Lista MPB-20 Manual De Instrucciones página 52

According to the type and construction of the appliance the following potential hazards might apply:
- Contact with exposed saw teeth of the saw chain (cutting hazards)
- Access to the rotating saw chain (cutting hazards)
- Unforeseen, abrupt movement of the guide bar (cutting hazards)
- Flung out of parts from the saw chain (Cutting / injection hazards)
- Flung out of parts of the work piece
- Skin contact with the oil.
- Loss of hearing, if no required ear protection used during work
SAVE THESE INSTRUCTIONS
Instructions concerning the proper techniques for basic felling, limbing, and cross-cutting
1. Felling a tree
When bucking and felling operations are being performed by two or more persons at the same time,
the felling operations should be separated from the bucking operation by a distance of at least twice
the height of the tree being felled. Trees should not be felled in a manner that would endanger any
person, strike any utility line or cause any property damage. If the tree does make contact with any
utility line, the company should be notified immediately.
The chain saw operator should keep on the uphill side of the terrain as the tree is likely to roll or slide
downhill after it is felled.
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 1.
Before felling is started, consider the natural lean of the tree, the location of larger branches and the
wind direction to judge which way the tree will fall.
Remove dirt, stones, loose bark, nails, staples and wire from the tree.
2. Notching undercut
Make the notch 1/3 the diameter of the tree, perpendicular to the direction of falls as illustrated in
Figure 1. Make the lower horizontal notching cut (W) first. This will help to avoid pinching either the
saw chain or the guide bar when the second notch (X) is being made.
3. Felling back cut
Make the felling back cut (Y) at least 50 mm higher than the horizontal notching cut as illustrated in
Figure 1. Keep the felling back cut parallel to the horizontal notching cut. Make the felling back cut so
enough wood is left to act as a hinge. The hinge wood keeps the tree from twisting and falling in the
wrong direction. Do not cut through the hinge.
As the felling gets close to the hinge, the tree should begin to fall. If there is any chance that the tree
may not fall in desired direction or it may rock back and bind the saw chain, stop cutting before the
felling back cut is complete and use wedges of wood, plastic or aluminium (Z) to open the cut and drop
the tree along the desired line of fall (
When the tree begins to fall remove the chain saw from the cut, stop the motor, put the chain saw down,
then use the retreat path planned (
Fig. 1
X
Z
Y
W
4. Limbing a tree
Limbing is removing the branches from a fallen tree. When limbing leave larger lower limbs to support
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