Causes And Operator Prevention Of Kickback; Kickback Safety Features; Chainsaw Names And Terms - Craftsman CMCCS620 Instruction Manual

English
chain saw for cutting plastic, masonry or non-
wood building materials. Use of the chain saw for
operations different than intended could result in a
hazardous situation.
Causes and Operator Prevention
of Kickback
Kickback may occur when the nose or tip of the guide bar
touches an object, or when the wood closes in and pinches
the saw chain in the cut.
Tip contact in some cases may cause a sudden reverse
reaction, kicking the guide bar up and back towards
the operator.
Pinching the saw chain along the top of the guide bar may
push the guide bar rapidly back towards the operator.
Either of these reactions may cause you to lose control of
the saw which could result in serious personal injury. Do not
rely exclusively upon the safety devices built into your saw.
As a chain saw user, you should take several steps to keep
your cutting jobs free from accident or injury.
Kickback is the result of tool misuse and/or incorrect
operating procedures or conditions and can be avoided by
taking proper precautions as given below:
a ) Maintain a firm grip, with thumbs and fingers
encircling the chain saw handles, with both
hands on the saw and position your body and
arm to allow you to resist kickback forces.
Kickback forces can be controlled by the
operator, if proper precautions are taken. Do not
let go of the chain saw.
b ) Do not overreach and do not cut above shoulder
height. This helps prevent unintended tip contact
and enables better control of the chain saw in
unexpected situations.
c ) Only use replacement bars and chains specified
by the manufacturer. Incorrect replacement
bars and chains may cause chain breakage and/
or kickback.
d ) Follow the manufacturer's sharpening and
maintenance instructions for the saw chain.
Decreasing the depth gauge height can lead to
increased kickback.

Kickback Safety Features


WARNING: The following features are included
on your saw to help reduce the hazard of kickback;
however such features will not totally eliminate this
dangerous reaction. As a chain saw user do not rely
only on safety devices. You must follow all safety
precautions, instructions, and maintenance in this
manual to help avoid kickback and other forces which
can result in serious injury.
Reduced-Kickback Guide Bar, designed with a small
•
radius tip which reduces the size of the kickback
danger zone on bar tip. A reduced - kickback guide
bar is one which has been demonstrated to significantly
reduce the number and seriousness of kickbacks when
4
tested in accordance with safety requirements for electric
chain saws.
• Low-Kickback Chain, designed with a contoured
depth gauge and guard link which deflect kickback
force and allow wood to gradually ride into the
cutter. A low-kickback chain is a chain which has met
kickback performance requirements of ANSI B175.1–2012.

Chainsaw Names and Terms

• Bucking - The process of cross cutting a felled tree or log
into lengths.
• Motor Brake - A device used to stop the saw chain when
the trigger is released.
• Chain Saw Powerhead - A chain saw without the saw
chain and guide bar.
• Drive Sprocket or Sprocket - The toothed part that
drives the saw chain.
• Felling - The process of cutting down a tree.
• Felling Back Cut - The final cut in a tree felling operation
made on the opposite side of the tree from the notching cut.
• Front Handle - The support handle located at or toward
the front of the chain saw.
• Front Hand Guard - A structural barrier between the
front handle of a chain saw and the guide bar, typically
located close to the hand position on the front handle.
• Guide Bar - A solid railed structure that supports and
guides the saw chain.
• Scabbard/Guide Bar Cover - Enclosure fitted over guide
bar to help prevent tooth contact when saw is not in use.
• Kickback - The backward or upward motion, or both
of the guide bar occurring when the saw chain near the
nose of the top area of the guide bar contacts any object
such as a log or branch, or when the wood closes in and
pinches the saw chain in the cut.
• Kickback, Pinch - The rapid pushback of the saw
which can occur when the wood closes in and pinches
the moving saw chain in the cut along the top of the
guide bar.
• Kickback, Rotational - The rapid upward and backward
motion of the saw which can occur when the moving saw
chain near the upper portion of the tip of the guide bar
contacts an object, such as a log or branch.
• Limbing - Removing the branches from a fallen tree.
• Low-Kickback Chain - A chain that complies with the
kickback performance requirements of ANSI B175.1–2012
(when tested on a representative sample of chain saws.)
• Normal Cutting Position - Those positions assumed in
performing the bucking and felling cuts.
• Notching Undercut - A notch cut in a tree that directs
the tree's fall.
• Rear Handle - The support handle located at or toward
the rear of the saw.
• Reduced Kickback Guide Bar - A guide bar which has
been demonstrated to reduce kickback significantly.
• Replacement Saw Chain - A chain that complies with
kickback performance requirements of ANSI B175.1–2012
when tested with specific chain saws. It may not meet