valutazioni - 2, GPA: 3.5 ( )

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S The lean of the tree. The lean of a tree might not be apparent due to uneven or sloping terrain. Use a plumb or level to determine the direction of tree lean. S Weight and branches on one side. S Surrounding trees and obstacles. Look for decay and rot. If the trunk is rotted, it can snap and fall toward the operator. Check for broken or dead branches which can fall on you while cutting. Make sure there is enough room for the tree to fall. Maintain a distance of 2-1/2 tree lengths from the nearest person or other objects. Engine noise can drown out a warning call. Remove dirt, stones, loose bark, nails, staples, and wire from the tree where cuts are to be made. Plan a clear retreat path to the rear and diagonal to the line of fall. 45_ Planaclearretreatpath Direction of Fall FELLING LARGE TREES (6 inches in diameter or larger) The notch method is used to fell large trees. A notch is cut on the side of the tree in the desired direction of fall. After a felling cut is made on the opposite side of tree, the tree will tend to fall into the notch. NOTE: If the tree has large buttress roots, remove them before making the notch. If using saw to remove buttress roots, keep saw chain from contacting ground to prevent dulling of the chain. NOTCH CUT AND FELLING THE TREE S Make notch cut by cutting the top of the notch first. Cut through 1/3 of the diameter of the tree. Next complete the notch by cutting the bottom of the notch. See illustration. Once the notch is cut remove the notch of wood from the tree. Final (felling) cut here. 2 in- NotchFirstcutSecondcutchesabovecenterofnotch. Hinge SAfterremovingthewoodfromthenotch, makethefellingcutontheoppositesideofthenotch.Thisisdonebymakingacutabouttwoincheshigherthanthecenterofthenotch.Thiswillleaveenoughuncutwoodbetweenthefellingcutandthenotchtoformahinge.Thishingewillhelppreventthetreefromfallinginthewrongdirection. Hinge holds tree on stump and helps control fall cutOpening of felling Closing of notch NOTE: Before felling cut is complete, use wedges to open the cut if necessary to control the direction of fall. To avoid kickback and chain damage, use wood or plastic wedges, but never steel or iron wedges. S Be alert to signs that the tree is ready to fall: cracking sounds, widening of the felling cut, or movement in the upper branches. S As tree starts to fall, stop saw, put it down, and get away quickly on your planned retreat path. 11 S DO NOT cut down a partially fallen tree with your saw. Be extremely cautious with partially fallen trees that may be poorly supported. When a tree doesn’t fall completely, set the saw aside and pull down the tree with a cable winch, block and tackle, or tractor. CUTTING A FALLEN TREE (BUCKING) Bucking is the term used for cutting a fallen tree to the desired log size. WARNING: Do not stand on the log being cut. Any portion can roll causing loss of footing and control. Do not stand downhill of the log being cut. IMPORTANT POINTS S Cut only one log at a time. S Cut shattered wood very carefully; sharp pieces of wood could be flung toward operator. S Use a sawhorse to cut small logs. Never allow another person to hold the log while cutting and never hold the log with your leg or foot. S Do not cut in an area where logs, limbs, and roots are tangled such as in a blown down area. Drag the logs into a clear area before cutting by pulling out exposed and cleared logs first. TYPES OF CUTTING USED FOR BUCKING WARNING: If saw becomes pinched or hung in a log, don’t try to force it out. You can lose control of the saw resulting in injury and/or damage to the saw. Stop the saw, drive a wedge of plastic or wood into the cut until the saw can be removed easily. Restart the saw and carefully reenter the cut. To avoid kickback and chain damage, do not use a metal wedge. Do not attempt to restart your saw when it is pinched or hung in a log. Use a wedge to remove pinched saw Turn saw OFF and use a plastic or wooden wedge to force cut open. Overcutting begins on the top side of the log with the bottom of the saw against the log. When overcutting use light downward pressure. OvercuttingUndercutting Undercutting involves cutting on the underside of the log with top of saw against the log. When undercutting use light upward pres sure. Hold saw firmly and maintain control. The saw will tend to push back toward you. WARNING: Never turn saw upside down to undercut. The saw cannot be controlled in this position. Always make your first cut on the compression side of the log. The compression side of the log is where the pressure of the log’s weight is concentrated. First cut on compression side of log Second cut Second cut First cut on compression side of log BUCKING WITHOUT A SUPPORT S Overcut through 1/3 of the diameter of the log. S Roll the log over and finish with a second overcut. S Watch for logs with a compression side to prevent the saw from pinching. See illustrations for cutting logs with a compression side. BUCKING USING A LOG OR SUPPORT STAND S R...

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