Black+Decker GK1740 Manual De Instrucciones página 24

24 • ENGLISH
Auto-stop chain brake (Fig. D)
f This tool is fitted with an auto-stop chain brake
assembly (4) which will stop the chain (6) within 150
ms each time you release the rear trigger, or if
kickback should occur. The chain brake assembly (4)
should be tested before every use.
How to set the chain brake (Fig. D)
f Make sure that the tool is disconnected from the
mains supply.
f Pull the front guard/chain brake assembly (4) back
into the "set" position marked
The tool is now ready to use.
How the anti-kickback chain brake works
In the event of kickback, your left hand comes in contact
with the front guard, pushing it forw ards, toward the
workpiece, and stops the tool within 150 ms.
How the inertia activated chain brake works
The front guard/chain brake assembly (4) is activated
when the front hand guard is pushed forward, either
manually, by the back of the users hand or by its own
weight. The advantage of the inertia brake is that it is
activated by a severe kickback, e.g. When the chain
(6) hits metal, even if the users hand does not contact
the front guard, i.e. when the chainsaw is in the felling
position.
How to test the anti-kickback chain brake (Fig. D)
f Grip the tool firmly in both hands on a firm surface
make sure the saw chain (6) is clear of the ground and
switch on (see" How to switch the chainsaw on").
f Rotate your left hand forward around the front handle
so that the back of your hand comes in contact with
the front guard/chain brake assembly (4) and pushes
it forwards, toward the workpiece (Fig. D). The saw
chain (6) should stop within a few fractions of a second.
To reset after the operation of the front guard/chain brake
assembly (4):
f Follow the instructio ns for "How to set the chain brake".
Note: It will not be possible to switch the tool on if the front
guard/chain brake assembly (4) is not in the "set" position.
Note: Avoid re-starting the tool unti lyou hear the motor
come to a complete rest.
Note: If the saw chain (6) does not come to rest
immediately then this indicates that it n eeds tensioning
(see "Fitting the guide bar and chain").
How to switch the tool on (Fig. G)
f Grip your chainsaw firmly with both hands. Push the
lock- off button (2) forward and then push the on/off
switch (1) to start.
f When the motor starts, remove your thumb from the
lock button (2) and grip the handle firmly.
(Fig. D).
Do not force the tool - allow it to do the work.
It will do a better and safer job at the speed for which it is
designed. Excessive force will stretch the saw chain (6).
If the saw chain (6) or guide bar (7) becomes jammed:
f Switch the tool off.
f Disconnect the tool from the mains supply.
f Open the cut with wedges to relieve the strain on the
guide bar (7). Do not try to wrench the chainsaw free.
Start a fresh cut.
Felling (Fig. I - K)
Inexperienced users should not attempt to fell trees. The
user may suffer injury or damage to property as a result of
failure to control the direction of fall, the tree may splinter
or damaged / dead branches may fall during cutting.
The safe distance between a tree to be felled and
bystanders, buildings and other objects is at least 2 1/2
times the height of the tree. Any bystander, building or
object within this distance is at risk from being struck by
the tree when felled.
Before attempting to fell a tree:
f Make sure that there are no local by-laws or
regulations that would prohibit or cont rol the felling
of the tree.
f Consider all conditio ns that may affect the direction
of fall, including:
f The intended direction of fall.
f The natural lean of the tree.
f Any unusual heavy limb structure or decay.
f Surrounding trees and obstacles including overhead
lines and underground drains.
f The wind speed and direction.
re-plan a safe exit from falling trees or branches. Make
sure that the exit route is clear of obstacles that would
prevent or hinder movement. Remember wet grass and
freshly cut bark is slippery.
Do not attempt to fell trees where the tree diameter is
greater than the cutting length of the chainsaw.
A direction notch is cut to determine the direction of fall.
A horizontal cut is made to a depth of between 1/5th and 1/
3rd of the diameter of the tree, perpendicular to the line of
fall at the base of the tree (Fig. I). The second cut is made
from above to intersect with the first and make a notch of
about 45°.
Make a single horizontal felling cut from the other side 1-2
inches above the centre of the direction notch (Fig. J). Do
not cut through to the direction notch, you could lose control
of the direction of fall.
Drive a wedge or wedges into the felling cut to open it and
drop the tree (Fig. K)
Pruning trees
Make sure that there are no local by-laws or regulations
that would prohibit or control the pruning of the tree limbs.