Stihl MS 311 Instruction Manual page 12

English
4.4 Sapwood cuts
Sapwood cuts in long-fibered softwood help pre‐
vent sapwood splintering when the tree falls.
Make cuts at both sides of the trunk at same
height as bottom of felling notch to a depth of
about 1/10 of trunk diameter. On large diameter
trees, cut to no more than width of guide bar.
Do not make sapwood cuts if wood is diseased.
4.5 Basic information on felling cut
Basic dimensions
C
The felling notch (C) determines the direction of
fall.
The hinge (D) functions like a real hinge to guide
the tree to the ground.
– Width of hinge: approx. 1/10 of the trunk diam‐
eter
– Never saw through the hinge while felling –
otherwise the tree will fall in a direction other
than the one planned – risk of accident!
– With rotten trunks, leave a wider hinge
The tree is felled with the felling cut (E).
– Cut horizontally
– 1/10 (at least 3 cm) of tree diameter higher
than bottom of felling notch (C).
The holding strap (F) or stabilizing strap (G) sup‐
ports the tree and helps prevent it from falling
prematurely.
– Width of strip: approx. 1/10 to 1/5 of the trunk
diameter
– Do not cut into the strip during the felling cut
12
C E
1/10
G
Ø
– With rotten trunks, leave a wider strip
Plunge cutting
– For relieving cuts during shortening
– For wood carving
1.
3.
2.
► Use a low kickback saw chain and proceed
with special care
1. Begin cut by applying the lower portion of the
guide bar nose – do not use upper portion
because of risk of kickback. Cut at full
strength until the depth of the kerf is twice
the width of the guide bar
2. Swing the machine slowly into the plunge
cutting position – risk of kickback and push‐
back!
3. Make the plunge cut very carefully. Risk of
pushback.
Where possible, use a plunge blade. The plunge
blade and the upper/lower side of the guide bar
are parallel.
During plunge cutting, the plunge bar helps to
keep the hinge parallel in form, i.e. the same
thickness at all points. To do this, guide the
plunge bar parallel to the sink chord.
Felling wedges
Insert the felling wedge as soon as possible, i.e.
as soon as no obstruction of saw control is to be
expected. Position the felling wedge in the felling
cut and drive in with suitable tools.
Only use aluminum or plastic wedges – do not
use steel wedges. Steel wedges can seriously
4 Working Techniques
0458-542-8221-D