Echo X52000020 instruction manual Forces You Must Control

FORCES YOU MUST CONTROL

This section explains the forces which must be controlled to avoid injury when operating either a gas or electric-powered chain saw. Always remem- ber that your best defenses are to exercise caution and use the chain saw properly, and to be prepared to react to these forces

PULL, PUSH and KICKBACK are terms for the direction a reaction takes.

PULL - When you are cutting on top of a log with the lower portion of the chain moving toward you, the chain saw will be pulled into the wood and away from you.

PUSH - Cutting on the underside of a log pushes the chain saw toward you.

PUSH and PULL forces are controlled by anticipating which reaction will happen and adjusting your position and stance to compensate.

PULL

CUTTING ON BOTTOM OF GUIDE- BAR PULLS SAW AWAY FROM YOU

PUSH

CUTTING ON TOP OF GUIDE-BAR PUSHES SAW TOWARD YOU

WOOD

FORCE

REACTION

ROTATIONAL KICKBACK - When the chain is moving downward around the

upper nose of the bar, solid contact there may drive the bar tip upward in an Rotational kickback arc toward you. This is an extremely dangerous reaction called Rotational

Kickback. When used alone in this manual, the term kickback will always refer to the rotational kickback.

Rotational kickback is predictable, preventable and controllable. If the operator is not alert to the possibility of a kickback, it may come as a complete surprise. The possibility of kickback can be greatest if the chain is not a low- or reduced kickback type, or if the bar is not a reduced-kickback type. The best defense against rotational kickback is making sure the chain does not contact anything solid at the upper nose of the bar. This can be assured by proper installation of the Kick Guard ® device.

LINEAR KICKBACK - A sudden PUSH reaction that occurs when the chain along the top rails of the bar gets pinched in a cut. This type of reaction pushes the chain saw straight back toward the operator. The Kick Guard ® device on your bar nose acts as a stop against this type of kickback by stopping the guide bar.

Chain moving downward at impact

ROTATIONAL KICKBACK

PINCH

PINCHING TOP OF GUIDE BAR CAUSES LINEAR PUSH OR KICKBACK

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