Reactive Forces - Stihl MS 381 Manual De Instrucciones

Reactive Forces

The most common reactive forces are:
kickback, pushback and pull-in.
Dangers of kickback
Kickback can result in
fatal cuts.
Kickback occurs when the saw is
suddenly thrown up and back in an
uncontrolled arc towards the operator.
MS 381
Kickback occurs if, for example,
The saw chain in the area of the
–
upper quarter of the guide bar nose
unintentionally comes into contact
with wood or a solid object – e. g.,
unintentionally touches another limb
during limbing
The saw chain at the nose of the
–
guide bar is briefly pinched in the cut
QuickStop chain brake:
This device reduces the risk of injury in
certain situations – it cannot prevent
kickback. If activated, the brake stops
the saw chain within a fraction of a
second –
refer to chapter "Chain brake" in this
Instruction Manual.
Reducing the risk of kickback
Work cautiously and methodically
–
Hold the chain saw firmly with both
–
hands and maintain a secure grip
Always cut at full throttle
–
Be aware of the location of the guide
–
bar nose
Do not cut with the guide bar nose
–
Be especially careful with small,
–
tough limbs, undergrowth and
offshoots – the saw chain may
become caught in them
Never cut several limbs at once
–
Do not lean too far forward
–
Do not cut above shoulder height
–
Use extreme caution when re-
–
entering a previous cut
Do not attempt plunge cuts if you
–
are not experienced in this cutting
technique
Be alert for shifting of the log or
–
other forces that may cause the cut
to close and pinch the chain
Always cut with a correctly
–
sharpened, properly tensioned saw
chain – the depth gauge setting
must not be too large
Use low-kickback saw chains as
–
well as narrow-radius guide bars
Pull-in (A)
When the chain on the bottom of the bar
– overbucking – is suddenly pinched,
caught or encounters a foreign object in
the wood, the chain saw may suddenly
English
A
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