Operation: Felling
AM24480,0000344 -19-06SEP21-1/1
Double-cut technique
CAUTION: While a number of factors can affect
the felling control and direction of large or
double-cut trees, uncontrolled felling can create
a hazardous situation. To reduce the risk of this
occurring, ensure you use work site planning and
management methods when felling such trees.
NOTE: Due to the poor form sometimes encountered
during felling and processing, it is sometimes
necessary to use special techniques to handle
stems safely, with minimal damage to the carrier.
Double-cuts allow trees to fall freely, while minimising
damage to the butt. To prevent damage to the saw bar, and
to limit the incidence of ‘barber chairs’, it is recommended
you use double-cuts on trees with a larger diameter.
For larger trees, it is recommended you use two cuts: a
front or compression cut (1); and a back or release cut
(2). This approach prevents the top or tip of the cutting
unit from travelling over the direction in which the tree
falls, which, in turn, prevents damage caused by the tree
moving forward and down.
Position the felling head so it is located at the front or
in the desired fall-direction of the tree. Then, make the
front cut (1); ensure you do not apply any side or upward
pressure. When the cutting unit is square with the tree’s
fall-direction, finish the cut.
Make the back cut (2) so that it is higher than the front cut;
this will allow the tree to fall off a level and avoid splitting
wood towards the cutting unit. While making the cut,
apply a small amount of side and upward pressure to the
tree; this level should be determined according to the lean
and size of the tree.
Take care with the alignment of the two cuts, as there may
be ‘holding wood’ remaining on either side, which may
damage the saw unit if the cuts are not parallel (3). If the
tree begins to fall, you can prevent the cutting unit from
returning by over-cutting the back cut with the front cut.
In order to ensure the cuts are parallel, you may need to
align the felling head to compensate.
2
1
TX1019722
—UN—09JAN08
3
TX1036004
—UN—04FEB08
1— Front/compression cut
2— Back/release cut
3— Barber chair
2-2-7
090621
PN=39
Summary of Contents for FL85
Page 4: ...Introduction 090621 PN 4...
Page 79: ...Index Index 3 090621 PN 79...
Page 80: ...Index Index 4 090621 PN 80...
