Sapwood Cuts; Felling Back Cut - Stihl MSA 220 C Manual De Instrucciones

English
8.6.5

Sapwood Cuts

Sapwood cuts help prevent soft woods in summer from
splintering when they fall:
► Make cuts at both sides of the trunk, at the same height as
the subsequent felling back cut.
► Cut no more than the width of guide bar.
8.6.6

Felling Back Cut

WARNING
￭ If the tip of the bar contacts a wedge that has been used
to help keep the kerf or cut open, it may cause kickback.
Wedges should be of wood or plastic and never steel,
which can damage the chain.
￭ Whichever felling method you select, never cut through
the hinge when making your felling back cut. The hinge
helps control the fall of the tree. Cutting through the hinge
will eliminate the feller's ability to control the tree's fall and
may result in serious or fatal personal injury or property
damage.
￭ In order to reduce the risk of personal injury, never stand
directly behind the tree when it is about to fall, since part
of the trunk may split and come back towards the operator
(barber-chairing), or the tree may jump backwards off the
stump.
30
8 Proper Techniques for Basic Bucking, Limbing, Pruning and Felling
￭ Always keep to the side of the falling tree. When the tree
starts to fall, withdraw the bar, release the trigger switch,
engage the chain brake and walk away briskly on the pre-
planned escape path.
￭ Watch out for limbs falling from the felled tree.
￭ Be extremely careful with partially fallen trees. When the
tree hangs or for some other reason does not fall
completely, set the saw aside and pull the tree to the
ground with a cable winch, block and tackle or tractor.
Trying to cut it down with your saw is extremely dangerous
and may result in serious or fatal injury. Trees of this
nature can fall suddenly and often are under tension.
The tree is brought down with the felling back cut (D).
For both conventional and open-faced notches:
► Begin 1 to 2 in. (2.5 to 5 cm) higher than the bottom of the
felling notch.
► Cut horizontally toward the felling notch.
► Leave approximately 1/10 of the diameter of the tree
uncut. This is the hinge (E) that will help control the fall of
the tree.
► Do not cut through the hinge because you could lose
control of the direction of the fall.
► If necessary, wedges can be driven into the felling back
cut to keep the cut open and to help control the direction
of the fall. For example, if a tree tends to "sit back,"
causing a bind of the saw, wedges can be used to re-
position it.
D
D
0458-795-8621-C