English
When cutting with the bottom part of the chain the reactive force will pull the saw away from you towards the wood you are cutting.
The saw will control the feeding speed and sawdust will be directed towards you. (Fig. 19)
Fig. 19
○When cutting with the upper part of the chain the reactive force will push the saw towards you and away from the wood you are cutting. (Fig. 20)
Fig. 20
○ There is a risk of kickback if the saw is pushed far enough so that you begin to cut with the nose of the bar.
The safest cutting method is to cut with the bottom part of the chain. Sawing with the upper part makes it much more difficult to control the saw and increases the risk of kickback.
○ In case the chain locked, immediately release the throttle lever.
If the throttle lever keeps rotating at high speed with the chain locked, the clutch will overheat causing trouble.
NOTE
Always keep the spiked bumper face to a tree, because the chain may suddenly be drawn into a tree.
Felling
Felling is more than cutting down a tree. You must also bring it down as near to an intended place as possible without damaging the tree or anything else. Before felling a tree, carefully consider all conditions which may effect the intended direction, such as:
Angle of the tree. Shape of the crown. Snow load on the crown.
Wind conditions. Obstacles within tree range (e.g., other trees, power lines, roads, buildings, etc.).
WARNING
○ Always observe the general conditions of the tree. Look for decay and rot in the trunk which will make it more likely to snap and start to fall before you expect it.
○ Look for dry branches, which may break and hit you when you are working.
Always keep animals and people at least twice the tree length away while felling. Clear away shrubs and branches from around the tree.
Prepare a path of retreat away from the felling direction.
Basic rules for felling trees
Normally the felling consists of two main cutting operations, notching and making the felling cut. Start making the upper notch cut on the side of the tree facing the feeling direction. Look through the kerf as you saw the lower cut so you do not saw too deep into the trunk. The notch should be deep enough to create a hinge of sufficient width and strength. The notch opening should be wide enough to direct the fall of the tree as long as possible. Saw the felling cut from the other side of the tree between one and two inches
240
251
27 | 2226 |
3 |
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Fig. 21 |
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24.Felling direction
25.45° minimum notch opening
26.Hinge
27.Felling cut
Never saw completely through the trunk. Always leave a hinge.
The hinge guides the tree. If the trunk is completely cut through, you lose control over the felling direction.
Insert a wedge or a felling lever in the cut well before the tree becomes unstable and starts to move. This will prevent the guide bar from binding in the felling cut if you have misjudged the falling direction. Make sure no people have come into the range of the falling tree before you push it over.
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