horizontally. Never trim rotten tree trunks before felling.
Note: The buttress root opposite the line of fall (fig.4) should be
saved to set wedges on.
Starting with the felling notch (fig. 23)
- The felling notch determines the line of fall and acts as a guide.
The notch should be at right angle to the trunk and in the
direction of the fall. Its size is approx. 1/3 to 1/5 of the size of
the trunk diameter and should be as close as possible to the
ground.
Execution (fig.23)
– Start with the upper part (roof) of the felling notch (1).
– Then proceed with the lower cut (notch base cut) in horizon-
tal direction until it meets up with the upper cut.
– Re-check direction of fall.
– If the felling notch requires correction, cut along its entire
width. On slopes, the lower notch base cut angle can be
increased to produce a wider, more open notch. This increases
the falling time and gives more control over the fall of the
tree.
– The felling cut (3) is started higher than the lower notch base
cut (2). This cut must be horizontal. Approx. 1/10 of the trunk
diameter between fell cut and felling notch should be left
uncut to act as a hinge(5).
– The hinge acts as a joint and provides control over the fall.
Never cut the hinge. Set wedges at the proper time.
– Secure the felling cut with plastic or aluminum wedges only.
Never use steel wedges.
– When felling, always stay sideways of the falling tree.
– When stepping back from the felling cut, watch out for falling
branches.
– When working on a slope, the saw operator must be above
or sideways to the tree being felled or worked on. (fig. 24).
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