Chain saws are lightweight, portable, versatile power tools used for many do-it-yourself jobs around the house and yard. Clearing storm-damaged trees, pruning trees, and cutting firewood are just a few jobs where a chain saw reduces labor and increases efficiency.
The parts of a chain saw (Fig. 1) fall into two categories: the power plant and the cutting unit. Understand the parts of a chain saw before using one. There are literally hundreds of models available today, with either electric- or gasoline-powered motors and different sizes of cutting units. Cutting techniques and safety rules apply to both electric- and gasoline-powered saws. Your chain saw dealer or rental agent will be able to suggest the appropriate chain saw depending on the work you will do with it.
1.
Be Aware of Kickback
Chains saws are a versatile tool that must always be used with caution. It is absolutely essential that you read and follow all of the chain saw manufacturer's instructions and safety precautions. While no more dangerous than many other power tools, chain saws do pose the unique threat of kickback.
Kickback is the sudden upward and backward motion of the chain when the chain contacts an object at the upper tip of the guide bar (Fig. 2). The chain saw literally jumps back at you. Avoid kickback by not letting the end of the chain saw blade hit branches, stubs, stumps, or any object other than the one you are cutting (Fig. 3). Kickback can also be caused by the guide bar being caught and pinched in a log (Fig. 4). Your chain saw should have an anti-kickback chain; if your saw does not, spend the extra money to get one. Anti-kickback tips can be installed to cover the blade nose. Kickback can be avoided if you use the saw properly.
2.
Safety Guidelines
Always wear eye and ear protection. The best type is a hard hat with a full-face shield and integrated earmuffs. Wear clothing appropriate for the weather, but avoid loose-fitting clothes that may get caught in the chain or air intake of the saw. Wear heavy leather or cut-resistant gloves and boots with steel-toe reinforcements. If you do a lot of cutting, invest in metal-fiber chain saw chaps to protect your legs.
Always hold the saw with both hands, making sure that your thumbs are hooked around the handles and that your grip is tight. Your arm on the handle should be fully extended. By locking your elbow, your body will be better prepared for kickback if it occurs. (Fig. 5)
3.
Sawing Technique
Before beginning your project, familiarize yourself with the saw by making a few cuts on small logs. Elevate the log to be cut so that the chain does not touch the ground as it cuts through the log. For right-handed users: grasp the front handle bar firmly with the left hand so that your fingers wrap around it. Encircle your grip around the handle bar to get maximum control of the saw and reduce the chance of your hand slipping into the moving chain. Your right hand should wrap around the throttle control handle in such a way as to provide good saw balance. (Reverse this process for left-handed users.) Always keep both hands on the saw. Controlling the saw in this manner will help prevent kickback. Never shift hand position or cross arms to ease strain or for a better reach. If your arms tire, stop the saw and rest for a while.
Hold the saw so that the chain is not in line with your body. If you are right-handed, make cuts slightly to the right of your shoulder and head. Cut with your left arm extended as straight as possible. If your are left-handed, cut slightly to your left shoulder and keep your right arm straight. Since you will be exerting downward pressure to cut, prepare for a loss of balance by being ready to support the saw as it cuts completely through the wood.
To actually make the cut, proceed as follows:
1) With the engine idling, bring the cutting unit up above the log, with the nose of the guide bar pointed slightly upward.
2) Slowly lower the power unit portion of the saw to just above the intended cut; the chain should not touch the wood yet. Squeeze the throttle trigger so that the engine is at top speed as the chain touches the wood. Try to cut as close to the power unit as possible. The chain saw should cut through with very little downward pressure. If you find yourself exerting force, the chain is either dull or the saw is not powerful enough for the job. (Fig. 6)
3) When nearing the end of a cut, ease up on the cutting pressure without relaxing your grip. Be prepared to release the throttle trigger the instant the chain breaks through the wood. Do not permit the saw to run at full throttle.
