Fig. 17

○ 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 (3–5 cm) above the edge of the notch. (Fig. 18)

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19

2120

Fig. 18

18.Felling direction

19.45° minimum notch opening

20.Hinge

21.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.

FELLING CUT, TRUNK DIAMETER MORE THAN TWICE GUIDE BAR LENGTH

Cut a large, wide notch. Then cut a recess into the center of the notch. Always leave a hinge on both sides of the center cut. (Fig. 19)

Fig. 19

Complete the felling cut by sawing around the trunk as in the Fig. 20.

Fig. 20

WARNING

These methods are extremely dangerous because they involve the use of the nose of guide bar and can result in kickback. Only properly trained professionals should attempt these techniques.

LIMBING

Limbing is removing the branches from a feller tree.

WARNING

A majority of kickback accidents occur during Iimbing.

Do not use the nose of the guide bar. Be extremely cautious and avoid contacting the log, other limbs or objects with the nose of the guide bar. Be extremely cautious of limbs under tension. They can spring back towards you and cause loss of control resulting in injury. (Fig. 21)

Fig. 21

Stand on the left side of the trunk. Maintain a secure footing and rest the saw on the trunk. Hold the saw close to you so that you are in full control of it. Keep well away from the chain. Move only when the trunk is between you and the chain. Watch out for spring back of limbs under tension.

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