Évaluations - 3, GPA: 4.3 ( )

Fabricant : John Deere Taille : 3.4 mb Nom Fichier : Langue d'enseignement:

These things influence the direction in which the tree will fall. Do not try to fell a tree along a line different from its natural line of fall. A B B 3. Cut a notch (C) about 1/3 the diameter of the trunk in the sideof the tree. Make the cuts of the notch so they intersect at aright angle to the line of fall. This notch should be cleaned outto leave a straight line. To keep the weight of the wood off thesaw, always make the lower cut of the notch before the upper cut. 4. The backcut is always made level and horizontal, and at aminimum of 2 inches (5 cm) above the horizontal cut of thenotch (D). 5. Never cut through to the notch. Always leave a band of woodbetween the notch and back cut (approximately 2 inches (5cm) or 1/10 the diameter of the tree). This is called "hinge" (E) or “hingewood.” It controls the fall of the tree and preventsslipping or twisting or shoot-back of the tree off the stump. 6. On large diameter trees, stop the back cut (F) before it is deepenough for the tree to either fall or settle back on the stump. Then insert soft wooden or plastic wedges (G) into the cut sothey do not touch the chain. The wedges can be driven in, littleby little, to help jack the tree over. NOTE: When bucking or felling with a wedge, it may be necessaryto remove the Safe-T-Tip® anti-kickback device to allowthe bar to be drawn through the cut. After the cut is complete, the tip should be replaced immediately. 7. As tree starts to fall, stop the engine and put saw downimmediately. Retreat along cleared path, but watch the actionin case something falls your way. C E F G 2" (5 cm) 2" (5 cm) or 1/10 DIA WARNING Never cut through to the notch when making a backcut. The hinge controls the fall of the tree, this is the section ofwood between the notch and backcut. D E 16 English OPERATION Buttress Roots A buttress root is a large root extending from the trunk of the treeabove ground. Large buttress roots should be removed prior tofelling. Make the vertical cut (A) into the buttress first, followedby the horizontal cut (B). Remove the resulting loose section (C) from the work area. Utilize the proper instructions from theOperation-Tree Felling section of the manual after the largebuttress roots have been removed. A C B Bucking Bucking is the term used for cutting a fallen tree to the desiredlog length. • Cut only one log at a time. • Support small logs on a saw horse or another log whilebucking. • Keep a clear cutting area. Make sure that no objects cancontact the guide bar nose and chain during cutting, this cancause kickback (D). To avoid the danger, keep the Safe-T- Tip® anti-kickback device attached while cutting. D • During bucking operations always stand on the uphill side sothat the cut-off section of the log can not roll over you. • Sometimes it is impossible to avoid pinching (with just standard cutting techniques) or difficult to predict which way a logwill settle when cut. To avoid pinching while cutting, review thefollowing sections, Bucking with a Wedge and Logs UnderStress. Bucking with a Wedge If the wood diameter is large enough for you to insert a softbucking wedge (E) without touching the chain, you should use thewedge to hold the cut open to prevent pinching. E NOTE: When bucking or felling with a wedge, it may be necessary toremove the Safe-T-Tip® anti-kickback device to allow the barto be drawn through the cut. After the cut is complete, the tipshould be replaced immediately. Logs Under Stress • Make the first bucking cut (F) 1/3 of the way through the log andfinish with a 2/3 cut (G) on the opposite side. As the log is beingcut, it will tend to bend. The saw can become pinched or hungin the log if you make the first cut deeper than 1/3 of thediameter of the log. Log Supported at One End: LOAD (G) FINISHING CUT (F) 1st CUT 1/3 Dia Log Supported at Both Ends: (F) 1st CUT 1/3 Dia LOAD (G) FINISHING CUT Give special attention to logs under stress to prevent the bar andchain from pinching. English 17 OPERATION Types of Cutting Used Overbucking Begin on the top side of the log with the bottom of the saw againstthe log; exert light pressure downward. Underbucking Begin on the under side of the log with the top of the saw againstthe log; exert light pressure upward. During underbucking, thesaw will tend to push back at you. Be prepared for this reactionand hold the saw firmly to maintain control. B WARNING Springpoles are dangerous and could strike the operator, causing the operator to lose control of the chain saw. This could result in severe or fatal injury to theoperator. • When pruning trees it is important not to make the flush cutnext to the main limb or trunk until you have cut off the limbfurther out to reduce the weight. This prevents stripping thebark from the main member. Underbuck the branch 1/3through for your first cut, your second cut should overbuck todrop the branch off. Now make your finishing cut smoothly andneatly against the main member so the bark will grow back toseal the wound. Fin...

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